SPC MD 1171

MD 1171 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR NERN CO


MESOSCALE DISCUSSION 1171
NWS STORM PREDICTION CENTER NORMAN OK
0111 PM CDT SAT JUN 22 2013

AREAS AFFECTED...NERN CO

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 221811Z - 222015Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...WIDELY SCATTERED STORMS ARE EXPECTED TO DEVELOP OVER THE
MOUNTAINS OF NCTRL CO AND SUBSEQUENTLY MOVE INTO THE HIGH PLAINS OF
NERN CO THIS AFTERNOON. ISOLATED LARGE HAIL AND DAMAGING WIND WILL
BE THE MAIN THREATS. TRENDS WILL BE MONITORED FOR A POSSIBLE WW
ISSUANCE BY 20Z.

DISCUSSION...EARLY THIS AFTERNOON SATELLITE IMAGERY SHOWS CUMULUS
DEVELOPMENT OVER THE HIGHER TERRAIN OF NCNTRL CO. THE CIRCULATION
AROUND A SFC LOW OVER NWRN KS IS RESULTING IN ENELY LOW-LEVEL WINDS
WHICH WILL MAINTAIN INFLUX OF LOW-MID 50S DEWPOINTS OVER THE HIGH
PLAINS OF NERN CO AND A MODEST UPSLOPE COMPONENT. STRONG DIABATIC
WARMING IS DESTABILIZING THE SFC LAYER...AND LATEST OBJECTIVE
ANALYSIS SHOWS MLCAPE FROM 1000-1500 J/KG. BASED ON MODIFIED 12Z
RAOBS AND POINT FORECAST SOUNDINGS...TEMPERATURES IN THE MID-UPPER
80 F ARE NEEDED TO SUSTAIN ROBUST THUNDERSTORMS EAST OF THE HIGHER
TERRAIN. THIS SUGGESTS ANOTHER 1.5 - 2 HOURS OF INSOLATION IS NEEDED
OVER THE NERN CO HIGH PLAINS BEFORE STORMS BEGIN TO POSE A SEVERE
THREAT. THE 30-35 KT SWLY FLOW AT 500 MB ABOVE LIGHT ELY NEAR SFC
WINDS IS CONTRIBUTING TO 40-45 KT EFFECTIVE SHEAR THAT WILL FAVOR A
FEW SUPERCELLS ONCE STORMS DEVELOP AND ROOT INTO THE BOUNDARY LAYER.

..DIAL/KERR.. 06/22/2013

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

ATTN...WFO...BOU...

LAT...LON   39840292 39430398 39680483 40670525 40960451 40830285
            39840292

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