Hurricanes, High-rises, and Hubris

[Margie Kieper]

This started out as an observation, but turned into a very interesting exercise on its own.

This is a summary of information from the web, best track data, recon data, and a 1994 engineering report on Hugo. The 1994 report, which I’ll quote extensively in this time sequence of wind events, was directed specifically at assessing surface windspeeds from Hugo and relating the winds to a damage assessment. Here they cited their sources of data:

“Radar images recorded on film by the WSFO in San Juan were particularly valuable in establishing wind directions and the presence of intense rainbands during the passage of Hugo. WSFO radar began tracking Hugo southeast of St. Croix early on September 18 and provided essentially continuous tracking until Hugo passed out of range late in the day. Also of value in assessing the relative strength of Hugo and, hence, the intensity of surface winds, were estimates of central pressure and eye diameter presented in post-storm summaries prepared by the NHC (Lawrence, 1989). Other sources of information were the flight-level records obtained by NOAA and USAF reconnaissance aircraft, satellite data, wind damage observations, and reports by residents of the affected areas.

“In the following paragraphs is an assessment of surface-wind speeds for each of the major areas affected by Hugo. Also included is a description of the reported speeds and the final disposition of these reports. To be consistent with standard wind-speed measurement and reporting procedures, the speeds described in the following sections refer either to peak gusts or sustained speeds at a height of 10 m in flat, open terrain, typical of airport exposures. It is important to note that wind speeds measured under nonstandard conditions may differ widely from standard measurements.

“In order to gain some perspective of the severity of the estimated and measured surface winds, comparisons are made with design wind speeds specified by local and regional building codes in the Caribbean. Finally, the extraordinarily high surface-wind speeds reported for St. Croix and St. Thomas are cast in terms of mean recurrence intervals (MRIs) derived from a recent study of wind statistics for the Caribbean region.â€￾

This summary statement identifies the maximum sustained windspeeds determined by the report:

"Observed damage in the areas affected by Hurricane Hugo is in general agreement with the surface-wind speeds listed [below]. This damage ranged from superficial to total devastation. In general, the most damaging winds were located in the northeast quadrant of the storm. This quadrant was also where the most intense rainbands, as indicated by their radar reflectivity, were located."

Probable Maximum Wind Speeds

Location................Max Sust Wind (kt)..Gust (kt)
---------------------- ------------------ ------------
Virgin Islands:

St. Croix...............110.................135.............(Cat 3)
St. Thomas...............85.................105.............(Cat 2)

Puerto Rico:

Culebra.................105.................130.............(Cat 3)
Vieques..................95.................115.............(strong Cat 2)
Roosevelt Roads..........85.*..(90).........104.*..(110)....(Cat 2)
San Juan Int’l Airport...67.*..(72)..........80.*...(86).....(Cat 1)

* Denotes actual measurement, unadjusted for height; adjusted measurement following in parentheses [added by me for clarity]

The report found the damage consistent with these windspeeds.

Note that this does not contradict the best track. The best track identifies the maximum sustained winds that are located somewhere in the storm and not necessarily sampled. This report, which carefully reviewed the damage in relation to the wind direction and thus the application quadrant of the storm, observed that the most damaging winds, i.e, the strongest winds, were in the northeast quadrant. The wind readings on mainland Puerto Rico, which were from the weaker western side of the storm, support that as well.

In conclusion, there is no evidence of sustained Cat 3 winds on the Puerto Rican mainland, either from direct ground measurements or recon data or by a very thorough post-analysis. In order to claim otherwise you would have to be rejecting, wholesale, all the ground measurements, recon obs, radar obs from San Juan, and a detailed engineering assessment of wind damage. That is not logical.

There is a suggestion that sustained winds slightly higher than 90 kt could have occured at Luquillo. Slightly could be bent to go so far as 96 kt, although that would be pushing it. Nevertheless, let's suppose that to be a reasonable, although unlikely possibility. That just puts you at the absolute threshold of Cat 3 sustained winds. There is no way that sustained Cat 4 winds can be construed from such a situation.

Your video was a good video, without the hyperbole. Why do the winds you videotaped at Luquillo "have to be" Cat 4 sustained winds when it is simply not a possibility?

- - - - - - -

[part 2 and part 3 in subsequent posts -- I hit the size limit]

 

[Margie Kieper]

- - - - - - -

I’m going to provide the various detailed information on location and wind speeds in chronological order. Notice how, as time goes on, pressure readings consistently rise and wind speeds fall. Hopefully this will clarify the intensity of winds around the time of the video at Luquillo. If not, there is no other detailed information I have access to at this time to provide. And I think I would be too worn out to write any more on this topic!

Time sequence on the 17th and 18th (UTC, which is AST/EDT+4):

On the afternoon of the 17th recon starts to observe concentric eyewalls.

A composite recon wind plot from late on the 17th, 2251Z (which would include values from a few hours earlier), shows 135 kt winds in the eyewall on the east and north legs; the northern leg is positioned in the right front quad of the NW-moving Hugo. Hugo is strengthening. This is seven hours before the center landfalls on St. Croix, although eyewall winds will start to effect them by around 0415Z.

0000Z Best track records document Hugo has intensified to 130 kt just prior to approaching St. Croix.

0000Z best track:
center position 17.2N 64.1W, about 50 nmi ESE of St. Croix
pressure 934 mbar
intensity 130 kt

A recon vortex fix at 0312Z at 17.43 -64.50, or about 20 nmi SE of St. Croix, measures a pressure of 935 mbar, a circular closed eyewall 18 nmi in diameter, but noted the max flight-level wind was measured much earlier, 113 kt at 2320 in the south quad.

A recon vortex fix at 0526Z at 17.58 -64.73, or about five miles south of St. Croix, measures a pressure of 939 mbar, an elliptical eyewall stretching 25 nmi by 15 nmi east to west, opening to the SE, and a max flight level wind of 125 kt in the east quad at 0518Z (at the borderline between Cat 3 / Cat 4 intensity).

Best track records starting with 06Z note that Hugo has begun to weaken.

- - - - - - -

St. Croix:

0600Z best track:
center position 17.7N 64.8W, just onshore St. Croix
pressure 940 mbar mbar
intensity 120 kt

from about 0700Z to 0900Z, eye executes a trochoidal loop keeping St. Croix in the strong northeastern eyewall for several hours.

“Wind damage on St. Croix was strikingly similar to that observed at Darwin, Australia, following Cyclone Tracy (Marshall, 1976). For the Darwin subdivisions experiencing the heaviest damage, the peak gusts averaged 135 knots (155 mph), and it is considered likely that the peak gusts on St. Croix were of similar magnitude. Analyses of numerous stripchart records from Hugo in South Carolina and from previous Atlantic and Gulf Coast hurricanes indicate that the ratio of peak gust to corresponding sustained speed is in the range 1.20 to 1.25. Therefore, if 135 knots is representative of the maximum gusts, the corresponding maximum sustained wind speed on St. Croix would be approximately 110 knots (127 mph). Because of the accelerating effect of the terrain on surface winds near Christiansted, wind speeds based on observed local damage would tend to be overestimated.

