View Full Version : Severe Weather Risk - 9/21/09



venture
09-21-2009, 12:06 AM
Been awhile for one of these.

Reference sites:

http://www.srh.noaa.gov/oun/enhanced.php

http://www.spc.noaa.gov/

http://weather.cod.edu/data/satellite/1km/Oklahoma.gif

http://weather.cod.edu/data/nexrad/Oklahoma.gif

venture
09-21-2009, 12:06 AM
http://www.spc.noaa.gov/products/outlook/day1otlk_1200.gif

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1257 AM CDT MON SEP 21 2009

VALID 211200Z - 221200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN KS/WRN MO SWWD THROUGH
CENTRAL/ERN OK TO N TX THIS AFTERNOON AND EVENING...

...SYNOPSIS...
MODELS REMAIN CONSISTENT INDICATING UPPER TROUGH...CURRENTLY
AMPLIFYING SSEWD THROUGH THE NRN HIGH PLAINS...WILL BECOME CUT-OFF
FROM PRIMARY BELT OF WESTERLIES TODAY AS AN UPPER RIDGE BUILDS NEWD
ACROSS THE PACIFIC NW INTO WRN CANADA AND NRN HIGH PLAINS. THE
STRONGEST HEIGHT FALLS/DYNAMIC FORCING FOR ASCENT IS FORECAST TO
SPREAD SWD OVER THE CENTRAL/SRN ROCKIES AND ADJACENT HIGH PLAINS.
AT THE SURFACE...A STRONG COLD FRONT ACCOMPANYING THE UPPER SYSTEM
WILL SERVE AS THE PRIMARY FOCUS FOR STRONG TO SEVERE TSTM
DEVELOPMENT THIS AFTERNOON INTO THE EVENING ACROSS THE SLIGHT RISK
AREA. A SECONDARY COLD FRONT WILL SURGE SWD FROM THE CO HIGH PLAINS
THROUGH THE SRN HIGH PLAINS TO FAR NRN MEXICO BY 12Z TUESDAY.

...ERN KS/WRN MO TO SRN PLAINS...
A LEAD SHORTWAVE TROUGH WILL SPREAD ENEWD ACROSS THE MID MO VALLEY
AND ALSO EWD ACROSS THE CENTRAL/SRN PLAINS. SLY LOW LEVEL FLOW WILL
ADVECT MOISTURE NWD AHEAD OF THE COLD FRONT ADVANCING EWD TO WRN
IA...ERN KS AND CENTRAL OK BY MID AFTERNOON. THIS MOISTURE COMBINED
WITH SURFACE HEATING AND ERN EXTENT OF AN EML SUGGESTS A MODERATELY
UNSTABLE AIR MASS /MLCAPE 1500-2500 J/KG/ WILL DEVELOP BY AFTERNOON.
THE STRONGEST INSTABILITY SHOULD BE LOCATED OVER SRN OK/N TX.

AT 12Z TODAY...TSTMS SHOULD BE ONGOING FROM THE MID MO VALLEY INTO
PARTS OF THE CENTRAL PLAINS ALONG THE COLD FRONT AND WITHIN LOW
LEVEL WAA REGIME. ADDITIONAL STORMS ARE EXPECTED TO DEVELOP SSWWD
ALONG THE COLD FRONT AS STRONGER FORCING FOR ASCENT ATTENDANT TO THE
LEAD SHORTWAVE TROUGH SPREADS ACROSS THE CENTRAL/SRN PLAINS...AIDING
IN THE EROSION OF CONVECTIVE INHIBITION. STRONGER DEEP LAYER SHEAR
IS EXPECTED TO LAG THE COLD FRONT. ALTHOUGH MODELS SUGGEST STORMS
SHOULD DEVELOP ALONG AND WITHIN THE POST-FRONTAL ENVIRONMENT...THERE
IS SOME INDICATION FOR STORMS TO DEVELOP WITHIN THE WARM SECTOR...
ESPECIALLY ACROSS ERN OK SWWD INTO N TX. IF STORMS CAN DEVELOP
AHEAD OF THE COLD FRONT...VEERING OF WINDS WITH HEIGHT IN THE LOWEST
3 KM AGL COMBINED WITH EFFECTIVE BULK SHEAR /30-35 KT/ SUGGEST A FEW
SUPERCELLS WOULD BE POSSIBLE WITH A POTENTIAL TORNADO THREAT.
OTHERWISE...LINEAR FORCING ALONG THE COLD FRONT SHOULD SUPPORT A
THREAT FOR DAMAGING WINDS AND HAIL.

