MESO: Mesoscale Discussion 0857

ACUS11 KWNS 211800
SWOMCD
SPC MCD 211759
OKZ000-TXZ000-COZ000-NMZ000-211930-

MESOSCALE DISCUSSION 0857
NWS STORM PREDICTION CENTER NORMAN OK
1259 PM CDT MON MAY 21 2012

AREAS AFFECTED...EXTREME SERN CO...NERN/E-CNTRL NM...WRN TX/OK
PANHANDLES

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 211759Z - 211930Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...ISOLATED TO SCATTERED THUNDERSTORMS...INCLUDING A FEW
SUPERCELLS...ARE EXPECTED TO DEVELOP THIS AFTERNOON ACROSS PORTIONS
OF EXTREME SERN CO...NERN/E-CNTRL NM AND THE WRN TX/OK PANHANDLES.
LARGE HAIL AND DAMAGING WIND GUSTS WILL BE THE PRIMARY SVR WEATHER
THREATS. WW IS LIKELY.

DISCUSSION...VISIBLE SATELLITE IMAGERY SHOWS MORNING THUNDERSTORM
ACTIVITY HAS CLEARED THE TX PANHANDLE. IN ITS WAKE...SURFACE COLD
POOL IS EVIDENT IN 17Z SURFACE OBSERVATIONS /TEMPERATURES NEAR 70F
OVER THE PANHANDLE/...WITH AN OUTFLOW BOUNDARY ORIENTED ROUGHLY N-S
OVER FAR E-CNTRL NM. BACKED SURFACE WINDS ACROSS THE COOL SIDE OF
THE OUTFLOW BOUNDARY VEER TO SLY OVER NERN NM AND SERN CO...WHICH IS
AIDING IN MAINTAINING A RELATIVELY MOIST AIRMASS OVER THE SRN HIGH
PLAINS /DEWPOINTS IN THE MID 50S...MIXING RATIO VALUES FROM 9-11 G
PER KG/. GIVEN THE COMBINATION OF 700-500 MB LAPSE RATES FROM 7-8
C/KM AND MOIST/WARMING BOUNDARY LAYER...MLCAPE VALUES NEAR 1500 J/KG
ARE DEVELOPING ACROSS E-CNTRL INTO NERN NM. IN ADDITION...SURFACE
HEATING OVER THE SRN ROCKIES AND RATON MESA IS LEADING TO RAPIDLY
STEEPENING LOW-LEVEL LAPSE RATES...WHICH IS ENHANCING CUMULUS
GROWTH.

GIVEN THESE TRENDS...THUNDERSTORM INITIATION IS EXPECTED TO TAKE
PLACE DURING THE NEXT FEW HRS OVER THE HIGHER TERRAIN...AND THEN
SPREAD SEWD AS THE PLAINS CONTINUE TO DESTABILIZE. BOTH TCU PROFILER
DATA AND RAP FORECAST SOUNDINGS SHOW LOW-LEVEL S-SELYS VEERING TO
20-30 KT NWLY FLOW IN THE MIDLEVELS...WHICH WILL YIELD SUFFICIENT
VERTICAL WIND SHEAR FOR SUPERCELLS. THOUGH AN ISOLATED TORNADO WILL
BE POSSIBLE...PRIMARY SVR WEATHER THREATS WILL BE LARGE HAIL
/POSSIBLY VERY LARGE/ AND DAMAGING WIND GUSTS.

..GARNER/WEISS.. 05/21/2012

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

ATTN...WFO...LUB...AMA...PUB...ABQ...

LAT...LON 37490274 36960203 35670182 34110231 33930402 35100540
36800495 37470392 37490274

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.