“An independent estimate of surface-wind speeds can be obtained from data collected by reconnaissance aircraft at the 700 mb level. These data indicate maximum speeds of about 130 knots (150 mph) during Hugo's passage over St. Croix (Lawrence, 1989). Data presented by Powell and Black (1989) suggest that the ratio of the 10-min mean speeds at 10 m over rough water to the 700 mb flight-level speeds is approximately 0.7, which in this case yields a 10-min mean speed of 90 knots (104 mph). Again, from the analyses of stripchart records mentioned above, the ratio of the maximum sustained speed to the corresponding 10-min mean speed in flat, open terrain is approximately 1.2. Thus, the corresponding sustained speed for standard exposure conditions is about 110 knots (127 mph).”

The report concluded the maximum sustained winds at St. Croix were 110 kt (strong Cat 3 intensity).

- - - - - - -

Vieques, Puerto Rico:

1130Z center passes the very eastern tip of Vieques.

“The highest measured wind speeds on Vieques were gusts of 85 knots (98 mph) recorded at the U.S. Navy's Isabel Segunda facility by the 9-m anemometer mast just prior to its failure at approximately 0900 GMT. Comparisons of damage on Vieques with damage at Roosevelt Roads Naval Station, where a verifiable wind-speed record was obtained, suggest peak gusts of approximately 115 knots (132 mph) and corresponding sustained speeds of 95 knots (109 mph).”

The report concluded the maximum sustained winds at Vieques were 95 kt (strong Cat 2 intensity).

- - - - - - -

Culebra:

“It was during the last few hours of Hugo's approach to Puerto Rico that Culebra probably experienced the worst wind effects…An unofficial estimate of winds gusting to 150 knots (173 mph) in the harbor at Culebra was made by a mariner who rode out the storm on his sailboat and videotaped his anemometer.”

“Strong winds from the northeast began to affect Culebra at about 0900 GMT when Hugo was located approximately 75 km to the south-southeast. Data from San Juan radar indicate that intense rainbands began to move over Culebra from the northeast at 1020 GMT. The wind direction changed from northeast to east as the eye began to engulf Culebra at about 1130 GMT. At this time the circulation, as indicated by the radar reflectivity of the rainbands, became less well defined, making it difficult to establish accurately the position and diameter of the eye. In fact, one eyewitness at Ensenada Honda on the south side of Culebra claimed that no lull was observed during the passage of Hugo. This same source reported a peak gust of 140 knots (161 mph) at 1130 GMT. The anemometer in this case was mounted on the mast of a boat that had been driven aground in Ensenada Honda approximately 1/2 hour earlier.

“The central pressure continued to rise as Hugo moved past Culebra, reaching 956 mb at 1300 GMT. Based on the observed damage, the storm track relative to the island, and the steady weakening of Hugo after it passed St. Croix, it is estimated that peak gusts of 130 knots (150 mph) and maximum sustained speeds of 105 knots (121 mph) for standard exposure conditions were experienced on Culebra”

The report concluded that the maximum sustained winds were 105 kt (Cat 3 intensity), from the stronger eastern side of the storm, and discounted the claims of gusts higher than 130 kt (150 mph). Note in the subsequent section that this is the same timeframe (1130Z) when the western eyewall is affecting mainland Puerto Rico, with much weaker sustained winds.

[part 3 in next post]

 

[Margie Kieper]

- - - - - - -

Puerto Rican mainland:

“Satellite data and San Juan radar indicate that the west wall of the eye moved over land near the towns of Ceiba (Roosevelt Roads Naval Air Station), Fajardo, and Luquillo, while the east side of the eye remained over water.”

“…the anemometer site at Roosevelt Roads Naval Station is well exposed, and height of the propeller/vane anemometer is 7 m. The time history of recorded peak gusts, unadjusted for anemometer height [below], shows that peak gusts of 104 knots (120 mph) occurred between 1150 and 1220 GMT…and an almost complete penetration of the eyewall was observed at 1250 GMT.”

“…The 7-m anemometer at Roosevelt Roads is located adjacent to the main runway and has a clear exposure to wind from all directions.”

“Maximum sustained winds at this site were approximately 85 knots (98 mph). Mechanical equipment and a part of the air operations building roof were lost at 1339 GMT, terminating wind-speed and direction recordings at Roosevelt Roads. Because the site satisfies the requirements for standard exposure, the only required adjustment to the data is for the height of the anemometer. This would have the effect of increasing the observed speeds by about 6 percent.”

The report concluded that the maximum sustained winds at Roosevelt Roads were lower (85 kt) from a complete review of the stripchart data, but also concluded that adjusting for the anemometer height resulted in maximum sustained winds of 90 kt, matching the NHC value (Category 2 intensity).

This same western eyewall (actually, the northwestern eyewall given the eliptical slant of the eyewall at this time), subsequently passes over Luquillo and just to the east of San Juan.

- - - - - - -

1200Z best track:

center position 18.2N 65.5W , about halfway between Vieques
and SE tip of mainland Puerto Rico
pressure 945 mbar mbar
intensity 110 kt

At 1208Z, a recon vortex fix in the center of Hugo’s eye, located at 18.3 -65.5, or about 6 nmi to the east of Fajardo, measures a pressure that has risen to 955 mbar, and observes the eye is approximately elliptical, stretching 30 miles along an axis of 60 degrees (that is, an axis stretching from WSW to ENE), and 20 miles wide along the perpendicular axis. Also noted is that the eye is open to the SE. These are all signs of weakening and of the in-progress ERC. The recon also notes that the highest flight level winds encountered on the leg leading up to the center fix, which traveled into the eye from the south, were winds from the west at 67 kt (i.e, zippo).

“A storm chaser was able to position himself in a multistory condominium in Luquillo and produced a remarkable videotape of the approach and passage of Hugo's eye directly over head. The videotape documents damaging wind and rain effects on nearby structures during major rainband and eyewall passages in Hugo, as well as the chaotic state of the adjacent sea surface. He used a digital barometer to measure a lowest pressure (956 mb). San Juan, which remained outside the eye, recorded a minimum pressure of 970.3 mb. The radar sequence supports the pressure data indications that Hugo was filling as it crossed the northeast coast of Puerto Rico. However, it must be emphasized that the western eyewall passed just to the east of metropolitan San Juan, probably affecting Loiza and Pinones; moreover, this geometry is entirely consistent with the large gradations of damage and surge effects (especially overwash) documented by the team from Catano eastward.”

At 1238Z the same recon flight on its way north records the highest flight-level wind speed in the stronger northern eyewall: 108 kt. This translates to surface-level winds of 92 kt (using 85% reduction) – strong Cat 2 winds. This could also be considered the northwestern eyewall given the elliptical shape of the eyewall recorded minutes earlier. This maximum is located about 25 nmi to the NNE of Luquillo at this time.

