Chase Case #15

[Brian Stertz]

I am going to head west and hang out at the Brice-Silverton highway intersection at 256/70 near the Hall/Briscoe Co. line. Need to watch out for the cranky sheriff there. View is good there and something ought to pop very close to the edge of the Caprock and I will nail it.

 

[Jared Farrer]

Still sitting in Canyon, TX. I have to try and resist going south! But the winds are picking up in my area. Things are about to go any minute. I might have to start driving east here in a few.

Hey Paul, you should make wayfaring points for all the tornado reports!? Just name them tornado one, two etc. Or Tornado 1 SD, Tornado TX 2, and so on!? Think thats a good idea?

 

[Corey Sloan]

Headed toward Shamrock, TX from Woodward, OK...most likely will not make it...realistically Mendota, TX will be close....will watch radar trends as I go...

 

[Jeff Duda]

Been heading south from Seiling towards Elk City, OK...looking towards Chickasha, though.

 

[Paul Austin]

Urgent Notice

<3 short crackly tones, 1 long clear tone>

"From the National Weather Service in..."

At 2123z spotters reported a tornado 3 miles east of Tilford, SD.

At 2141z a tornado was reported 4 miles south of Minatare, NE.

At 2157z a tornado was reported 4 miles southeast of Minatare, NE.

At 2200z a tornado was reported 6 miles north of Bayard, NE.

 

[Paul Austin]

22z Update

22Z Observations:


Surface Observations:
Northern Plains
Central Plains
Southern Plains
Eastern CONUS

Visible Satellite Imagery:
National
Northern Plains
Central Plains
Mid-Mississippi Valley

Radar Imagery:
Northern Plains
Central Plains
Southern Plains
Middle Mississippi Valley
Lower Mississippi Valley


Mesoscale Discussions and Weather Watches:

MD 10 Graphic

MESOSCALE DISCUSSION 10NWS STORM PREDICTION CENTER NORMAN OK
0436 PM CDT
AREAS AFFECTED...CENTRAL AND SRN MS...ERN SOUTH LA
CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 2136Z - 2330Z
A WW WILL BE ISSUED SHORTLY. LARGE HAIL AND DAMAGING WINDS WILL BE
POSSIBLE.

LATEST SURFACE ANALYSIS SHOWS WEAK LOW PRESSURE TROUGH EXTENDING
FROM CENTRAL LA EWD INTO SRN MS. MODIFIED 18Z JAN SOUNDING SHOWS
ANYWHERE FROM 2500-3500 MLCAPE VALUES. WLY FLOW AVERAGING 10-15 KTS
IN THE LOWEST 3 KM WILL FEED STORMS WITH STRONG INSTABILITY...WHILE
SUFFICIENT DEEP LAYER SHEAR WILL ALLOW FOR A FEW SUPERCELLS WITH
LARGE HAIL. DAMAGING WINDS WILL BE MORE LIKELY IF LARGE CLUSTER OF
CELLS CAN FORM AND GET AN ORGANIZED COLD POOL GOING. ALTHOUGH AREA
RAOBS AND VWPS SHOW LITTLE IN THE WAY OF SRH...SUPERCELL CHANCES
WILL BE MAXIMIZED WITH SOUTHERLY MOVING CELLS.



MD 11 Graphic

MESOSCALE DISCUSSION 11[FONT=&quot]
[/FONT]NWS STORM PREDICTION CENTER NORMAN OK[FONT=&quot]
[/FONT]0509 PM CDT[FONT=&quot]
[/FONT]AREAS AFFECTED...SD[FONT=&quot]
[/FONT]CONCERNING...SEVERE THUNDERSTORM POTENTIAL [FONT=&quot]

[/FONT]VALID 2209Z - 2345Z[FONT=&quot]
[/FONT]THUNDERSTORMS WILL CONTINUE TO DEVELOP OVER PORTIONS OF SD THIS[FONT=&quot]
[/FONT]EVENING WITH THE THREAT OF LARGE HAIL. WW MAY BE REQUIRED IN THE[FONT=&quot]
[/FONT]NEXT HOUR.[FONT=&quot]

[/FONT]21Z SURFACE ANALYSIS SHOWS A NARROW AXIS OF MID 50 SURFACE DEWPOINTS[FONT=&quot]
[/FONT]EXTENDING FROM WRN KS NWD INTO WRN NEB AND THEN NNEWD INTO CENTRAL/[FONT=&quot]
[/FONT]NERN SD...WHICH IS CONTRIBUTING TO MODERATE INSTABILITY OVER WRN/[FONT=&quot]
[/FONT]CENTRAL SD. A 30-35 KT SLY LLJ OVER THE CENTRAL PLAINS WILL[FONT=&quot]
[/FONT]STRENGTHEN THIS EVENING AND CONTINUE TO TRANSPORT MOISTURE NWD. [FONT=&quot]
[/FONT]THIS COMBINED WITH INCREASING LARGE SCALE ASCENT ASSOCIATED WITH A[FONT=&quot]
[/FONT]SHORT WAVE TROUGH OVER THE NRN ROCKIES WILL RESULT IN ADDITIONAL[FONT=&quot]
[/FONT]THUNDERSTORMS INTO THE EVENING. GIVEN MODERATE INSTABILITY AND[FONT=&quot]
[/FONT]SUFFICIENT DEEP LAYER SHEAR...SUPERCELLS WILL BE LIKELY. STEEP[FONT=&quot]
[/FONT]LAPSE RATES AND WET-BULB ZERO HEIGHTS OF 6-7 KFT WILL SUPPORT LARGE[FONT=&quot]
[/FONT]HAIL. [FONT=&quot]



