SPC MD 1702

MD 1702 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF ERN CO…WRN KS…SWRN NEB…SERN WY

MESOSCALE DISCUSSION 1702
NWS STORM PREDICTION CENTER NORMAN OK
0335 PM CDT MON AUG 12 2013

AREAS AFFECTED...PORTIONS OF ERN CO...WRN KS...SWRN NEB...SERN WY

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 122035Z - 122300Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...AN ISOLATED SVR THREAT MAY DEVELOP THIS AFTERNOON.

DISCUSSION...AN ELY COMPONENT OF THE LOW-LEVEL FLOW CONTINUES TO
TRANSPORT MODESTLY RICH MOISTURE INTO THE HIGH PLAINS...WITH SFC
DEWPOINTS IN THE LOWER/MIDDLE 50S IN MANY AREAS JUST E OF THE ROCKY
MOUNTAIN FRONT RANGE. HIGHER DEWPOINTS -- INTO THE LOWER 60S -- ARE
FOUND OVER THE LOWER ELEVATIONS. UPSLOPE FLOW/TERRAIN-DRIVEN
CIRCULATIONS CONTINUE SUPPORTING SCATTERED THUNDERSTORMS OVER THE CO
FRONT RANGE...WITH ADDITIONAL ACTIVITY FARTHER N INTO SERN WY AND
INVOF A FRONT EXTENDING SEWD FROM FAR SERN WY INTO NERN CO AND NWRN
KS.

VISIBLE SATELLITE DATA INDICATE FAIRLY WELL-STRUCTURED ANVILS
EMANATING FROM THIS CONVECTION AND EXTENDING DOWNSHEAR/EWD...IN
RESPONSE TO MODERATE HIGH-LEVEL FLOW/CONVECTIVE VENTILATION.
MODERATE INSTABILITY MAY SUPPORT A FEW VIGOROUS UPDRAFTS/DOWNDRAFTS
WITH SVR HAIL/WIND OCCURRING ON SPORADIC BASIS...AS CONVECTION IS
FORECAST TO HAVE A TENDENCY OF SPREADING ACROSS THE LOWER ELEVATIONS
INTO LATE AFTERNOON/THIS EVENING. HOWEVER...LOW/MID-LEVEL FLOW AOB 6
KM AGL IS RELATIVELY MODEST -- GENERALLY 25 KT OR LESS -- PER AREA
WIND PROFILER DATA...AND THIS MAY SERVE AS A MITIGATING FACTOR FOR
MORE ORGANIZED CONVECTION AND LESSEN THE OVERALL SVR THREAT.
ALSO...THE LACK OF STRONGER DEEP-LAYER FORCING FOR ASCENT MAY REDUCE
THE COVERAGE/MAGNITUDE OF ANY SVR POTENTIAL.

..COHEN/KERR.. 08/12/2013

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

ATTN...WFO...LBF...DDC...GLD...PUB...BOU...CYS...

LAT...LON   41450556 41700333 40990139 40320095 38170085 37100161
            37250408 37980505 39500544 41450556

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