At 1230Z, San Juan radar shows that Hugo's eye has partially filled.

1300Z fix: 18.30 -65.60 just offshore, 3 nmi SE of Fajardo

1330Z center passes just to the east of the northeast tip of Puerto Rico. San Juan radar shows that Hugo's eye has completely filled.

Highest winds at San Juan:

The record of sustained winds from San Juan airport indicates the close passage of the western eyewall as occurring between 1330Z and 1400Z; these highest sustained speeds of 65-67 kt are at the threshold for Cat 1 sustained winds:

1989 9 18 13 2 340 27.8
1989 9 18 13 20 350 26.8
1989 9 18 13 25 350 27.8
1989 9 18 13 32 350 28.8
1989 9 18 13 37 340 33.4
1989 9 18 13 45 350 34.0
1989 9 18 13 50 340 34.5
1989 9 18 14 15 320 29.3
1989 9 18 14 50 280 23.7

The highest gusts during this same timeframe are on the order of 80 kt, consistent with a ratio of 1.20 to 1.25:

1989 9 18 13 25 350 34.5
1989 9 18 13 32 350 39.6
1989 9 18 13 41 340 39.6
1989 9 18 13 46 350 40.1
1989 9 18 13 52 340 41.2
1989 9 18 14 15 320 41.2
1989 9 18 14 44 280 35.5

“The WSFO at San Juan recorded peak gusts of 80 knots (92 mph) between 1350 and 1415 GMT, and the maximum sustained wind speed was 67 knots (77 mph). Adjustment for the 6.1-m height of the F420 C anemometer would increase the plotted wind speed in by about 7 percent.”

And from a separate section on surface wind speeds:

“The WSFO at Luis Munoz Marin International Airport in San Juan recorded peak gusts of 80 knots (92 mph) between 1350 and 1415 GMT..The maximum sustained wind speed was 67 knots (77 mph). Adjusting this figure to take into account the 6.1-m height of the F420C anemometer would increase the maximum sustained wind speed by about 7 percent to 72 knots (83 mph).

“It is known from eyewitness accounts that the eye passed over the region from Luquillo east to Cape San Juan. Because the winds there would have been directly off the ocean, speeds slightly higher than those at Roosevelt Roads Naval Station may have been reached.”

The report concluded that maximum sustained winds at San Juan’s airport, which was just on the fringes of the western eyewall, were 72 kt (Category 1), and that maximum sustained winds at Luquillo may have been slightly higher than at Roosevelt Roads; that is, slightly higher than 90 kt.

Since the range of Cat 2 winds is 83-95 kt, only by an overly generous allowance beyond "slightly" would Luquillo have received sustained Cat 3 winds, but more likely received Cat 2 sustained winds and Cat 3 gusts, given the standard ratio for over water of 1.20 to 1.25, with gusts probably no higher than 115 kt.

- - - - - - -

“Hugo's ill-defined eye moved north-northwest after hitting the northeast coast of Puerto Rico, and by noon on September 19 [sic; it was actually noon on the 18th] was over open water north of San Juan with maximum sustained winds of 109 knots (125 mph) and minimum sea-level central pressure (MSLP) of 957 mb.”

1400Z fix: 18.46 -65.76 offshore, 7 nmi NNW of Luquillo

At 1428Z another vortex fix at 18.55 -65.87, or about 5 nmi north of the Puerto Rico coast about halfway between San Juan and Luquillo, shows similar mslp as the earlier vortex, slightly higher, 957 mbar, and expansion of the elliptical eyewall to 40 and 30 nmi diamters, respectively, along an axis of 30 degrees (SSW to NNE), and indicates the eye is open to the south. It has found no stronger flight-level winds than 65 kt, and the previously measured 100 to 110 kt at 1235Z on the earlier fix.

1500Z fix: 18.62 -65.92 offshore, 11 nmi NNE of San Juan

1800Z best track:
center position 19.1N 66.4W, about 45 nmi north of central Puerto Rico
pressure 958 mbar mbar
intensity 105 kt

“The storm's radar structure, as documented by the 5-cm belly radar from the NOAA WP3D aircraft, is [below]. Note that the southeastern half of the storm is nearly devoid of rainbands.”

“a P-3 radar image from around 20Z on the 18th shows a much deteriorated eyewall structure with no rainbands remaining over the southeastern two thirds, and the remaining strong convection to the right of the forward movement” [from about 350 to 015 degrees]

- - - - - - -

I am about to become very busy and this will likely be my last post for awhile...unless an amazing TC comes along that cannot go without notice.

 

[Jim Leonard]

I will continue stand by my estimate of wind gusts of over 140kts in Luquillo P.R. during Hugo, Case Closed!!!! If you would read the report the damage survey indicated F-3 damage in St Croix and N/E Puerto Rico. Unless you were there you cannot dispute it. I have experienced over 50 hurricanes of all sizes and intensities except a category-5. The video on a 2 inch muddy screen does not tell the real story of the force of the wind, you have to be there. There was an exploding house that Mike and I caught on tape along with flying debris of all sizes and constant sound of glass breaking from all directions. Palm trees were reduced to stix. All windows in the condo facing the ocean were blown in to a point that the metal front doors to some apartments were blown out into the hallway. Windows on the lee side were blasted out frames and all. I have been in many hurricanes with 110mph winds and the damage is much lighter than in Puerto Rico. Mike has shown a still of a concrete two story house in front of our location with the second floor blown off.
Wind gust of 164mph was recorded at TPC during hurricane Andrew outside of the eyewall. Even though this was on top of a ten story bluilding the wind at tree top level was probably around 150mph. The tree damage in that area was nothing like the tree damage in N/E Puerto Rico.
This report of a gust to 120mph at Roosevelt Roads was on the southside of a decaying southern eyewall down wind of a Mountain range in eastern P.R.

 

[Michael Laca]

Hi Margie - In an attempt at brevity, I am only responding to the most relevant points from your post...

“...Also of value in assessing the relative strength of Hugo and, hence, the intensity of surface winds, were estimates of central pressure and eye diameter presented in post-storm summaries prepared by the NHC (Lawrence, 1989)."

I have no challenge to this overall citation, other than "estimates of central pressure" in "summaries prepared by the NHC" is skewed with respect to the observed pressure at Luquillo...which was likely lower than documented.

“In the following paragraphs is an assessment of surface-wind speeds for each of the major areas affected by Hugo. Also included is a description of the reported speeds and the final disposition of these reports."

Again, no challenge. I am happy to stand firmly in contradiction to this particular report's final disposition on several points. And I have previously made numerous citations to the 1990 survey, which also stands in contrast to numerous conclusions from this report.

"In general, the most damaging winds were located in the northeast quadrant of the storm. This quadrant was also where the most intense rainbands, as indicated by their radar reflectivity, were located."

