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000
ACUS01 KWNS 170037
SWODY1
SPC AC 170035

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0735 PM CDT THU MAY 16 2013

VALID 170100Z - 171200Z

...THERE IS A SLGT RISK OF SVR TSTMS FOR THE ARKLAMISS REGION...

...SYNOPSIS...
WATER VAPOR IMAGERY SHOWS SEVERAL MID LEVEL VORTICITY MAXIMA OVER
THE CNTRL AND ERN U.S. AND THESE FEATURES WILL CONTINUE TO MOVE EWD
AND PROVIDE A FOCUS FOR SHOWERS/STORMS THROUGH FRIDAY MORNING.
EARLY EVENING SUBJECTIVE MESOANALYSIS SHOWS SEVERAL CONVECTIVELY
MODULATED BOUNDARIES 1) OUTFLOW/DIFFERENTIAL HEATING ZONE OVER THE
ARKLATEX 2) NWRN KS COLD POOL INTERSECTION AND EFFECTIVE FRONTAL
ZONE OVER CNTRL NE.  OTHER LARGER SCALE LOW LEVEL FEATURES INCLUDE A
FRONT EXTENDING EWD FROM A SURFACE LOW INVOF THE BLACK HILLS THAT
SHOULD REMAIN LARGELY STATIONARY THROUGH THE OVERNIGHT WHILE A
DRYLINE EXTENDS SWD THROUGH THE HIGH PLAINS INTO S-CNTRL TX.

...ARKLAMISS REGION...
MID LEVEL LOW OVER AR WILL MOVE SLOWLY EWD ACROSS NRN AR AND REACH
THE MS RIVER BY EARLY MORNING BUT PROVIDE AN IMPETUS FOR FORCED
ASCENT ACROSS THE LOWER MS VALLEY.  WHEN MODIFIED FOR CURRENT AND
EXPECTED SURFACE CONDITIONS OVER THE AREA...THE 00Z/17 SHV RAOB IS
MORE THAN ADEQUATELY MOIST AND MODERATELY UNSTABLE.  ALTHOUGH THE
LATEST NUMERICAL GUIDANCE ONLY DEPICTS MODEST LOW LEVEL FLOW /30 KT
AT H85/...CURRENT OBSERVATIONS FROM KPOE AND KSHV VWP/S DEPICT A
RIBBON OF 30-50 KT 1-2 KM FLOW ENHANCING LOW LEVEL SHEAR.  THIS MAY
CONTINUE TO SUPPORT AT LEAST THE RISK FOR LOW LEVEL MESOCYCLONE
DEVELOPMENT INTO THE NIGHTTIME HOURS AND AN ASSOCIATED THREAT FOR
LOCALLY DMGG WINDS AND POSSIBLY A TORNADO.

...PORTIONS OF THE CNTRL PLAINS THIS EVENING...
DESPITE A WELL-ESTABLISHED COLD POOL OVER NWRN KS...A GRADUAL
DECOUPLING OF THE BOUNDARY LAYER THIS EVENING WILL ACT TO LESSEN
INSTABILITY AND THE DAMAGING WIND/LARGE HAIL THREAT WITH TIME.
FARTHER N OVER CNTRL NE...A MATURE MCV EVIDENT ON RADAR MOSAIC...MAY
ACT TO SUSTAIN AT LEAST A THREAT FOR AN ISOLD STRONG TO SEVERE STORM
THE NEXT FEW HOURS S OF A WEST-EAST ORIENTED OUTFLOW LOCATED OVER
E-CNTRL NE.  OTHERWISE...GRADUAL WANING IN INSTABILITY IN
SURROUNDING AREAS MAY FOSTER A WIND GUST/LARGE HAIL REPORT BEFORE
THIS ACTIVITY WEAKENS THIS EVENING.

..SMITH.. 05/17/2013