[/FONT] URGENT - IMMEDIATE BROADCAST REQUESTED[FONT=&quot]
[/FONT]SEVERE THUNDERSTORM WATCH NUMBER 5
NWS STORM PREDICTION CENTER NORMAN OK [FONT=&quot]
[/FONT]445 PM CDT[FONT=&quot]
[/FONT]THE NWS STORM PREDICTION CENTER HAS ISSUED A[FONT=&quot]
[/FONT]SEVERE THUNDERSTORM WATCH FOR PORTIONS OF [FONT=&quot]

[/FONT]NORTHEAST AND SOUTHEAST LOUISIANA[FONT=&quot]
[/FONT]CENTRAL AND SOUTHERN MISSISSIPPI[FONT=&quot]
[/FONT]COASTAL WATERS[FONT=&quot]

[/FONT]EFFECTIVE THIS AFTERNOON AND EVENING FROM 445 PM UNTIL[FONT=&quot]
[/FONT]1000 PM CDT.[FONT=&quot]

[/FONT]HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70[FONT=&quot]
[/FONT]MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.[FONT=&quot]

[/FONT]THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 80 STATUTE MILES[FONT=&quot]
[/FONT]NORTH AND SOUTH OF A LINE FROM 25 MILES WEST NORTHWEST OF NATCHEZ[FONT=&quot]
[/FONT]MISSISSIPPI TO 50 MILES NORTHEAST OF GULFPORT MISSISSIPPI.[FONT=&quot]

[/FONT]REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE[FONT=&quot]
[/FONT]FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.[FONT=&quot]
[/FONT]PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING[FONT=&quot]
[/FONT]WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE[FONT=&quot]
[/FONT]WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE[FONT=&quot]
[/FONT]TORNADOES.[FONT=&quot]

[/FONT]OTHER WATCH INFORMATION...CONTINUE...WW 2...WW 3...WW 4...[FONT=&quot]

[/FONT]DISCUSSION...NW-SE OUTFLOW BOUNDARY FROM EARLIER STORMS IN AL IS[FONT=&quot]
[/FONT]PROVIDING A FOCUS FOR NEW THUNDERSTORM DEVELOPMENT ACROSS CENTRAL[FONT=&quot]
[/FONT]AND SRN MS. THE STORMS WILL BE FORMING AND MOVING SWD INTO AN[FONT=&quot]
[/FONT]ENVIRONMENT CHARACTERIZED BY MLCAPE VALUES OF 2500-3000 J/KG AND 0-6[FONT=&quot]
[/FONT]KM SHEAR MAGNITUDES OF 35-45 KT...WHICH SHOULD SUPPORT SUPERCELLS. [FONT=&quot]
[/FONT]LARGE HAIL WILL BE THE MAIN THREAT...THOUGH DAMAGING WINDS MAY ALSO[FONT=&quot]
[/FONT]OCCUR WHERE STORMS MERGE INTO LARGER CLUSTERS.[FONT=&quot]

[/FONT]AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT[FONT=&quot]
[/FONT]TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60[FONT=&quot]
[/FONT]KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM[FONT=&quot]
[/FONT]MOTION VECTOR 33015.[FONT=&quot]



[/FONT]URGENT - IMMEDIATE BROADCAST REQUESTED[FONT=&quot]
[/FONT]TORNADO WATCH NUMBER 6
NWS STORM PREDICTION CENTER NORMAN OK [FONT=&quot]
[/FONT]410 PM MDT[FONT=&quot]
[/FONT]THE NWS STORM PREDICTION CENTER HAS ISSUED A[FONT=&quot]
[/FONT]TORNADO WATCH FOR PORTIONS OF [FONT=&quot]

[/FONT]EXTREME NORTHEAST COLORADO[FONT=&quot]
[/FONT]WESTERN NEBRASKA[FONT=&quot]

[/FONT]EFFECTIVE THIS AFTERNOON AND EVENING FROM 410 PM UNTIL[FONT=&quot]
[/FONT]900 PM MDT.[FONT=&quot]

[/FONT]TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS[FONT=&quot]
[/FONT]TO 55 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.[FONT=&quot]

