DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 151954
SWODY1
SPC AC 151952

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0152 PM CST SAT DEC 15 2012

VALID 152000Z - 161200Z

...NO SVR TSTM AREAS FORECAST...

...E TX TO LWR MS/TN VLYS TODAY THROUGH EARLY SUN...
NO CHANGES NEEDED TO PRIOR OUTLOOK...SEE DISCUSSION BELOW. LATEST
SHORT-TERM GUIDANCE STILL SUGGESTS AN INCREASE IN TSTM
COVERAGE/VIGOR WILL OCCUR LATE TONIGHT/EARLY SUNDAY FOR AREAS
INCLUDING E/SE TX INTO LA/SOUTHERN AR AND NORTHERN MS.

..GUYER.. 12/15/2012

.PREV DISCUSSION... /ISSUED 1028 AM CST SAT DEC 15 2012/

...SYNOPSIS...
FAST SW TO WSW FLOW WILL PREVAIL FROM THE S CNTRL STATES INTO THE
EAST THIS PERIOD...ON NRN FRINGE OF PERSISTENT...ELONGATED RIDGE
OVER THE GULF OF MEXICO/FL. WITHIN THIS FLOW...LEAD SHORTWAVE
IMPULSE NOW IN IA/IL EXPECTED TO DEAMPLIFY AS IT CONTINUES NE TO LK
MI THIS EVE...AND TO LK HURON EARLY SUN. ELSEWHERE...A PAIR OF UPR
DISTURBANCES IN BROAD...LARGER-SCALE TROUGH OVER THE GRT BASIN WILL
REACH THE FOUR CORNERS REGION/NW MEXICO THIS EVE...AND THE OK/TX
PANHANDLE/W TX BY 12Z SUN...WITH LITTLE CHANGE IN INTENSITY.

AT THE SFC...COLD FRONT ASSOCIATED WITH IA/IL TROUGH SHOULD WEAKEN
AND BECOME QSTNRY FROM THE LWR OH VLY TO E TX BY THE END OF THE
PERIOD AS SFC LOW NOW IN IA CONTINUES NE TO NEAR GREEN BAY. THE SWRN
END OF THE FRONT MAY EDGE A BIT NWD ACROSS E TX EARLY SUN IN
RESPONSE TO UPR SYSTEMS APPROACHING FROM THE W.

...E TX TO LWR MS/TN VLYS TODAY THROUGH EARLY SUN...
SCTD SHOWERS AND OCCASIONAL TSTMS WILL PERSIST INVOF WEAKENING
FRONTAL ZONE TODAY/TNGT FROM THE LWR TN VLY SW INTO PARTS OF E TX.
ABSENCE OF STRONG/DEEP FORCING FOR ASCENT AND WEAK TO MODEST MID LVL
LAPSE RATES SHOULD LIMIT CONVECTIVE COVERAGE/STRENGTH...DESPITE
PRESENCE OF SEASONABLY RICH MOISTURE /PW TO 1.25 INCHES/ NEAR
BOUNDARY.

SOME INCREASE IN STORM COVERAGE/STRENGTH MAY OCCUR LATE TNGT THROUGH
EARLY SUN...ESPECIALLY FROM E/SE TX ENE INTO NRN LA/SRN AR AND NRN
MS AS WAA AND MOISTURE TRANSPORT INCREASE DOWNSTREAM FROM
APPROACHING UPR DISTURBANCES. MOST OF THIS ACTIVITY SHOULD BE
SLIGHTLY ELEVATED...OCCURRING ALONG AND N OF FRONT. WHILE MID-LVL
LAPSE RATES LIKELY WILL REMAIN WEAK...QUALITY OF MOISTURE INFLOW /PW
INCREASING TO AOA 1.50 INCHES/ AND 50 KT CLOUD-LAYER SHEAR SUGGEST
THE POTENTIAL FOR A FEW SUSTAINED UPDRAFTS/LOOSELY-ORGANIZED
CLUSTERS.

WITH THE UPR IMPULSES AND ASSOCIATED STRONGER ASCENT LIKELY TO
REMAIN WELL WEST OF PRE-FRONTAL WARM SECTOR THROUGH THE PERIOD...AND
WITH THE DISTURBANCES NOT EXPECTED TO AMPLIFY...CONFIDENCE REMAINS
LOW THAT A SUSTAINED SVR WEATHER THREAT WILL OCCUR...ESPECIALLY
GIVEN TIME OF DAY/LACK OF SFC HEATING. NEVERTHELESS...STRENGTH OF
MEAN FLOW AND HIGH PW VALUES TOGETHER POSE A SUFFICIENT RISK FOR
ISOLD RAIN-LOADING ENHANCED GUSTS TO MAINTAIN A LOW PROBABILISTIC
FORECAST FOR DMGG WINDS ACROSS THE REGION.

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