MESO: Mesoscale Discussion 1095

ACUS11 KWNS 161805
SWOMCD
SPC MCD 161805
NEZ000-SDZ000-COZ000-161930-

MESOSCALE DISCUSSION 1095
NWS STORM PREDICTION CENTER NORMAN OK
0105 PM CDT SUN JUN 16 2013

AREAS AFFECTED...SWRN SD...WRN NEB

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 161805Z - 161930Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...THUNDERSTORMS ARE FORECAST TO INCREASE IN COVERAGE AND
INTENSIFY OVER SWRN SD AND WRN NEB THIS AFTERNOON. LARGE HAIL AND
DAMAGING WIND GUSTS WILL BE POSSIBLE. WW WILL BE ISSUED DURING THE
NEXT ONE TO TWO HOURS.

DISCUSSION...MAINLY ELEVATED THUNDERSTORMS HAVE BEEN OCCURRING OVER
SWRN SD INTO PORTIONS OF WRN/CNTRL NEB DURING THE MORNING. MOST OF
THIS ACTIVITY IS BEGINNING TO DRIFT EWD AND WEAKEN AS IT ENCOUNTERS
A DIVERGENT LOW-LEVEL FLOW REGIME. HOWEVER...OUTFLOW HAS BEEN LAID
OUT IN A NNW-SSE ORIENTATION OVER WRN NEB...WITH ANOTHER AREA OF
OUTFLOW SURGING SWD OVER SWRN SD. IN ADDITION...SURFACE WINDS HAVE
VEERED TO SWLY OVER THE NEB PANHANDLE...WHICH IS AIDING IN AN
ENHANCED ZONE OF CONVERGENCE OVER ALONG AND W OF THE OUTFLOW.
MODIFYING THE 12Z LBF RAOB FOR CURRENT TEMPERATURES IN THE UPPER
70S/LOW 80S...AND DEWPOINTS IN THE MID TO UPPER 50S YIELDS MLCINH
NEAR 0 J/KG AND MLCAPE VALUES APPROACHING 2500-3000 J/KG.
THUS...ENVIRONMENT APPEARS FAVORABLE FOR SURFACE BASED THUNDERSTORM
DEVELOPMENT.

TWO SCENARIOS APPEAR POSSIBLE THIS AFTERNOON. STORMS COULD EITHER
FORM ALONG THE OUTFLOW SURGING S OVER SWRN SD INTO NWRN NEB...AND
THEN CONTINUE PROPAGATING SWD ACROSS WRN NEB...OR...STORMS COULD
FORM WITHIN A PLUME OF ASCENT/ELEVATED MOISTURE SPREADING NEWD OUT
OF CO WITH THUNDERSTORM INTENSIFICATION TAKING PLACE AS GREATER
MOISTURE/CAPE IS ENCOUNTERED OVER WRN NEB. ONCE THUNDERSTORMS DO
DEVELOP...LOW-LEVEL SELYS VEERING TO WLY IN THE MID/UPPER LEVELS
/WHERE SPEEDS EXCEED 30+ KT/ COMBINED WITH STEEP MIDLEVEL LAPSE
RATES AND MODERATE TO STRONG BUOYANCY WILL FAVOR SUPERCELLS POSING A
LARGE HAIL/DAMAGING WIND THREAT...AND PERHAPS AN ISOLATED TORNADO.
ACTIVITY WILL EVENTUALLY MERGE AND GROW UPSCALE INTO AN MCS AS IT
MOVES SEWD.

..GARNER/THOMPSON.. 06/16/2013

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

ATTN...WFO...GID...LBF...UNR...GLD...BOU...CYS...

LAT...LON 41529918 40639879 40059943 40000118 40600227 41760341
42920361 43630219 43130086 41529918

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.