...SRN HIGH PLAINS...
THE COMBINATION OF THE SECONDARY COLD FRONT...OROGRAPHIC UPSLOPE AND
INCREASING DEEP ASCENT AHEAD OF SWD MOVING CLOSED LOW MAY SUPPORT
ISOLATED TO SCATTERED STORMS ALONG OR MORE LIKELY IN WAKE OF SURFACE
BOUNDARY THIS AFTERNOON INTO THE EVENING. ALTHOUGH STRONG
UNIDIRECTIONAL SHEAR IS EXPECTED OVER THIS REGION...WEAK INSTABILITY
SHOULD LIMIT THE COVERAGE OF STRONG TO SEVERE STORMS. THESE WILL BE
CAPABLE OF PRODUCING LOCALLY STRONG WIND GUSTS AND HAIL GIVEN STEEP
LAPSE RATES.

..PETERS/GRAMS.. 09/21/2009

kevinpate
09-21-2009, 04:36 AM
Not so good for the fair folks but let it piddle puddle and pour today if it wants to. The yard's been mowed, not planning on being at the lake, a long rain today would be a welcome event.

Thunder
09-21-2009, 04:55 AM
On my day off, I can sit back and watch anything interesting form. Maybe a funnel will drop down a few blocks away from Venture again? :-P

venture
09-21-2009, 10:43 AM
http://www.spc.noaa.gov/products/outlook/day1otlk_1630.gif

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1128 AM CDT MON SEP 21 2009

VALID 211630Z - 221200Z

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY
TONIGHT FROM SW MO ACROSS OK INTO N TX...

...SYNOPSIS...
A MID-UPPER SPEED MAX OVER WRN WY/ERN UT/WRN CO THIS MORNING WILL
DIG SSEWD WHILE THE BROADER SYNOPTIC SYSTEM EVOLVES INTO A CLOSED
MID LEVEL LOW OVER THE HIGH PLAINS THROUGH TONIGHT. AN ASSOCIATED
SURFACE COLD FRONT WILL CONTINUE TO MOVE EWD ACROSS ERN KS/IA/WRN
MO...AND SEWD ACROSS OK AND NW TX THROUGH EARLY TUESDAY. THIS FRONT
WILL SERVE AS THE PRIMARY FOCUS FOR THUNDERSTORM DEVELOPMENT THROUGH
THE PERIOD.

...SRN PLAINS THIS AFTERNOON/EVENING...
BOUNDARY LAYER DEWPOINTS OF 65-70 F HAVE RETURNED NWD IN ADVANCE OF
THE COLD FRONT ACROSS TX/OK/SE KS...BENEATH A PLUME OF 7 C/KM MID
LEVEL LAPSE RATES. THE COMBINATION OF ASCENT ALONG THE FRONT AND
DAYTIME HEATING WILL REMOVE THE CONVECTIVE INHIBITION NOTED IN
REGIONAL 12Z SOUNDINGS AND SUPPORT SURFACE-BASED THUNDERSTORM
DEVELOPMENT ALONG THE FRONT AROUND EARLY-MID AFTERNOON
ACROSS KS/OK. CONVECTION IS THEN EXPECTED TO DEVELOP SWD ALONG THE
FRONT TO NEAR THE RESIDUAL LEE CYCLONE TRIPLE POINT IN NW TX...AND
THEN SPREAD SEWD ACROSS CENTRAL/ERN OK AND N/NE TX THIS EVENING INTO
EARLY TONIGHT. THE MORNING ELEVATED THUNDERSTORMS AND CLOUDS OVER
ERN KS WILL TEND TO LIMIT DESTABIZATION TO THE N OF OK THIS
AFTERNOON.

