DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 071300
SWODY1
SPC AC 071258

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0758 AM CDT SUN OCT 07 2012

VALID 071300Z - 081200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN NC/SC...

...SYNOPSIS...
BROAD CYCLONIC FLOW WILL PREVAIL OVER MOST OF THE CNTRL AND ERN U.S.
THROUGH MON...DOWNSTREAM FROM E PACIFIC REX BLOCK. TWO NOTABLE
SHORTWAVE IMPULSES ARE APPARENT IN THE CYCLONIC FLOW...ONE NOW OVER
IL AND THE OTHER OVER CO. THE IL DISTURBANCE SHOULD MOVE ENE INTO
PA/WRN MD BY EVE...AND NE INTO NEW BRUNSWICK BY 12Z MON...WHILE THE
OTHER TRACKS SE INTO WRN OK LATER TODAY...AND INTO WRN TN/NRN MS
EARLY MON.

AT THE SFC...PATTERN WILL BE DOMINATED BY EXPANSIVE BUT GRADUALLY
WEAKENING SFC RIDGE. COLD FRONT MARKING THE LEADING EDGE OF THE
RIDGE HAS CLEARED ALL BUT THE SRN NC AND SC CST THIS MORNING. THE
FRONT SHOULD PROGRESS SLOWLY E/SE THROUGH THE DAY...WITH ASSOCIATED
SFC WAVE NOW OVER THE SC PIEDMONT TRACKING EWD ALONG BOUNDARY INTO
SRN NC.

...ERN/SRN CAROLINAS THROUGH LATE AFTN...
BAND OF ENHANCED WSWLY MID-LVL FLOW /WITH SPEEDS AOA 40 KTS AT 700
MB/ ATTENDANT TO IL SHORTWAVE IMPULSE WILL GLANCE NRN AND ERN PARTS
OF THE CAROLINAS TODAY AS THE DISTURBANCE CONTINUES ENEWD. FAIRLY
RICH MOISTURE WILL REMAIN IN PLACE ACROSS REGION...ESPECIALLY ALONG
THE NC/SC...BUT ALSO FARTHER W ATOP SHALLOW...POST COLD-FRONTAL AIR
MASS OVER THE CAROLINA PIEDMONT.

GIVEN MOISTURE AVAILABILITY AND PRESENCE OF RELATIVELY STEEP MID LVL
LAPSE RATES...SFC HEATING ALONG AND AHEAD OF COLD FRONT OVER THE SC
AND SRN NC CSTL PLN SHOULD YIELD MODERATE INSTABILITY BY AFTN...WITH
1500-2000 J/KG MLCAPE. COUPLED WITH STRENGTH OF UNIDIRECTIONAL WSWLY
MID/UPR LVL FLOW...POTENTIAL WILL EXIST FOR A FEW SFC-BASED STORMS
WITH LOCALLY DMGG WIND AND POSSIBLY MARGINALLY SVR HAIL. STORMS ALSO
COULD FORM ALONG THE SEA BREEZE FRONT. WEAK LARGE SCALE FORCING FOR
ASCENT AND MODEST LOW LVL CONVERGENCE SHOULD...HOWEVER...LIMIT
OVERALL SVR THREAT.

IN THE MEANTIME...POTENTIAL FOR SUSTAINED SVR ACTIVITY WITH SMALL
ELEVATED CONVECTIVE SYSTEM NOW TRACKING E ACROSS S CNTRL NC APPEARS
MINIMAL GIVEN STABLE NATURE OF BOUNDARY LAYER AND WEAKNESS OF BOTH
LARGE SCALE FORCING FOR ASCENT AND ELEVATED CONFLUENCE.

..CORFIDI/HURLBUT.. 10/07/2012

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.