I am in agreement that the highest flight-level winds were located in the northeast quadrant. That said, the following portion of the report's statement -- "This quadrant was also where the most intense rainbands, as indicated by their radar reflectivity, were located" -- is absolutely not true for numerous instances during Hugo's lifecycle and particularly between the time it left St.Croix and when it crossed Puerto Rico. Even in the 17/23Z airborne radar image that you posted, there is a narrow strip of intense eyewall convection in the NE quadrant, but the most intense reflectivity in the eyewall is from the north through west quadrants, with the thickest portion of the eyewall squarely in the NW quadrant. The 700mb winds superimposed on that radar image, do indeed indicate a peak flight-level wind of 140kts due east of the center, in an area of practically no intense reflectivity...with another maxima of 135kts due north of the center right in the intense convection. My comments relating to this particular image: 1. The recon flight plan did not allow for sampling the winds over the NW eyewall, where the most intense reflectivity is located. 2. While it is likely that the flight-level winds in the NW eyewall probably were not as strong as those shown in the NE quadrant (140kts), I would firmly suspect that they DID mirror the values in the Northern eyewall (135kts)...and, because this is where the most intense convection is, more of the flight-level winds would have been brought down to the surface...probably yielding higher surface winds, especially in gusts, in this area... probably even higher than what was occuring over the Eastern eyewall, where flight-level winds were slightly stronger, but there was no appreciable convection

Probable Maximum Wind Speeds
Location................Max Sust Wind (kt)..Gust (kt)
---------------------- ------------------ ------------
Virgin Islands:
St. Croix...............110.................135....... ......(Cat 3)
St. Thomas...............85.................105....... ......(Cat 2)

Puerto Rico:
Culebra.................105.................130... ..........(Cat 3)
Vieques..................95.................115... ..........(strong Cat 2)
Roosevelt Roads..........85.*..(90).........104.*..(110).... (Cat 2)
San Juan Int’l Airport...67.*..(72)..........80.*...(86).....(Cat 1)

I strongly disagree with virtually every one of the windspeed estimates shown in the the referenced table...both sustained and gusts. Even with actual observation at Roosevelt Roads, where I agree with the observed value accurately representing the windspeeds in the Ceiba/Roosevelt Roads NAS area, I do not agree with the report's assessment that the observation platform sufficiently represents a "standard exposure" or that the anemometer is "well exposed". It is... in terms of it's immediate surroundings... but, particularly in light of the direction of Hugo's strongest winds in this area (over land from NNW to NW) and with a 3,500ft elevation only 5 miles distant...and in the direction that the strongest winds would be coming from... I am quite confident that surface winds in the area of Ceiba and Roosevelt Roads were reduced, wholesale, by around 15-17%... from what they would have been from an onshore, non-blocked vantage point in the western eyewall.

From my perspective the Roosevelt Roads values listed in this table cannot be used, without additional adjustment, to accurately reflect valid windspeeds in other areas affected by the eyewall over NE Puerto Rico. Additionally, as far as the remaining estimates...they are just that, estimates. And, owing to the primary methodology for determining surface winds in this this report, (i.e. applying a standard reduction to observed flight level winds), in my opinion are overly, if not excessively, conservative...likely by 10-20kts.

The report found the damage consistent with these windspeeds.

The report actually states, "Observed damage in the areas affected by Hurricane Hugo is in general agreement with the surface-wind speeds listed." There is a lot of generalization in that "general agreement" comment. And, again, if the game is to simply cite the perspective of an independant damage survey, the 1990 DOC-NOAA damage assesment yielded upper F1-F2 damage, with localized areas of possible F3 damage (attributable to microbursts or other orographic effects) with peak winds estimated at 161mph across the most severely impacted areas, including: St.Croix, Vieques, Culebra, Fajardo and Luquillo.

In conclusion, there is no evidence of sustained Cat 3 winds on the Puerto Rican mainland, either from direct ground measurements or recon data or by a very thorough post-analysis. In order to claim otherwise you would have to be rejecting, wholesale, all the ground measurements, recon obs, radar obs from San Juan, and a detailed engineering assessment of wind damage. That is not logical.

Really? No evidence to whom? My own personal observations, as well as those of four other very experienced chasers, along with 25 years of field interceptions affords me a very unique perspective on Hugo's impacts to Puerto Rico. I am certainly not rejecting... all the ground measurements (all two of them...both compromised in some way); the recon obs (which did not consistently sample the NW eyewall); radar obs from San Juan (which do show that the highest reflectivity frequently WAS in the NW quadrant); or a detailed engineering assessment of wind damage (which is no more or less credible than the damage assesment from the 1990 survey, which had different findings).

I would challenge that if there is any "wholesale rejection" of data, it is your disregard for the 1990 survey findings and, more importantly, the qualified first-hand experience and testimony of myself and four other chasers, who actually were there. Furthermore, what is "not logical" is to assume that the data in ANY of these reports is completely static and cannot be argued and/or revised. If that were the case, there would be no need for the HRD forensic re-analysis effort that has been going on for years and has made hundreds, if not thousands, of changes to prior best-track positions and intensities.

<<continued>>

 

[Michael Laca]

<<continued>>

There is a suggestion that sustained winds slightly higher than 90 kt could have occured at Luquillo. Slightly could be bent to go so far as 96 kt, although that would be pushing it. Nevertheless, let's suppose that to be a reasonable, although unlikely possibility. That just puts you at the absolute threshold of Cat 3 sustained winds. There is no way that sustained Cat 4 winds can be construed from such a situation.

Wow... sustained winds of 96kts in Luquillo, I guess I should thank you for your generosity in allowing for that much? Even if we do suppose your "reasonable, although unlikely" 96kt value is valid, it is based on a derivation from the already flawed perspective of the (85)90kt record at Roosevelt Roads. I am curious, assuming again that we put aside the small fact that I actually witnessed it first-hand, and that your expert opinion on Hugo's intensity in Luquillo (from snowbound Minnesota) is true... what is your perspective and wind estimates for the numerous other recent videos showing high winds events.

What would you estimate the sustained/peak winds in this video from Mike Theiss, during the eyewall of Hurricane Charley in Charlotte Harbor?http://www.ultimatechase.com/Video_Library/Hurricanes/Hurricane_Charley_Gas_Station_Stream.htm

What about this clip from Jim Edds, also during Charley in Punta Gorda?http://www.extremestorms.com/charley.wmv

What about my video from Belle Meade in Hurricane Wilma?
http://www.tropmet.com/images/gallery video/mpeg/Hurricane_Wilma_3_320_512kbs.wmv

...or my video from Key West during Hurricane Rita?
http://www.tropmet.com/images/gallery video/mpeg/Hurricane_Rita_7_320_512kbps.wmv

I really am curious and would like to hear your personal estimates of sustained and peak winds in each instance.

Your video was a good video, without the hyperbole. Why do the winds you videotaped at Luquillo "have to be" Cat 4 sustained winds when it is simply not a possibility?

