8/27/04 FCST: Frances (Atlantic)

[B Ozanne]

Sorry to disagree, but why do you say that, Bill?

In reference to SST's. I noticed that graphic was from the 21st. I believe there was a significant frontal passage right around that time. Temperatures barely reached 70 degrees in NYC last week. On a short term basis that can have an effect on SST's. Notice how the negative anomalies are close to shore and mirror where a front might be. They also lie in Charley's path.

Now my initial claim of high SST's was from a first hand account. I've been vacationing in NJ for 15 years and have never felt 80 degree water there. Earlier this month the water was 80. I'm not sure whether or not those conditions still exist, but historically water temps are just peaking in this area.

I should also mention the rapid formation and intensification of Alex. It reached CAT 3 at an extreme northerly latitude. The formation of Gaston. And the up and coming TD 8 (Stay tuned). All have formed relatively far north. I would look at that graphic with a big grain of salt because one of the big discussions this summer on the east coast was how warm the water has been.

 

[Robert Dewey]

I have to agree with the water temeratures being above average. Most of the Atlantic is experiencing +0.5C to +1.0C above average. The only areas that are below average, appear to be right along the cost line. This is probably because the water is more shallow along the coast-line, allowing for the air temperature to have more of an effect on it (in this case, cooling). Water temperatures towards New England and up towards Nova Scotia are much above averate (+3.0C). Which is also interesting because, there is a theory (Joe Bastardi, Accuweather) that would indicate warm water pooling in this region would tend to indicate that the average NAO phase would be negative - Which I believe so far has been true.

 

[B Ozanne]

Maybe a good discussion would be: where would you put yourself 24 hours before landfall? You obviously want to be near where the eye is going to hit. You also want to be in a good position to move if the course changes, and you don't want to be held back by a mass evacuation.

I have no intention of chasing this 'cane, but it's fun to armchair it, especially this far out. You have to consider the possibility of mandatory evacuations. If you are already on a barrier island you might be okay, but if the mandatory evac goes into effect they won't let you onto those islands. Especially if you don't have local ID.

Right now I'd pick Savannah, GA. That puts me 10 hours from Virginia Beach and 10 hours from the middle Keys.

 

[Bob Schafer]

The 1945Z imagery from the GHCC site, and which allows you to determine estimated position, puts the eye at 19.0N 55.2W.

TPC's forecast positions called for Frances to reach 56.1W before reaching 19.0N.

This would represent a significant poleward departure from her forecast track, but in reality is likely nothing more than an eye wobble, particularly in light of the much more asymetric shape that has evolved in the past 24 hours. The eye is not as well defined, nor as large, attm, either.

It makes me wonder if Frances has lost some strength.

I can't wait for the 21Z update, and data from the hunter plane.

Bob

[edit:] 2015Z imagery puts the eye at 19.0N 55.3W, so I guess the eye is, in fact, wobbling.

Oh, also, interesting discussion about the SST's. Makes sense.

 

[Mike Johnson]

If I had to bet right now, based on an averaging of models, I'd say the Daytona Beach area sometime Sunday. It will be nice to see the next
2 updates with the addition of the NOAA jet data.

It's important to remember this is Labor Day weekend. I can
only imagine what must be going through emergency managers heads
right now, with the "holiday factor" in the mix. Does anyone know if
there are any mega events along the Florida or other East Coast
locations this weekend? This could be a REAL serious problem as massive evacuations are compounded with holiday travelers who will need to return and/or divert.

(Chasers might also want to plan ahead an extra day or so).

Mike

 

[Carrie Halliday]

As far as the holiday factor, I agree Mike. Nightmare scenario. Frances looks to me like she just may want a taste of the Gulf. Wishful thinking maybe, been pretty quiet on my side of Gulf this year. I had it in my head we were only prime in June but forgot the biggest and deadliest 'cane on the western Gulf hit in September.

 

[Glen Romine]

[edit:] 2015Z imagery puts the eye at 19.0N 55.3W, so I guess the eye is, in fact, wobbling.

Bob, I think there is a bit of parallax error in using the sat image for eye placement as well. Because the sat is looking at the hurricane at an angle, and you are seeing the "hole" well above the surface, the true circulation center at the ground is going to be biased slightly south of the center. That is probably why the official eye placement differs (southward ~ 0.2 degrees).

Glen

 

[Thomas Loades]

The NHC says Frances is now down to a cat-3 with 120-mph winds and central pressure of 958 mb, but there's still a lot of ocean to go until it reaches the U.S., and she still looks nasty in the satellite pictures.