[/FONT]THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND WEST[FONT=&quot]
[/FONT]OF A LINE FROM 35 MILES EAST NORTHEAST OF CHADRON NEBRASKA TO 15[FONT=&quot]
[/FONT]MILES SOUTHWEST OF IMPERIAL NEBRASKA.[FONT=&quot]

[/FONT]REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR[FONT=&quot]
[/FONT]TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.[FONT=&quot]
[/FONT]PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING[FONT=&quot]
[/FONT]WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE[FONT=&quot]
[/FONT]WARNINGS.[FONT=&quot]

[/FONT]OTHER WATCH INFORMATION...CONTINUE...WW 2...WW 3...WW 4...WW[FONT=&quot]
[/FONT]5...[FONT=&quot]

[/FONT]DISCUSSION...THREAT FOR SUPERCELLS/TORNADOES WILL INCREASE DURING[FONT=&quot]
[/FONT]THE EVENING ACROSS THE WRN NEB AREA. STRONG PRESSURE FALLS ACROSS[FONT=&quot]
[/FONT]THIS AREA WILL RESULT IN BACKED LOW-LEVEL WINDS/STRONG LOW-LEVEL[FONT=&quot]
[/FONT]SHEAR BENEATH 40-50 KT MID LEVEL FLOW. ALSO...MOISTURE ADVECTION[FONT=&quot]
[/FONT]FROM THE SE WILL RESULT IN DESTABILIZATION ACROSS WRN NEB THROUGH[FONT=&quot]
[/FONT]THE EVENING.[FONT=&quot]

[/FONT]AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL[FONT=&quot]
[/FONT]SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND[FONT=&quot]
[/FONT]GUSTS TO 50 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450.[FONT=&quot]
[/FONT]MEAN STORM MOTION VECTOR 26025.[FONT=&quot]


Chaser Positioning Map


[/FONT]

 

[Paul Austin]

Still sitting in Canyon, TX. I have to try and resist going south! But the winds are picking up in my area. Things are about to go any minute. I might have to start driving east here in a few.

Hey Paul, you should make wayfaring points for all the tornado reports!? Just name them tornado one, two etc. Or Tornado 1 SD, Tornado TX 2, and so on!? Think thats a good idea?

Fantastic idea! I have added the reports to date as notes rather than waypoints, so that they are easier to pick out. They show up as yellow waypoints. Info (what little I have) and times are tagged to each one.


CONCERNING THE MAP: I have recently noticed that the wayfaring maps have trouble loading in some versions of Internet Explorer. I had not noticed this before, as I almost always use Firefox. I am not at this point aware of a fix. So, if you are having difficulty viewing the map, try using a different browser (Firefox, Opera, Netscape, etc.) Sorry if you have been unable thus far to view/use it.

 

[Wes Carter]

Hmmm, it looks like I need to sit here a spell because if this storm does anything, it will be just a few miles to my north. I might need to go south a couple of miles so I don't get core punched, but I think I'm in a pretty good spot. I just hope this one cooks up something for me.

 

[David Wolfson]

Heading south of Turkey toward Matador to get ahead of the developing cell near Floydada. The storm farther south, east of Dickens, is possibly already tornadic by the looks of the radar, but the earliest I could probably catch up to it is north of Aspermont somewhere. I'm targeting the more northerly storm at Glenn, TX, before 23Z. Any of these storms should be in a very favorable environment for further development.

 

[Jim Cross]

Made it to Shamrock for the 22z update. Now heading south on hwy 83 to try to catch the storm developing near Turkey.

 

[Andrea Griffa]

I'm glad to have 3 tornadoes report near Scottbluff,Ne. Now our supercell is getting a bit organized, Im seeing another dark lowering on my SE.

Tx: impressive bulging along the dryline right now. Synoptics ready to explode with the first two supercells forming.

 

[Josh Richardson]

Well my only real choice is to blast towards Ogallala and see if anything else develops or see if there is time to advance north towards the only storm up here. We'll see how it pans out. Bob, you following?

 

[Michael O'Keeffe]

The cell I am on is splitting so I am dropping a little more south to a get a better view of the right split. I will likely find a good east-west road now because I'm guessing this cell will likely begin heading east.

 

[John Erwin]

bah! I'll have to drop out of this one, been too busy to follow this adequately enough.

In any case thanks for an interesting chase scenario Paul!

 

[Bob Hartig]

The northeast Colorado shuttle bus is embarking for points north, up to Chappel, NE, as fast as I can scoot.

EDIT: Josh, just saw your note. Good hunting over in Ogallala. I'm looking at that patch of cloud sluicing into the NW corner of the NE panhandle out of CO, at least for now. Don't see anything likelier in the neighborhood at the moment. Realistically, at this point, all targets are on the fly and negotiable. I'll take what comes. Just nice to see the tornado watch in our neck of the woods. And on second thought, make that Lodgepole, not Chappel. Kicking myself for not going with Verne to begin with--he's got the copter!