Thank you for the compliment on the video. The short answer to your question is, because it is the truth. What I infer from your comment "[My] video was a good video...why do the winds..'have to be' Cat 4"...is that you appear to believe I am either interested in somehow inflating the appeal of the video, or that my pride as a storm-chaser would be somehow bruised. Neither could be farther from the truth and if you think otherwise, then you have missed the point entirely. I'll also remind you that you are the one who started this debate...and accused me, rather publicly, of hubris! I am just responding to what ultimately are your personal perspectives and citations from other people's work and documents, as they relate to my video. Now...just as you have asked me, I also ask, why is it so important for you to discredit my estimates of what I personally experienced and videotaped in Luquillo?

Your comment that category four winds at Luquillo are "...simply not a possibility", just reiterates that you are not willing to accept anything other than what is "officially" documented, and even then only what fits your argument. I am fully willing to respect the perspectives of ALL of these documents and also accept that you personally do not believe that category four conditions impacted Luquillo. But, to assert that there isn't even a "possibility" is tantamount to saying that I don't know what I'm talking about; that I haven't spent the last 18 years evaluating and re-evaluating my own (as well as others) footage from Hugo to refine my estimates; and that I have basically overestimated wind speeds by 20kts, or more, for every storm I have intercepted over the last two and a half decades.

Even though you claim to have approached the subject of this debate from an "open-minded" and evaluative perspective, you have been more than willing to discount my personal observations and estimates, and those of other experienced chasers, who were actually in Hugo...presumably for lack of empirical data. That said, you were more than ready, in your original post, to provide your own expert analysis and wind estimates... 18 years later, watching a highly-compressed and pixelated video on YouTube.

 

[Margie Kieper]

Hi all -- just a quick update that I received feedback from Dr. Golden, regards asking him about the ambiguity in the 1990 Hugo report, and whether or not it was superseded by the 1994 report. He replied, "I stand by my report for the NAS/NRC team in 1994; you should use our report and the NHC post-season report." And these were the sources for information contained in my last posts (along with recon data and NOAA IR imagery), as I assumed the more-in-depth 1994 report superseded the earlier one.

Michael has explained to me that he believes he experienced 115 kt winds at Luquillo, not 90 kt, and does disagree with the results of the 1994 NAS/NRC report and the NHC post-season report on Hugo mentioned above. In turn, I let Michael know that if he had had a statement with the You Tube video description stating that his conclusions were different from the official assessments, I would not have had an issue with the description of the video.

- - - - - - -

This continues to be an interesting topic, as the damage issue ties to a recent talk from the 2006 AMS conference (on Hurricanes and Tropical Meteorology) on collapsing precipitation cores in open-eyewall hurricanes such as Hugo. An extended abstract is provided as well that graphically illustrates the process using radar imagery from Ivan at landfall in Baldwin County, AL. I found this facinating...as if the eyewall's ongoing effort to rebuild constituted a last hurrah. These collapsing cores can produce extreme wind damage. The 1994 report on Hugo documented a string of microburst damage associated with the eyewall passage along the path towards Puerto Rico, including severe damage on the islands of St. Croix and Vieques. The report concluded that the worst damage was, in fact, due to microbursts, and not simply sustained winds.

This may also be of interest -- there is a personal account on WeatherMatrix, I believe, from someone who lived in Puerto Rico and experienced a lot of tree damage on their property due to microbursts associated with Hugo. Sorry I don't have the link.

 

[Jim Leonard]

Michael.
It is quite obvious to me that this person will go to great lengths to discredit your Hugo report. She has even had to contact Joe Golden to try disputing what all of us witnessed. You have taken the time and energy to explain in every detail of what occurred that day. This discussion in my estimation will go on forever because this person will never be convinced that the winds in Luquillo Puerto Rico were more than 90kts.

 

[Jose Garcia]

Hello to all...

This is my first post on this forum and I've been reading very closely this debate about the intensity of hurricane Hugo when it hit Puerto Rico. First, I experienced hurricane Hugo in the town of Gurabo which is about 20 miles south of San Juan in an interior valley which is mostly open to the sea towards the east. Hurricane Hugo was my very first hurricane experience and also for people like my parents and it was a very impressive experience. We never got the max. winds of the storm but we were certainly at the core of hurricane intensity winds for many hours with the worst conditions being experienced at around 10am when the eye was just to our NE passing over the Luquillo- Rio Grande area. My personal estimates based on other hurricane experiences and pictures is that the Gurabo area experienced peak sustained winds or around 90-105mph with gusts probably as high as 120mph.

I remember going to the NE tip of the island after Hugo and the sight was that of a nuclear bomb attack, at least that was the impression for a kid of my age at that time. When the years passed and I started to study hurricanes more in detail (specially after the 1995 season which was very active for us in the NE Caribbean) I got more interested in re-evaluating Hugo's intensity. This was mainly because I consistently heard from weather reporters here that Hugo was a category 2 hurricane in Puerto Rico, some even said that it was a category 1 storm. That didn't sound logical to me. Specially when I read the wind reports of Roosevelt Roads and the pictures of the Naval Station after the storm didn't match to me. The wind damage there to buildings in more exposed areas and vegetation was a lot similar to that of St. Croix. Also the videos and pictures of during and after the storm in San Juan did not match with the report of 77mph winds and peak gust of 92mph. Some pictures of Parque del Indio in Condado on the Beach showed every palm tree without fronds and damage in the Hato Rey area inland in San Juan was too strong to what one would expect from a category 1 intensity hurricane. With this in mind, lets get into the debate.

Margie Kieper said:

<<My first thought on viewing the video was that the top windspeeds appeared to be around 100-110 mph (about equivalent to 90-95 kt) -- a strong Cat 2, based on the size of flying debris that was seen, and the condition of the palms after the high winds had passed (the majority were not denuded). I also observed the winds were mainly being filmed as they funneled between two high-rises (Bernoulli effect).>>

The theory of a Bernoulli effect in the video is highly incorrect, I have two, two hours-long videos of hurricane Hugo (the same ones you saw much shorter in the small pixeled You Tube video) and there is only one portion of the video in which they take scenes between the two buildings and that was before they got the peak winds. There are only two condos in that area which were the Sandy Hills (unless I do not know the area enough which I highly doubt because I've been there many, many times) in which they were and the video was taken facing generally west as Richard Horodner pointed out, this was facing towards the Costa Azul area were there were no condos near as I expressed before. So, with all due respect, your Bernoulli effect argument on this video is incorrect.

<<My second thought was that someone who lives in a coastal high-rise in an area vulnerable to hurricanes was going to watch this video, read the information provided about the video, and conclude that not only would it not be necessary to evacuate any major hurricane (Cat 3-4-5) bearing down on them, since the high-rise in the video remained intact during "Cat 4" winds, but that it might be a fine and dandy thing to sit and watch it right out their window.>>

Where you expecting the condo to collapse? I mean, this has been discussed a lot in this debate and it seems extremely clear that even windows on the lee side of both Sandy Hills were ripped of the buildings not to mention the apartments facing towards the ocean, that has to give any person an idea of what would be the hazards of bearing a major hurricane in a condo.