THE EVOLUTION OF THE SYNOPTIC SYSTEM SUGGESTS THAT THE STRONGEST
LOW-MID LEVEL ASCENT AND DEEP LAYER VERTICAL SHEAR WILL BE CONFINED
TO AREAS ALONG AND W OF THE SURFACE COLD FRONT. THIS...COMBINED
WITH DEEP LAYER FLOW/SHEAR LARGELY PARALLEL TO THE FRONT...AND
FRONTAL MOTION TO THE E/SE THAT IS THE SAME OR FASTER THAN CELL
MOTIONS...SUGGESTS THAT CONVECTION WILL LIKELY EVOLVE INTO AN
EXTENSIVE FRONTAL SQUALL LINE BY THIS EVENING. LARGE HAIL AND
DAMAGING WINDS WILL BE THE MAIN CONCERNS AS A RESULT OF RATHER
MODEST WARM SECTOR VERTICAL SHEAR AND AFTERNOON MLCAPE VALUES OF
2000-3000 J/KG.

westsidesooner
09-21-2009, 10:57 AM
It looks like the front is along a line from Enid to Clinton as of noon, and making pretty good progress se. It'll be hard to follow today, there seems to be several glitches on the NWS radar and the Rap/ucar satelite. I'm not expecting much....but we'll see.

SoonerDave
09-21-2009, 11:10 AM
So it still looks like we're talking a potential for rough weather here in the Metro right around the 5pm hour or thereabouts?

Argh...

Thunder
09-21-2009, 11:35 AM
NWS called for isolated tornadoes. Karrie?

venture
09-21-2009, 11:58 AM
NWS called for isolated tornadoes. Karrie?

It is a 2% or less risk today. Don't think too much of it.

venture
09-21-2009, 12:30 PM
http://www.spc.noaa.gov/products/md/mcd2023.gif

MESOSCALE DISCUSSION 2023
NWS STORM PREDICTION CENTER NORMAN OK
0126 PM CDT MON SEP 21 2009

AREAS AFFECTED...CENTRAL AND ERN OK/SWRN MO/NWRN AR/N TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 211826Z - 212030Z

INCREASING SEVERE POTENTIAL ACROSS THIS REGION OVER THE NEXT COUPLE
OF HOURS COULD REQUIRE WW ISSUANCE.

LATEST SURFACE ANALYSIS SHOWS A SEWD-MOVING COLD FRONT STRETCHING
ROUGHLY FROM FAR SERN NEB SSWWD TO JUST E OF ICT /WICHITA KS/...AND
THEN SWWD ACROSS NWRN OK INTO THE SERN TX PANHANDLE. ANALYSIS ALSO
DEPICTS A PRE-FRONTAL WIND SHIFT...PARALLEL TO AND ROUGHLY 50 MI
AHEAD OF THE MAIN FRONT.

THE PRE-FRONTAL BOUNDARY LAYER HAS MOISTENED OVER THE PAST SEVERAL
HOURS...WHERE DEWPOINTS ARE NOW INTO THE UPPER 60S TO LOW 70S. THIS
COMBINED WITH DAYTIME HEATING HAS YIELDED SURFACE-BASED CAPE IN
EXCESS OF 2000 J/KG ALONG WITH A SLOWLY WEAKENING CAPPING INVERSION.
A LINE OF SLIGHTLY ELEVATED STORMS CONTINUES MOVING ACROSS FAR SERN
KS AND INTO ADJACENT WRN MO...WHICH COULD BECOME SURFACE-BASED WITH
TIME AS THE PRE-CONVECTIVE BOUNDARY LAYER CONTINUES DESTABILIZING.
MEANWHILE...STORM DEVELOPMENT HAS BEGUN TO INCREASE ACROSS N CENTRAL
AND NERN OK AND ADJACENT PARTS OF KS...WHICH SHOULD EXPAND SWWD
ALONG THE PRE-FRONTAL WIND SHIFT AND/OR SURFACE FRONT OVER THE NEXT
FEW HOURS.

DEEP-LAYER SHEAR -- WHILE NOT PARTICULARLY STRONG -- APPEARS
SUFFICIENT FOR ORGANIZED/WEAKLY-ROTATING STORMS. INITIAL CONVECTIVE
DEVELOPMENT MAY EXHIBIT SOME SUPERCELL CHARACTERISTICS...BUT
EVENTUAL EVOLUTION INTO LINEAR ORGANIZATION SHOULD OCCUR. GENERALLY
VEERED LOW-LEVEL FLOW SUGGESTS LIMITED TORNADO POTENTIAL...WITH
GREATER SEVERE POTENTIAL LIKELY TO BE HAIL INITIALLY...AND THEN MORE
LIKELY TO INCLUDE LOCALLY-DAMAGING WINDS AS LINEAR STORM MODE
EVOLVES.

