SPC Day 1 Thunderstorm Outlook Issued 12Z 20031012


ZCZC SPCSWODY1 ALL
ACUS01 KWNS 120425
SPC AC 120425

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1125 PM CDT SAT OCT 11 2003

VALID 121200Z - 131200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 ENE CTB 30 NNW HLN
45 SW 3DU PUW 30 NNW YKM 10 WNW AST.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SSE CEW MAI VLD 30
SE JAX.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 SW TUS SOW 45 SSE
GNT 4CR 45 SSE CVS 35 ENE BGS 55 WNW LFK GLS.

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
IN MIDDLE-UPPER LEVELS...LARGELY ZONAL FLOW PATTERN TAKING SHAPE
ACROSS CONUS THROUGH PERIOD.  STRONG AND NEGATIVELY TILTED SHORTWAVE
TROUGH -- EVIDENT IN LATEST MOISTURE CHANNEL IMAGERY OVER MN/WI/IL
-- IS FCST TO MOVE RAPIDLY ENEWD ACROSS GREAT LAKES AND WEAKEN OVER
SERN ONT/WRN QUE.  ASSOCIATED SFC COLD FRONT WILL SWEEP EWD ACROSS
GREAT LAKES...MID ATLANTIC AND NEW ENGLAND AHEAD OF UPPER TROUGH. 
SRN PORTION OF SAME FRONT SHOULD WEAKEN AND DECELERATE OVER NWRN
GULF AMIDST NELY LOW LEVEL FLOW ON BOTH SIDES. SFC-BASED
INSTABILITY IS FCST TO BE SCANT TO NULL THROUGHOUT PERIOD.

--- GEN TSTM AREAS ---
CYCLONIC SHEAR/DEFORMATION ZONE ALOFT WILL EXTEND NEWD FROM
PERSISTENT NW MEX CUT-OFF LOW...COMBINING WITH ISENTROPIC ASCENT IN
LOW LEVELS TO MARGINALLY DESTABILIZE AIR MASS FROM RIO GRANDE VALLEY
TO SERN AZ...SUPPORTING GEN TSTM POTENTIAL.  MEANWHILE...WEAK LIFT
AND WEAK CINH INVOF LOW LEVEL FRONTAL/CONFLUENCE ZONE MAY SUPPORT
THUNDER OVER PORTIONS FL...HOWEVER CAPE AND SHEAR WILL BE TOO WEAK
FOR ORGANIZED SEVERE THREAT.  LOW-MIDLEVEL DESTABILIZATION AHEAD OF
PACIFIC NW TROUGH SHOULD SUPPORT MUCAPES GENERALLY AOB 200 J/KG AND
EPISODIC POTENTIAL FOR SHORT-LIVED TSTMS.

..EDWARDS.. 10/12/2003

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.

$$