<<As already mentioned Hugo was not a Cat 4 at landfall in Puerto Rico, but a Cat 3. Peak windspeeds were determined to be 127 mph (110 kt), but likely remained offshore. The highest sustained winds measured on land in Puerto Rico were Cat 2.>>

Have you made at least a little geographical analysis of the area of the measurement? The location of Roosevelt Roads is in Ceiba, the extreme eastern tip of Puerto Rico, it has el Yunque Montain Range to its West, it has 200-300 ft mountains to its north and a 250 ft hill to the ESE of the runway. It has the 3600 ft El Yunque Peak just to the west around 8 miles and less than 5 miles to the west of the runway is a 1050 ft peak just by reading the aeronautical charts. If you can make an imaginary map of what I just showed, the place is not as "exposed" as you try to make it look like. In fact you'll be interested to read the following information:

Winds measured in Roosevelt Roads during hurricanes Hugo and Georges:

Hurricane Hugo:

90 kts G104 kts from the W

Hurricane Georges:

78 kts G93 kts from 150 degrees or SE

The interesting thing with this report is that as the NHC Preliminary report on hurricane Georges says:

"One of the most important observations reported was in Fajardo, Puerto Rico where the Civil Defense office measured a sustained wind of 96 knots with gusts to 113 knots at 2130 UTC 21 September. Operationally, this report was the basis of making Georges a category 3 hurricane at landfall in Puerto Rico."

Fajardo which was further north reported higher winds. Then Mrs. Kieper can you tell where the logic of all of this goes? This is very simple, the report out of Fajardo was from a more exposed location than that of Ceiba which one would expect had to report similar if not stronger winds during hurricane Georges as they got the NE eyewall which had a stronger signature on the Cayey Radar. Also it was interesting for me to see that the rate of under-estimation for that station for both storms was similar in comparison to the actual intensities that Ceiba might have seen on both hurricanes.

This is assuming Hugo's sustained winds were of 130mph in Ceiba if it were in an unexposed location we get 130-105 = 25 mph lower than winds in the same town at unexposed sites. With hurricane Georges we get 115-90 = 25 mph lower than winds in the same place with at unexposed sites. Even though the wind directions on Hugo and Georges were different for that place, in both times the instrument was blocked by terrain. Also consider that Ceiba was more in the W (and later S) eyewall of Hugo and Rio Grande, Luquillo and Fajardo got more of the N and NW eyewall of the storm by the angle it approached the area. Also notice that the peak winds in Georges were blocked to the anemometer by the afford mentioned 250ft hill ESE of the runway. There is blockage almost everywhere around that runway, you even can see it from highway 53 which lies at a higher altitude west of the base and there are many high trees and forests and mangroves around which further add to the friction problem. So do I have to say more about the quality of the measurement in Roosevelt Roads? Case closed with this one as Jim Leonard says.

continued>>>

 

[Jose Garcia]

>>>cont

<<Also of note is that the minimum pressure at Roosevelt Roads was 946.1 mbar, and occured at 1250Z. The minimum pressure at Luquillo was 956 mbar, noticeably higher, and that occured ten minutes later at 1300Z.>>

The minimal pressure reported in Ceiba of 946mb vs. 956mb in Luquillo can't be compared as it has been stated by the chasers which were the ones who took the measurement that they read that pressure on the barometer much after half the calm during the eye and that at that point the pressure was rapidly rising. So a lower pressure in Luquillo, likely close to the one measured in Ceiba seems very plausible. If not, then we had and "explosively" weakening storm!

<< Do you see the trend? Pressure increasing at every track point, and vmax falling with every track point? Take a look at the mslp-vs-time and vmax-vs-time graphs from the Hugo best track. Hugo weakened for 48 straight hours, from 18/00Z to 20/00Z then strengthened from 20/00Z to 22/00Z, prior to landfall in South Carolina.>>

This example you are trying to use shows that even though you've shown knowledge on TC's (specially coming from a place which doesn't see hurricanes and which is admirable), you still are a long way (as most of us) from understanding many things in regard to the wind/pressure relationship in tropical cyclones. I would like to show you the example of a storm of similar intensity than that of Hugo. It is hurricane Michelle in November 2001. This storm really made me curious about how the winds and pressure in hurricanes relate, then talking with Jim Leonard so many times we've seen that the changes in wind intensity are not as fast as pressure changes. Then a storm with a rapidly falling pressure will have its winds increasing at a rate lower than that of the falling pressure. This has been the case many times and it also happens with rising pressure, in Hugo the pressure was rising in the hours prior to landfall in Puerto Rico, also the satellite signature of the storm did indeed deteriorate compared to 6 hours prior to landfall, but the intensity of the storm was pretty much the same in Puerto Rico than when it passed over St. Croix and this is clearly reflected in the similar damage in the afford mentioned places.

Then why I mention the Michelle example?

Based on the "best track" of hurricane Michelle on NHC's preliminary report:

Michelle's winds increased to a first peak of 115kts with a pressure of 937mb at 03/1200 then the winds leveled off to 110kts and the pressure was actually lower at 934mb at 03/1800. The listed lowest pressure is of 933mb at 03/2100 with 110kts winds. Thereafter the pressure rose constantly until the end of the storm's lifecycle. When the pressure was 11mb higher at 04/0600 the winds were 10 kts higher also at 120kts. I also have to mention that the storm's structure was deteriorating as it approached Cuba until landfall at Cayo Largo (04/1800) but the winds remained at 120kts and the pressure was 16mb higher than at the lowest point !
"Do you see the trend?"
In Hugo similar things happened, the pressure was rising and the satellite presentation was not as good as 6 hours earlier but the winds were still there clearly present with all the evidence of damage and videos. Then the lowering in the winds was evidenced after it moved over Puerto Rico thus supporting the similar wind damage experienced in St. Croix, Vieques, Culebra, Fajardo, Luquillo and Rio Grande and thus showing similar, sustained category 4 hurricane strength winds on these areas.

Based on all of this I estimate Hugo's 1-min winds to be on the 115-120kts range when it hit the NE of Puerto Rico, Culebra and Vieques. The damage by the storm was the worst from Humacao to Rio Grande along the coast and Vieques-Culebra and there are areas of Fajardo, Luquillo and Rio Grande in which the damage looks similar to that done by typhoon Paka in 1997 in Guam. Also going to the San Juan Metro Area there is an unofficial wind gust report of 110mph in Guaynabo around 10 miles WSW of the International Aiport in Carolina. The unexposure of the instruments at the airport were very nicely explained by Richard Horodner and I only want to add that the same problem was experienced during hurricane Georges in 1998.