venture
09-21-2009, 01:02 PM
Spc aww 211857
ww 742 severe tstm ar ks mo ok tx 211900z - 220300z
axis..75 statute miles east and west of line..
50nnw sgf/springfield mo/ - 40sse sps/wichita falls tx/ ..aviation coords.. 65nm e/w /37nnw sgf - 38sse sps/ hail surface and aloft..2 inches. Wind gusts..60 knots.
Max tops to 500. Mean storm motion vector 26025.

http://www.spc.noaa.gov/products/watch/ww0742_radar.gif

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 742
NWS STORM PREDICTION CENTER NORMAN OK
200 PM CDT MON SEP 21 2009

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

EXTREME NORTHWEST ARKANSAS
SOUTHEAST KANSAS
SOUTHWEST AND CENTRAL MISSOURI
CENTRAL AND EASTERN OKLAHOMA
EXTREME NORTHWEST TEXAS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 200 PM UNTIL
1000 PM CDT.

WIDELY SCATTERED DAMAGING WINDS
ISOLATED WIND GUSTS TO 70 MPH POSSIBLE
SCATTERED LARGE HAIL TO 2.0 INCHES IN DIAMETER
ISOLATED TORNADOES

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75
STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH
NORTHWEST OF SPRINGFIELD MISSOURI TO 40 MILES SOUTH SOUTHEAST OF
WICHITA FALLS TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).

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

DISCUSSION...THUNDERSTORMS WILL GRADUALLY INCREASE IN
COVERAGE/INTENSITY ACROSS MO/SE KS AND OK THIS AFTERNOON AS THE LOW
LEVELS CONTINUE TO DESTABILIZE IN ADVANCE OF A COLD FRONT AND
PRE-FRONTAL TROUGH. DEEP LAYER VERTICAL SHEAR IS SOMEWHAT MARGINAL
FOR SUPERCELLS IN THE WARM SECTOR...WHILE MLCAPE VALUES RANGE FROM
2000-3000 J/KG BASED ON SURFACE TEMPERATURES IN THE 80S WITH
BOUNDARY LAYER DEWPOINTS OF 68-70 F. IT APPEARS THAT LARGE HAIL AND
DAMAGING WINDS WILL BE THE MAIN SEVERE THREATS THIS AFTERNOON. THE
SEVERE THREAT WILL CONTINUE INTO THIS EVENING AND EARLY TONIGHT AS
STORMS GRADUALLY EVOLVE INTO AN EXTENSIVE BAND ALONG THE FRONT AND
SPREAD EWD/SEWD.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 26025.

venture
09-21-2009, 02:41 PM
Front is pushing through the western sides of the Metro area. Severe threat appears as though it will be limited to SE of I-44...and further SE of the OKC metro by 6pm. Could still see some popup showers and storms behind the front, but they shouldn't get to crazy except for some heavy rain and maybe some small hail due to the colder air aloft.

venture
09-21-2009, 02:43 PM
Bulletin - immediate broadcast requested
severe thunderstorm warning
national weather service norman ok
341 pm cdt mon sep 21 2009

the national weather service in norman has issued a

* severe thunderstorm warning for...
Southeastern mcclain county in central oklahoma...
Southeastern pottawatomie county in central oklahoma...
Extreme northwestern pontotoc county in east central oklahoma...

* until 445 pm cdt

* at 341 pm cdt...national weather service radar indicated a severe
thunderstorm 3 miles southwest of asher...moving northeast at 25
mph.

Hazards in the warning include...
Hail up to the size of quarters...
Wind gusts to 60 mph...

* locations in the warning include asher...maud...st. Louis and
wanette.

venture
09-21-2009, 04:07 PM
Bulletin - immediate broadcast requested
severe thunderstorm warning
national weather service norman ok
500 pm cdt mon sep 21 2009

the national weather service in norman has issued a

* severe thunderstorm warning for...
Southeastern cleveland county in central oklahoma...
Southwestern pottawatomie county in central oklahoma...

* until 600 pm cdt

* at 500 pm cdt...national weather service radar indicated a severe
thunderstorm 9 miles south of etowah...moving northeast at 15 mph.

Hazards in the warning include...
Hail up to the size of quarters...
Wind gusts to 60 mph...

* locations in the warning include etowah...macomb...tribbey and
trousdale.

Thunder
09-21-2009, 04:26 PM
It is a 2% or less risk today. Don't think too much of it.

