Severe Storm Outlook Narrative (AC)
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ACUS48 KWNS 201012
SWOD48
SPC AC 201010

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0410 AM CST SAT DEC 20 2014

VALID 231200Z - 281200Z

...DISCUSSION...
TUESDAY /DAY 4/...MODELS REMAIN IN GOOD AGREEMENT REGARDING
EVOLUTION OF A HIGH-AMPLITUDE UPPER TROUGH THAT IS FORECAST TO
ADVANCE THROUGH THE LOWER MS VALLEY INTO THE SERN STATES TUESDAY.

THOUGH SOME UNCERTAINTY REMAINS REGARDING OVERALL SEVERE THREAT ON
DAY 4 /PRIMARILY DUE TO EARLY ONSET OF PRECIPITATION/ FEEL AT LEAST
A 15% AREA APPEARS WARRANTED FROM THE LOWER MS VALLEY INTO THE GULF
COASTAL REGION INTO A PORTION OF THE FL PENINSULA. RICHER LOW-LEVEL
MOISTURE WITH LOW-MID 60S DEWPOINTS WILL ADVECT INLAND CONTRIBUTING
TO MODERATE INSTABILITY OVER THE LOWER MS VALLEY WHERE STEEPER LAPSE
RATES WILL EXIST. CAPE WILL REMAIN LIMITED FARTHER EAST ALONG THE
GULF COASTAL STATES DUE TO EARLY ONSET OF PRECIPITATION. STRONG
SHEAR ACCOMPANYING THE UPPER TROUGH WILL BE SUFFICIENT FOR SEVERE
STORMS. STORMS SHOULD INCREASE ALONG AND AHEAD OF THE FRONT AS WELL
AS ALONG THE GULF COASTAL REGION...A FEW OF WHICH COULD BE STRONG TO
SEVERE DURING THE DAY. OVERNIGHT...THE SEVERE THREAT MAY INCREASE
FARTHER EAST OVER THE FL PENINSULA AS MCS OVER THE GULF MOVES
INLAND.

WEDNESDAY /DAY 5/ SOME SEVERE POTENTIAL MAY LINGER INTO DAY 5 ALONG
THE ERN CAROLINAS AND POSSIBLY INTO THE FL PENINSULA AS UPPER TROUGH
TAKES ON A NEGATIVE TILT AND WIND FIELDS STRENGTHEN.
HOWEVER...PREDICTABILITY IS LOW DUE TO UNCERTAINTY REGARDING IMPACT
THAT WIDESPREAD EARLY PRECIPITATION MAY HAVE ON INSTABILITY OVER THE
CAROLINAS.

DAY 6-8...OVERALL SEVERE POTENTIAL WILL REMAIN GENERALLY LOW EXCEPT
POSSIBLY DAY 7.

..DIAL.. 12/20/2014



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