The airport at SJU reported a max sustained wind of 79mph from the NE with a peak gust of 93mph. The rate of under estimation was also similar to that of what the city saw with hurricane Hugo. The damage in San Juan was similar but a little less intense than on hurricane Hugo so winds of 100mph sustained or maybe more might have been experienced on the city during Georges, again showing the discrepancy between the measurement and the damage experienced.

Mrs. Kieper if you have seen damage done by major hurricanes on tropical areas of the World you would rapidly recognize that the damage done by hurricane Hugo on these areas was that of a major hurricane very likely of category 4 intensity. Even the damage done by category 3 hurricane Georges here in 1998 in the same places (and with actual measurements of cat-3 intensity, Fajardo) were less severe to that of Hugo. Places like Luquillo Beach and close to there, "Los Kioskos" in road #3 which on that part was flooded after Hugo, the damage on the vegetation on the same place compared with pictures and videos after both storms did look less severe after Georges than after Hugo. There is every reason in the world to think Hugo was stronger than Georges here, and that it was a category 4 hurricane.

Jose

 

[Margie Kieper]

The question at hand is, what support exists for these unsubstantiated claims of winds two SSHS Categories above reported windspeeds on mainland Puerto Rico, and one SSHS Category above the best track at the time of the video? There are no actual wind measurements presented to support these claims.

The determination of the max sustained windspeeds in the best track is jointly agreed upon by the NHC forecasters during the post-season analysis, and it is probably safe to assume that because of the multiple landfalls as a major hurricane, Hugo was the focus of much of the post-analysis that season. It appears you want to throw out this expertise, and the entire suite of official reports, wholesale. What methodology, skill level, and validation processes would you use to replace this?

To what do you attribute the difference between your comments

The location of Roosevelt Roads...has el Yunque Montain Range to its West, it has 200-300 ft mountains to its north and a 250 ft hill to the ESE of the runway...the place is not as "exposed" as you try to make it look like.​

and this statement, from the 1994 report, discussing the validity of the readings at this location

The 7-m anemometer at Roosevelt Roads is located adjacent to the main runway and has a clear exposure to wind from all directions.​

I took a close look on Google Earth, and saw that indeed the runway is open and flat, as you would expect a runway to be, and thus an ideal location for measuring windspeeds. I also saw that the end of the runway is about 500 feet from the ocean, and in between it and the ocean is marshland. You neglected to mention that.

The "mountain range" is a distant hill of some 700-800 feet in height. Since the wind readings weren't taken from an anemometer on top of this hill, but instead in a flat open area, boundary-layer flow is not an issue. I'm even more puzzled what you're getting at, if you consider that if an anemometer reading hypothetically was taken in a hilly area where low-slope topography would be a factor, such a topography would serve to artificially increase the measured windspeeds, not lower them, leading to the conclusion that winds must be lower than the recorded measurements, not higher.

 

[Jose Garcia]

<<The question at hand is, what support exists for these unsubstantiated claims of winds two SSHS Categories above reported windspeeds on mainland Puerto Rico, and one SSHS Category above the best track at the time of the video? There are no actual wind measurements presented to support these claims.>>

Maybe its just too hard for you to understand what many experienced people has exposed here with evidence just as obvious as pictures and videos, this clearly shows that you certainly are not able to distinguish damage between major and less intense hurricanes, just keep watching NRL images then.

<<The determination of the max sustained windspeeds in the best track is jointly agreed upon by the NHC forecasters during the post-season analysis, and it is probably safe to assume that because of the multiple landfalls as a major hurricane, Hugo was the focus of much of the post-analysis that season. It appears you want to throw out this expertise, and the entire suite of official reports, wholesale. What methodology, skill level, and validation processes would you use to replace this??>>

If you read well enough you'll see that the general agreement here is of Hugo being a 115-120kts sustained winds hurricane at time of landfall in Puerto Rico which is only 5-10kts in disagreement with the official estimates of intensity (many people disagreed about Andrew's intensity estimate by NHC and it was upped to 145kts in the post analysis, thats 20kts more!). Your 96kts winds in Luquillo estimate made me laugh when I read it and at the very first hand, I though you were talking of 10-min average winds! seriously.


<<To what do you attribute the difference between your comments
The location of Roosevelt Roads...has el Yunque Montain Range to its West, it has 200-300 ft mountains to its north and a 250 ft hill to the ESE of the runway...the place is not as "exposed" as you try to make it look like.
and this statement, from the 1994 report, discussing the validity of the readings at this location
The 7-m anemometer at Roosevelt Roads is located adjacent to the main runway and has a clear exposure to wind from all directions.
I took a close look on Google Earth, and saw that indeed the runway is open and flat, as you would expect a runway to be, and thus an ideal location for measuring windspeeds. I also saw that the end of the runway is about 500 feet from the ocean, and in between it and the ocean is marshland. You neglected to mention that.

The "mountain range" is a distant hill of some 700-800 feet in height. Since the wind readings weren't taken from an anemometer on top of this hill, but instead in a flat open area, boundary-layer flow is not an issue. I'm even more puzzled what you're getting at, if you consider that if an anemometer reading hypothetically was taken in a hilly area where low-slope topography would be a factor, such a topography would serve to artificially increase the measured windspeeds, not lower them, leading to the conclusion that winds must be lower than the recorded measurements, not higher.>>

This is indeed my favorite part of the post. First I want to show you a few pictures from Planepictures of your "exposed" TJNR runway.

These two pictures are taken from road #53 W of the runway and looking eastward. There you can clearly see your "flat" terrain east of the runway and behind those hills is the ocean. Your so-called marshland are mangrove forests between the end of the runway and the beach, I clearly mentioned those in my last post, just to refresh your memory:

I said:

<< There is blockage almost everywhere around that runway, you even can see it from highway 53 which lies at a higher altitude west of the base and there are many high trees and forests and mangroves around which further add to the friction problem.>>

I know you probably know little about this kind of tree because it doesn't exists in cold Minneapolis but these kind of forest grows in the tropical water and near the beaches at many places around Puerto Rico and they are even recognized as natural wind barriers against the prevalent trade winds and hurricanes. Sounds like a lot of friction to me! So I think that I'm not the one "neglecting" the truth of all of this.

continues>>

 

[Jose Garcia]

>>cont>>

As for the "distant" 500-800 ft hill west of the runway. That was quite an amazing comment considering that someone from a "distant" place was going to teach me about the geography of my country and make me reevaluate everything that I learned and personally saw throughout my life, and that just based on a Google Earth image. I mentioned so clearly the El Yunque Mountain Range which starts less than 5 miles due west of the runway with a 1050 ft peak very close to the W of the runway and el Yunque Peak of 3600ft+ a few miles further west. I though this wouldn't be necessary but given your amazing "certainty" about the topography of the area based on google, I'll have to show you the aeronautic charts, the ones pilots actually use to land there.