 

[Joel Wright]

I look for it to start to get stronger, possibly as high as a high end cat 4 before it begins to weaken while it makes the right turn towards the Carolinas. Hopefully it weakens to a cat 2 at least before it threatens there.

 

[Glen Romine]

The big change is the GFS now forecasts a strong shortwave trough in the zonal flow to be moving across the Ohio Valley as the hurricane approaches. Apparently this is creating -- in the model world -- enough of a weakness in the subtropical ridge to enduce a poleward motion. Will be intersting to watch the trends.

Yeah, I see the same thing - and this pattern is continued in the latest runs. Funny all the talk of the value in the synoptic soundings in improving the track forecast - but that only helps for the next ~ 3 days. Beyond that - the track is likely to be heavily reliant on the strength of the trough forecast to emerge into the central plains. This system is currently still in the Gulf of Alaska - where no wx balloons are launched obviously - so the timing and intensity of this wave is suspect to say the least. Picking a landfall location at this point is akin to dart throwing - but if you want to literally interpret the model guidance landfall looks to be Monday, Sept 6 in the South Carolina coast. I'd recommend holding off on those hotel reservations just yet though...... since this is near the predictability limit of the GFS model.

http://www.emc.ncep.noaa.gov/gmb/tpm/emchu...noam.single.gif

Glen

 

[Kevin Scharfenberg]

Interestingly, the 12Z eta valid at 00Z/3rd shows the upper trough cutting off into a moderately strong upper low over the southern Plains, unlike the 06Z GFS valid at the same time. Compare (these links not valid after 3am CDT Tuesday the 31st):

http://www.nco.ncep.noaa.gov/pmb/nwprod/an...ta_300_084l.gif
http://www.nco.ncep.noaa.gov/pmb/nwprod/an...fs_300_090l.gif

Downstream of the low/trough, notice how in the GFS the 40 kt westerlies are as far south as southern NC, but are only into southern VA in the eta model with much more anticyclonic curvature to the flow over and around GA. If the eta is onto something, steering will be really weak, arguing for less poleward motion and a lot of headaches.

 

[Bridget Beddow]

Picking a landfall location at this point is akin to dart throwing - but if you want to literally interpret the model guidance landfall looks to be Monday, Sept 6 in the South Carolina coast. I'd recommend holding off on those hotel reservations just yet though...... since this is near the predictability limit of the GFS model.

I'm just preparing for a labor day weekend/hurricane party just in case.

This has been a REALLY interesting year as far as hurricanes and tropical storms are concerned.

My bet is right in between NC and SC (more towards Wilmington) with a track taking the eye over Kinston or within a 30 mile radius of Kinston area. But I'm as far from forecasting as my brother is from being a girl...it's just my gut feeling....

 

[David Wolfson]

Yeah, Kevin. It looks like the 12Z GFS is starting to settle the same way. Man, that's one ugly track! :cry: Look how big, beefy remnants dawdle straight up through the heart of the Appalachians. Potentially catastrophic flood event. FWIW, my "gut" respects this run as a mezzo-middle resolution.

 

[Kevin Scharfenberg]

The 12Z runs are in, and the guidance is now in better agreement on a Florida landfall within 24 hours of Saturday 18Z. This is due to stronger signature of anticyclonic curvature to the flow aloft with the ridge axis from JAX-HSV. In theory, the hurricane should stay on the equatorward side of the ridge axis.

The GFDL is the right-most, showing a landfall at a large angle to the coast near JAX, while the GFS and UKMET drive the storm WNW to NW with a landfall near PBI. The Canadian model is in-between, showing a large-angle landfall near MLB. This kind of guidance agreement is unusual at day 5, so I wouldn't be surprised to see NHC shift their afternoon outlook to the left. Now, it will be interesting to see if the models can continue to show good agreement for multiple runs.

 

[Glen Romine]

Right Kevin, despite the agreement, the run-to-run consistency leaves a lot to be desired. I don't know of a good plot of the that for tropical regions, but here are some of the new cyclone paths from the 12Z run:

http://www.emc.ncep.noaa.gov/gmb/tpm/emchu...noam.single.gif

Comparing with the earlier GFS run (6 hrs prior), this is a considerable equatorward shift in the latter portion of the track - so while clustering adds confidence, the suspense should continue to build. The latest NCEP forecast seems to be a compromise.

http://www.hpc.ncep.noaa.gov/medr/5dayfcst_wbg.gif

Glen