I know. I want to see Karrie's reaction, because I think it's quite cute and we all do just love seeing her reaction.

westsidesooner
09-21-2009, 04:48 PM
Thats a pretty potent cold front. It's 43 degrees with a north wind of 38mph in Boise City right now. Trinidad Colorado is sitting at 35 degrees with light snow. Goota love it.

venture
09-21-2009, 05:26 PM
I'm ready for some snow. :-P

Thunder
09-21-2009, 07:57 PM
I'm ready for some snow. :-P

Me too, and I'm expecting that MORE LIKELY and MUCH MORE AMOUNT for this Winter with the El Nino getting stronger.

venture
09-25-2009, 10:50 AM
Quick bump for today.

http://www.spc.noaa.gov/products/outlook/day1otlk_1630.gif

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1107 AM CDT FRI SEP 25 2009

VALID 251630Z - 261200Z

...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF SRN KS AND NWRN
OK...

...NWRN OK AND SRN KS...
RESIDENT UPPER LOW THIS MORNING LOCATED SWRN CORNER NE/CO
BORDER...WILL FINALLY RESPOND TO INCREASINGLY WESTERLIES ACROSS SRN
CANADA AND BEGIN THE EJECTION PROCESS TODAY. VORT LOBE THAT HAS
ROTATED AROUND LOW MOVING SWD THRU ERN CO WILL HEAD EWD ACROSS SRN
KS/NRN OK LATER THIS AFTERNOON/EVENING.

WEAK SURFACE LOW SWRN KS WITH TROUGH EXTENDING INTO TX PANHANDLE
WILL PROVIDE A FOCUS FOR SURFACE BASED CONVECTIVE INITIATION BY
MID/LATE AFTERNOON AS THIS FEATURE SHIFTS EWD ACROSS WRN KS INTO
NWRN OK. WITH STEEP LAPSE RATES ASSOCIATED WITH COLD CORE UPPER
CIRCULATION AND STRONG LOW LEVEL HEATING...COUPLED WITH 35-40KT OF
DEEP LAYER SHEAR...CONDITIONS WILL BE IN PLACE FOR A FEW SEVERE
THUNDERSTORMS. EARLIER FORECASTS KEPT SVR PROBS AT A MINIMUM DUE TO
EXPECTED LIMITED INSTABILITY...MLCAPE AOB 500 J/KG. HOWEVER WITH
OBSERVED LOW 50 DEWPOINTS AND PWAT OF ABOUT .70 IN...SBCAPE TO 1000
J/KG COULD DEVELOP IN AREAS OF FULL HEATING BY MID AFTERNOON FROM
SCENTRAL KS INTO NWRN/NCENTRAL OK. THUS HAVE INCREASED THE THREAT
OF LARGE HAIL AND AS A RESULT ADDED A LOW END SLIGHT RISK FOR THE
AREAS EXPECTED TO DESTABILIZE THE GREATEST AHEAD OF SURFACE TROUGH.
WHILE SHEAR IS SUFFICIENT FOR ROTATING UPDRAFTS...THE MARGINAL
AMOUNT OF INSTABILITY LIMITS ANY TORNADO THREAT TO A POSSIBLE
BRIEF/ISOLATED OCCURRENCE. SUNSET SHOULD LEAD TO A QUICK END OF ANY
SEVERE THREAT.

bretthexum
09-25-2009, 12:17 PM
I'm watchin next Thurs-Fri. Could get interesting... :)

venture
09-25-2009, 12:58 PM
http://www.spc.noaa.gov/products/md/mcd2030.gif

MESOSCALE DISCUSSION 2030
NWS STORM PREDICTION CENTER NORMAN OK
0132 PM CDT FRI SEP 25 2009

AREAS AFFECTED...PORTIONS S-CENTRAL KS...NWRN AND EXTREME W-CENTRAL
OK...ERN PARTS OF TX PANHANDLE.

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 251832Z - 252030Z

SVR POTENTIAL SHOULD INCREASE OVER DISCUSSION AREA THROUGH
MID-AFTERNOON AS BAND OF CONVECTION INTENSIFIES AND TRANSLATES EWD
OVER AREA.