See by yourself:

There in the chart you can see the before-mentioned 1050 ft peak west of the runway and the 241ft high mountain ESE of the runway, I didn't invent that Mrs. Kieper. There is even a 549 ft hill N of the airport in Fajardo which I know is the Las Croabas-Seven Seas area and which shows that there is only rough terrain around your "exposed" runway. Even the MSA (minimun safe altitude) for TJNR is of 5100 ft to the west and 2700 ft to the east! In other charts of the same runway they warn pilots about the numerous obstacles landing and taking off there. You can also see that the 3637 peak WNW of the field is 10nm of distance and the 1050 ft peak is quite a lot closer, thus showing that it is approximately 3 miles or so from the threshhold of runway 7. And even more impressive are the numerous towers and hills around the runway in the smaller scale map in the lower-right portion of the map were you can see two 400+ ft peaks and one near 300 ft peak and that just outside the runway, also a 211 ft north of the extreme north of the runway 25.

This was indeed the best comment of all:

<<I'm even more puzzled what you're getting at, if you consider that if an anemometer reading hypothetically was taken in a hilly area where low-slope topography would be a factor, such a topography would serve to artificially increase the measured windspeeds, not lower them, leading to the conclusion that winds must be lower than the recorded measurements, not higher.>>

I'm still waiting to see a hurricane in which offshore winds coming from a hilly area actually increase rather than decrease! Heck even in Key West when I chased hurricane Rita in 2005 I could notice a big difference between the onshore wind in the south side and how the winds were a lot weaker just a few blocks inland, and that was even without mountains! In Luquillo the second half of hurricane Hugo was a lot weaker and that was because the wind was coming from inland, from El Yunque, just as what happened to Ceiba but in Luquillo it was with the backside. Winds coming from mountains never increase unless you get an acceleration by topography when the winds go roughly parallel or towards the mountain like what happened in the Caguas Valley during hurricane Georges. Ceiba did not experience this kind of effect during hurricane Hugo. That very last comment showed that you are still far from understanding the behavior of winds during hurricanes in areas with complicated terrain characteristics, remember Mrs. Kieper, this island is not flat as Florida.


In conclusion, there is too much terrain and friction was more than enough to have lowered hurricane Hugo's winds speeds at the location of the instrument, also this is considered after the strongest winds at that location were expected to be from the NW and W, both inland winds at that location which were very likely reduced by the rough terrain and other factors that caused increased friction in that area. That's why Jim filmed Hugo in Luquillo and not in Ceiba! guess were all his expertise in hurricane chasing comes from...

Jose

 

[Margie Kieper]

Jose you still have not provided a scientific explanation why you reject wind readings from this ASOS location, which confirms to siting standards.

Are you saying that you reject the Federal siting standard itself, as being fundamentally flawed or invalid? If this is the case, do you then have a list of airports with ASOS that do not meet your standards? Let's say, for example, the airport in Boulder, CO, which, unlike TJNR, really is near a mountain range.

Since you are so concerned with the accuracy of wind measurements based on local topography and siting, why would you then also mention an unattributed "unofficial" wind reading of 110 mph in one of your posts, where no information at all is provided by you about those specifics?

Can you provide guidelines or documentation for the unique wind standards that you use, to determine which of the wind measurements at various airports or other ASOS locations satisfy your criteria as valid, and which you reject? Does this guideline include the airport at San Juan, which is only approximately 15 miles west of Luquillo and recorded much lower winds than Roosevelt Roads?

Finally, you are aware that the images of the section of the runway that you posted are outside of the area where the weather station facility is located? You keep forgetting to mention there is only ocean, low-lying elevations, and marshland surrounding the bulk of the facility.

 

[Jose Garcia]

<<Jose you still have not provided a scientific explanation why you reject wind readings from this ASOS location, which confirms to siting standards.>>

Not only I, but other people which is a lot more experienced than myself has provided quite a lot of facts which are based on documentation of the storm, this did not come from anyone's imagination. Are you going to talk me about science? Your attitude with this debate is one of negation and resembles more of a frustrated law school student than that of a scientist open to analysis and investigation.

<<Are you saying that you reject the Federal siting standard itself, as being fundamentally flawed or invalid? If this is the case, do you then have a list of airports with ASOS that do not meet your standards? Let's say, for example, the airport in Boulder, CO, which, unlike TJNR, really is near a mountain range.>>

That was really funny to read. First, I'm not questioning that the winds at that point were the instrument was (90kts sustained) was under-measured. You indeed lack of understanding of what I mean by onshore and offshore winds, you certainly lack of knowledge of physical forces like friction, you obviously lack of knowledge about tropical vegetation such as mangroves known for their strength and high rates of friction for wind during hurricanes. Probably Hugo was just a snow storm like the ones that hit your backyard.

El Yunque not a mountain range? wow that's the most brilliant statement I've read in years. No, those 3600ft+ peaks are probably just product of the imagination of the humanity, or just some low cloud layers west of Ceiba, in fact, it doesn't exists if we follow your expertise in aviation, geography, biology, physics, and off course! meteorology.

<<Since you are so concerned with the accuracy of wind measurements based on local topography and siting, why would you then also mention an unattributed "unofficial" wind reading of 110 mph in one of your posts, where no information at all is provided by you about those specifics?>>

If you will know how science works, first you get the data, then you analyze it and then you get conclusions. That's scientific method. I did not say that the report from Guaynabo was accurate or not (neither I care if you accept it or not), I stated that report as a potential indicator of what kind of winds the San Juan Metro Area experienced in Hugo and which coincidentally are close to the frequent 120mph gusts estimated by Horodner in Isla Verde which was further east and in front of the coast.

<<Can you provide guidelines or documentation for the unique wind standards that you use, to determine which of the wind measurements at various airports or other ASOS locations satisfy your criteria as valid, and which you reject? Does this guideline include the airport at San Juan, which is only approximately 15 miles west of Luquillo and recorded much lower winds than Roosevelt Roads?>>

This is another twisted argument. Why? First because San Juan-Carolina (the airport is in Carolina, not San Juan) was outside of the radius of maximum winds of the storm. You obviously haven't even seen a tropical depression from what I can see, when you see a hurricane in the deep tropics, if so, then you will find the difference between the eyewall and outside the eyewall, the winds are a lot stronger, gusts are a lot higher, the rain is almost white-out depending on the storm and is a lot more steady blast than in between rain bands outside the wall cloud. From what I know, Carolina missed the eyewall by just a few miles, and that really makes a world of a difference. Hence you can't compare the winds between both sites, also is not so hard to understand Richard Horodner's good explanation about the exposure of the instruments in both sites when Hugo which incidentally experienced the same situation 9 years later when hurricane Georges.

<<Finally, you are aware that the images of the section of the runway that you posted are outside of the area where the weather station facility is located? You keep forgetting to mention there is only ocean, low-lying elevations, and marshland surrounding the bulk of the facility.>>

Really? I didn't know Minneapolis was so close to Ceiba, thanks for the info then.

In spanish there is this say which is very true:

"No hay peor ciego, que el que no quiere ver."

"There isn't worst blind, that the one who doesn't wants to see."

Jose