Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS02 KWNS 021139
SWODY2
SPC AC 021137

DAY 2 CONVECTIVE OUTLOOK CORR 1
NWS STORM PREDICTION CENTER NORMAN OK
0637 AM CDT SUN AUG 02 2015

VALID 031200Z - 041200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NERN STATES INTO A
PORTION OF THE OH VALLEY...

...THERE IS A MRGL RISK OF SVR TSTMS FROM THE NERN STATES INTO THE
OH VALLEY...

...THERE IS A MRGL RISK OF SVR TSTMS FROM THE CNTRL PLAINS INTO THE
MIDDLE MS VALLEY...

CORRECTED FOR PROBABILITY CONTOURS

...SUMMARY...
A FEW STRONG TO SEVERE STORMS MAY OCCUR OVER THE NORTHEAST STATES
AND A PORTION OF THE CENTRAL PLAINS INTO THE MIDDLE MISSISSIPPI
VALLEY.

...SYNOPSIS...

EMBEDDED WITHIN BASE OF AN UPPER LOW CIRCULATION CENTERED OVER SERN
CANADA...A SHORTWAVE TROUGH AND ATTENDANT UPPER JET WILL CONTINUE
THROUGH THE GREAT LAKES REGION AND INTO THE NERN STATES ACCOMPANIED
BY A COLD FRONT. TRAILING PORTIONS OF THIS BOUNDARY WILL STALL OVER
THE CNTRL PLAINS AREA.

...NERN STATES INTO THE OH VALLEY...

MODIFIED CP AIR WITH UPPER 50S TO MID 60S F DEWPOINTS WILL ADVECT
THROUGH PRE-FRONTAL WARM SECTOR AND CONTRIBUTE TO MODEST 500-1500
J/KG MLCAPE AS THE BOUNDARY LAYER WARMS. THE STRONGER INSTABILITY
WILL RESIDE OVER THE OH VALLEY WHERE RICHER LOW-LEVEL MOISTURE WILL
EXIST. A FEW THUNDERSTORMS MAY BE ONGOING ALONG AND AHEAD OF COLD
FRONT WITHIN WARM CONVEYOR BELT OVER A PORTION OF THE NERN STATES.
ADDITIONAL STORMS WILL DEVELOP ALONG AND JUST AHEAD OF THE FRONT AS
THE ATMOSPHERE DESTABILIZES DURING THE AFTERNOON. ACTIVITY WILL BE
EMBEDDED WITHIN A BELT OF STRONGER DEEP-LAYER WINDS WITHIN THE UPPER
LOW CIRCULATION. THE STRONGER STORMS WILL BECOME CAPABLE OF
PRODUCING MAINLY DAMAGING WIND.

...CNTRL PLAINS INTO THE MID MS VALLEY...

MODERATE INSTABILITY IS EXPECTED IN VICINITY OF STALLED FRONT FROM
THE CNTRL PLAINS INTO THE MID MS VALLEY...MOST LIKELY FROM NRN KS TO
SRN NEB AND NRN MO. THIS BOUNDARY WILL REMAIN SOUTH OF STRONGER
WINDS ALOFT...BUT SUFFICIENT VEERING WILL EXIST TO SUPPORT 25-35 KT
EFFECTIVE SHEAR. THUNDERSTORM INITIATION ALONG THE FRONT DURING THE
AFTERNOON REMAINS UNCERTAIN DUE TO WEAK FORCING AND PRESENCE OF A
CAP. GREATER CONFIDENCE EXISTS THAT STORMS WILL DEVELOP AND BECOME
MORE WIDESPREAD MONDAY EVENING AND OVERNIGHT AS THE LLJ STRENGTHENS
AND AUGMENTS CONVERGENCE AND ISENTROPIC ASCENT IN VICINITY OF THE
FRONT. THE STRONGER STORMS MIGHT BECOME CAPABLE OF PRODUCING A FEW
INSTANCES OF STRONG TO DAMAGING WIND AND HAIL.

..DIAL.. 08/02/2015



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