SFC ANALYSIS SHOWS DIFFUSE LOW OVER N-CENTRAL KS VICINITY
RSL-HLC...WITH COLLOCATED SFC TROUGH AND WEAK COLD FRONT SWWD TO
BETWEEN DDC-PTT...AND WSWWD ACROSS EXTREME NWRN TX PANHANDLE.
MEANWHILE...MID-UPPER LEVEL SHORTWAVE TROUGH IS PIVOTING SEWD FROM
SERN CO...WITH ASSOCIATED BELT OF DVPA/ASCENT EXPECTED TO OVERTAKE
COLD FRONT AND CONTRIBUTE TO PREFRONTAL CONVECTIVE ENVIRONMENT
DURING REMAINDER AFTERNOON. PREFRONTAL BAND OF TSTMS HAS BEEN
INCREASING IN COVERAGE AND INTENSITY DURING PAST COUPLE HOURS FROM
ERN TX PANHANDLE NEWD OVER PORTIONS S-CENTRAL KS. THIS ACTIVITY HAS
BEEN ELEVATED...BASED ON MODIFIED RAOBS...RUC SOUNDINGS...AND
SPECKLED ECHO CHARACTER AND RELATIVELY FAST MOVING NATURE OF
INDIVIDUAL CELLS. HOWEVER...GRADUAL STRENGTHENING OF TSTMS IN THIS
BAND IS EXPECTED...WITH SOME TSTMS PRODUCING SVR HAIL AND ISOLATED
STG-SVR GUSTS. THIS WILL OCCUR AS PROSPECTIVE INFLOW LAYER HEATS
DIABATICALLY THROUGH MID-AFTERNOON AND EFFECTIVE LIFTED PARCELS
BECOME SFC-BASED. MOISTURE WILL REMAIN MRGL...WITH SFC DEW POINTS
MIXING INTO MID-UPPER 40S F AHEAD OF PRECIP BAND. ACCORDINGLY
MODIFIED RUC SOUNDINGS YIELD MLCAPE IN 500-1000 J/KG
RANGE...CONSIDERABLY MORE THAN AUTOMATED MESOANALYSES ARE INDICATING
SO FAR BECAUSE OF BACKGROUND RUC TENDENCY TO DRY THIS SFC
ENVIRONMENT TOO MUCH AND TOO FAST. STG UPPER LEVEL FLOW WILL HELP
TO OFFSET SWLY SFC WINDS...IN SUPPORT OF AT LEAST MRGL DEEP-LAYER
SHEAR FOR SVR. EVEN WITH MIXING NOT AS INTENSE AS
PROGGED...INVERTED-V THERMODYNAMIC PROFILE IN LOW LEVELS WILL AID
POTENTIAL FOR SVR HAIL AND DAMAGING GUSTS TO REACH SFC.

..EDWARDS.. 09/25/2009

venture
09-25-2009, 02:28 PM
http://www.spc.noaa.gov/products/outlook/day1otlk_2000.gif

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0234 PM CDT FRI SEP 25 2009

VALID 252000Z - 261200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE TX
PANHANDLE AND NWRN OK...

...TX PANHANDLE/NWRN OK/SCNTRL KS...

HAVE MADE MINOR ADJUSTMENTS TO EARLIER OUTLOOK ACROSS THE SRN/CNTRL
PLAINS REGION. LATEST DIAGNOSTIC DATA SUGGESTS BUOYANCY WILL PLAY
AN IMPORTANT ROLE IN ROBUST UPDRAFT DEVELOPMENT...AND THIS HAS
SHIFTED/DEVELOPED FARTHER SOUTH THAN EXPECTED AT 1630Z. THICK
LAYERED CLOUDINESS...ALONG WITH PRECIPITATION...HAS IMPEDED SFC
HEATING AHEAD OF COLD FRONT ACROSS MUCH OF KS WITH THE STRONGEST
INSTABILITY LOCATED ACROSS THE TX PANHANDLE INTO NWRN OK. THIS IS
COINCIDENT WITH STEEPER LAPSE RATES BENEATH SRN LOBE OF COOLEST MID
LEVEL TEMPERATURES. VIS SATELLITE IMAGERY SUPPORTS THIS WITH
SCATTERED THUNDERSTORM ACTIVITY LOCATED ACROSS NWRN OK...SWWD INTO
THE NERN TX PANHANDLE. WITH TIME ADDITIONAL STORMS MAY EVOLVE INTO
THE CNTRL TX PANHANDLE...THEN SPREAD INTO NWRN OK IN LINE WITH
EARLIER THINKING. AT THIS TIME IT APPEARS HAIL IS THE GREATEST
CONCERN.