SPC MD 1702

MD 1702 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR FAR NERN OK/SERN KS…SRN/CNTRL MO…FAR NRN AR


MESOSCALE DISCUSSION 1702
NWS STORM PREDICTION CENTER NORMAN OK
0520 PM CDT SAT AUG 04 2012

AREAS AFFECTED...FAR NERN OK/SERN KS...SRN/CNTRL MO...FAR NRN AR

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 042220Z - 042345Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...SCATTERED THUNDERSTORMS ARE FORECAST TO DEVELOP THIS
EVENING ALONG AND AHEAD OF A COLD FRONT ACROSS PORTIONS OF FAR NERN
OK/SERN KS...SRN/CNTRL MO...AND FAR NRN AR. THREAT FOR DAMAGING
WINDS AND LARGE HAIL WILL EXIST...TRENDS WILL BE MONITORED FOR A
POSSIBLE WW.

DISCUSSION...MESOANALYSIS AT 22Z SHOWS A COLD FRONT EXTENDING SWWD
FROM CNTRL IL INTO SWRN MO AND NRN OK. TEMPERATURES HAVE WARMED TO
NEAR 110F ALONG THE OK PORTION OF THE FRONT...AND HAVE AIDED IN THE
DEVELOPMENT OF STEEP LOW-LEVEL LAPSE RATES AND STRONG BOUNDARY LAYER
DESTABILIZATION...WHICH HAS FAVORED THE DEVELOPMENT OF A
THUNDERSTORM CLUSTER DURING THE LAST HR OR TWO. FARTHER E OVER SRN
MO AND FAR NRN AR...VISIBLE SATELLITE IMAGERY SHOWS DEEPENING
CUMULUS OCCURRING BETWEEN THE HOTTER/DRIER AIRMASS TO THE W AND
SLIGHTLY COOLER/MORE MOIST AIRMASS TO THE E. SHORT-TERM MODEL
GUIDANCE INDICATES THIS CUMULUS WILL EVOLVE INTO THUNDERSTORM
CLUSTERS...AND THEN SPREAD EWD TOWARD THE MS RIVER DURING THE NIGHT.
GIVEN SURFACE CONDITIONS CHARACTERIZED BY TEMPERATURES FROM
90-100F...DEWPOINTS IN THE 60S TO LOW 70S...AND STEEP MIDLEVEL LAPSE
RATES...ESTIMATES OF MLCAPE EXCEED 2000 J/KG OVER THE ERN HALF OF
SRN/CNTRL MO. THE LARGE BUOYANCY COMBINED WITH 0-6 KM BULK SHEAR
NEAR 30 KT WILL FAVOR STRONG TO SVR MULTICELL THUNDERSTORMS POSING A
THREAT FOR DAMAGING WINDS AND LARGE HAIL. MEANWHILE...STORMS
OCCURRING OVER FAR NERN OK/SERN KS AND SWRN MO MAY POSE A THREAT FOR
ISOLATED DAMAGING WIND GUSTS GIVEN THE PRESENCE OF A HOT AND MORE
STRONGLY MIXED BOUNDARY LAYER.

..GARNER/HART.. 08/04/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PAH...MEG...LSX...LZK...SGF...EAX...TSA...ICT...

LAT...LON   37009600 38729238 38869049 36909060 36129177 36129455
            36449607 37009600

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