Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 291913
SWOMCD
SPC MCD 291912
ALZ000-FLZ000-MSZ000-292115-

MESOSCALE DISCUSSION 1570
NWS STORM PREDICTION CENTER NORMAN OK
0212 PM CDT WED JUL 29 2015

AREAS AFFECTED...PORTIONS OF ERN MS...MUCH OF AL...AND THE WRN FL
PANHANDLE

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 291912Z - 292115Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...CLUSTERS OF THUNDERSTORMS WILL REMAIN CAPABLE OF PRODUCING
STRONG/GUSTY WINDS FOR THE NEXT SEVERAL HOURS. WW ISSUANCE IS
UNLIKELY AT THIS TIME.

DISCUSSION...A SUBTLE VORTICITY MAXIMUM EVIDENT ON WATER VAPOR
SATELLITE IMAGERY AND ANALYZED BY THE RAP OVER NRN AL/NERN MS AS OF
19Z WILL CONTINUE MOVING SWD THROUGH THE REMAINDER OF THE AFTERNOON.
A VERY MOIST LOW-LEVEL AIRMASS IS PRESENT OVER THE MCD AREA...WITH
SFC DEWPOINTS IN THE LOWER TO MID 70S. POCKETS OF HEATING HAVE
GENERALLY ALLOWED THE ATMOSPHERE TO DESTABILIZE...WITH RAP
MESOANALYSIS ESTIMATING MLCAPE OF 2000-2500 J/KG ACROSS THE AREA.
THIS INSTABILITY ESTIMATE AGREES WELL WITH ADJUSTING THE 12Z
SOUNDING FROM BMX FOR CURRENT SFC OBSERVATIONS. SOMEWHAT ENHANCED
NLY LOW TO MID-LEVEL FLOW OF 20-30 KT IN THE 2-6 KM LAYER IS
ASSOCIATED WITH THE VORTICITY MAXIMUM...AND IS GENERALLY PRESENT
ACROSS NRN PORTIONS OF THE MCD AREA PER VARIOUS RADAR VWPS.

TWO VERY LOOSELY ORGANIZED CLUSTERS OF THUNDERSTORMS ARE ONGOING AS
OF 19Z...ONE OVER NERN MS TO E-CNTRL AL...AND ANOTHER OVER W-CNTRL
TO SERN AL. THESE CLUSTERS ARE MOVING GENERALLY SWD WITH THE MEAN
ATMOSPHERIC FLOW. CURRENT EXPECTATIONS ARE FOR BOTH CONVECTIVE AREAS
TO REMAIN MOSTLY DISORGANIZED GIVEN WEAK BULK SHEAR AND POOR
MID-LEVEL LAPSE RATES. HOWEVER...THE ENHANCED NLY FLOW MAY ENCOURAGE
SOME CONVECTIVE DOWNDRAFTS TO BECOME STRONG/GUSTY AT TIMES...WITH AN
OCCASIONAL TREE DOWN THREAT. THUNDERSTORMS SHOULD RAPIDLY WEAKEN BY
EARLY EVENING WITH THE LOSS OF DAYTIME HEATING.

..GLEASON/GOSS.. 07/29/2015

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

ATTN...WFO...TAE...BMX...HUN...MOB...MEG...JAN...LIX...

LAT...LON   34438932 34598879 34548792 34328691 33948556 33708546
            32078520 30718567 30388616 30368700 30288775 30568868
            31208949 33268947 34438932



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