Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS01 KWNS 300535
SWODY1
SPC AC 300534

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1234 AM CDT SUN AUG 30 2015

VALID 301200Z - 311200Z

...THERE IS A MRGL RISK OF SVR TSTMS PARTS OF MT...

...SUMMARY...
ISOLATED SEVERE STORMS WITH WIND AND HAIL MAY DEVELOP ACROSS PARTS
OF MONTANA THIS AFTERNOON INTO MID-EVENING.

...MT...
A PROGRESSIVE SHORTWAVE TROUGH NEAR THE WA COAST SHOULD DAMPEN AS IT
REACHES THE NRN GREAT PLAINS INTERNATIONAL BORDER AREA EARLY MON.
EVEN WITH DAMPENING...A BROAD BELT OF 500-MB SWLYS AOA 50 KT IS
EXPECTED TO BE CENTERED ACROSS THE NRN ROCKIES AND ADJACENT HIGH
PLAINS THIS AFTERNOON. WITH VERY STRONG UPPER-LEVEL
FLOW...HODOGRAPHS WILL BECOME RATHER ELONGATED FAVORING A
CONDITIONAL RISK FOR SPLITTING SUPERCELL STRUCTURES.

WITH AN INITIAL FRONTAL SURGE THIS MORNING OVER THE NRN HIGH
PLAINS...AFTERNOON TEMPERATURES ARE EXPECTED TO BE AROUND 10-15 DEG
F COOLER COMPARED TO SAT ACROSS CNTRL MT. NEVERTHELESS...INVERTED-V
THERMODYNAMIC PROFILES SHOULD REMAIN COMMON BUT BUOYANCY WILL LIKELY
BE MEAGER WITH MLCAPE ONLY AROUND 250-500 J/KG. FAVORABLE TIMING OF
MID-LEVEL DCVA WITH RESPECT TO THE DIURNAL HEATING CYCLE SHOULD
FOSTER ISOLATED TSTMS FORMING OVER THE W-CNTRL MT MTNS IN THE EARLY
AFTERNOON. THIS ACTIVITY SHOULD DEVELOP/SPREAD E THROUGH THE
AFTERNOON WITH A RISK FOR ISOLATED SEVERE WIND GUSTS AND MARGINALLY
SEVERE HAIL...BEFORE LIKELY DIMINISHING ACROSS PARTS OF ERN MT JUST
AFTER SUNSET.

...SOUTHEAST STATES...
SCATTERED TSTMS SHOULD BE ONGOING ALONG THE S ATLANTIC COAST AT 12Z
DOWNSTREAM OF A PERSISTENT UPPER-LEVEL CIRCULATION CENTERED NEAR
MOBILE BAY. CONVECTION SHOULD DEVELOP INLAND AND BECOME WIDESPREAD
THROUGH THE DAY AS THE CIRCULATION GRADUALLY SHIFTS NE TOWARDS NRN
GA. THE BEST POTENTIAL FOR WEAKLY ORGANIZED CONVECTION APPEARS TO BE
OVER PARTS OF CNTRL/SRN GA WITHIN A BELT OF ENHANCED MID/UPPER-LEVEL
SLYS. BUT GIVEN LARGE UNCERTAINTY OVER WHETHER SUFFICIENT DIABATIC
HEATING CAN OCCUR TO SUPPORT A RISK FOR LOCALLY DAMAGING
WINDS...WILL DEFER TO LATER OUTLOOKS FOR POSSIBLE MARGINAL RISK
DELINEATION.

..GRAMS/PICCA.. 08/30/2015



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