DAY3SVR: Nws Storm Prediction Center Norman Ok

ACUS03 KWNS 180835
SWODY3
SPC AC 180834

DAY 3 CONVECTIVE OUTLOOK CORR 1
NWS STORM PREDICTION CENTER NORMAN OK
0234 AM CST TUE DEC 18 2012

VALID 201200Z - 211200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE GULF
COASTAL STATES...

CORRECTED FOR GENERAL THUNDER GRAPHIC

...SYNOPSIS...

GENERAL CONSENSUS AMONG NAM...GFS AND ECMWF IS THAT THE PROGRESSIVE
SHORTWAVE TROUGH WILL CONTINUE THROUGH ERN U.S. THURSDAY...WHILE
ATTENDANT SFC LOW DEEPENS AS IT LIFTS NEWD INTO THE GREAT LAKES IN
RESPONSE TO A JET MAX PIVOTING NEWD THROUGH ERN PERIPHERY OF THE
UPPER TROUGH. THE ATTENDANT COLD FRONT WILL SWEEP THROUGH THE OH
VALLEY AND SERN STATES BEFORE MOVING OFF THE ATLANTIC SEABOARD LATER
THURSDAY NIGHT.

...SERN STATES...

RELATIVELY FAST SPEED OF THE UPPER TROUGH IN WAKE OF RECENT GULF
FRONTAL INTRUSION WILL LIMIT DEGREE OF BOUNDARY LAYER MOISTURE
RECOVERY WITHIN PRE-FRONTAL WARM SECTOR. NEAR-SFC DEWPOINTS WILL
LIKELY RANGE FROM UPPER 60S NEAR THE GULF COAST TO AROUND 60 OVER
CNTRL PARTS OF THE SERN STATES. WEAK LAPSE RATES...WIDESPREAD LOW
CLOUDS AND LIMITED NWD ADVECTION OF RICHER LOW LEVEL MOISTURE WILL
SIGNIFICANTLY LIMIT INSTABILITY. A NARROW CORRIDOR OF WEAK
INSTABILITY WILL BE MAINTAINED WITHIN ZONE OF STRONGEST THETA-E
ADVECTION AND ASCENT JUST HEAD OF THE FRONT WITH MUCAPE AOB 400
J/KG.

A FORCED BAND OF LOW TOPPED CONVECTION WILL LIKELY ACCOMPANY THE
ZONE OF STRONG FRONTOGENETIC FORCING THROUGH THE SERN STATES. GIVEN
STRENGTH OF DEEP LAYER WIND PROFILES AND 50+ KT FLOW JUST ABOVE THE
SFC...SOME OF THE ACTIVITY MIGHT BECOME CAPABLE OF PRODUCING STRONG
TO DAMAGING WIND. THE WEAK THERMODYNAMIC ENVIRONMENT MAY ULTIMATELY
SERVE AS A LIMITING FACTOR...BUT FEEL AT LEAST A LOWER END /15%
PROBABILITY/ SLIGHT RISK AREA IS WARRANTED.

..DIAL.. 12/18/2012

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.