Friday, May 13, 2011

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 131624
SWODY1
SPC AC 131622

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1122 AM CDT FRI MAY 13 2011

VALID 131630Z - 141200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM MS/AL INTO THE MID MS
VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS ERN TN ACROSS CAROLINAS...

...MID MS VALLEY INTO MS AND AL...
UPPER LOW TRACKING SLOWLY EWD ACROSS SERN KS/SRN MO TO LWR OH VALLEY
BY 12Z SAT. SOMEWHAT DISORGANIZED SURFACE LOW OVER THE OH/MID MS
VALLEY THIS MORNING AS A COLD FRONT MOVES EWD FROM ITS CURRENT
POSITION SCENTRAL MO SWD THRU CENTRAL AR TO ACROSS MS RIVER BY LATER
THIS AFTERNOON.

CONSIDERABLE OVERNIGHT CONVECTION HAS BEEN MAKING ITS WAY EWD ACROSS
MID TN INTO NRN MS/AL THIS MORNING. CLEARING HAS OCCURRED IN THE
WAKE OF MORNING ACTIVITY ALONG MS RIVER VALLEY FROM SERN MO SWD INTO
NR LA WHICH WILL LEAD TO STRONG HEATING AND DESTABILIZATION THIS
AREA WHERE IT IS STILL QUITE MOIST.

WITH HEIGHT FALLS AND STRONGER MID/UPR FLOW SPREADING EWD ACROSS MID
MS/TN VALLEYS THIS AFTERNOON...STRONG/SEVERE THUNDERSTORMS ARE
EXPECTED TO REDEVELOP ALONG AND AHEAD OF THE COLD FRONT.

MLCAPES WILL CLIMB TO IN EXCESS OF 2000 J/KG PRIOR TO FROPA WHICH
COUPLED WITH 35-40 OF BRN SHEAR...SHOULD LEAD TO A FEW SEVERE
THUNDERSTORMS BY MID/LATE AFTERNOON. SUPERCELLS WILL BE POSSIBLE
EARLY IN THE CONVECTIVE INITIATION PERIOD...RAISING POTENTIAL FOR
BOTH LARGE HAIL AND ISOLATED TORNADOES.

STORMS ARE LIKELY TO GROW UPSCALE BY THIS EVENING INTO MORE OF A
LINEAR MODE WITH WIND DAMAGE POTENTIAL AS ACTIVITY MOVES EWD AHEAD
OF UPPER TROUGH ACROSS TN VALLEY SWD THRU MUCH OF MS/AL.

...ERN TN/CAROLINAS...

REF MCD 773

WHILE THE AREA WILL BE INFLUENCED BY A TRANSITORY UPPER RIDGE
TODAY...STRONG DAYTIME HEATING AND DEWPOINTS IN THE MID 60S WILL
LEAD TO MODERATE AFTERNOON INSTABILITY FROM SRN APPALACHIANS EWD
ACROSS THE CAROLINAS WITH MLCAPES AOA 1500 J/KG COMMON. WHILE LARGE
SCALE FORCING MECHANISMS ARE NOT EVIDENT....THE INSTABILITY LINE NOW
MOVING EWD ACROSS TN WILL ENCOUNTER A MDTLY UNSTABLE AND UNCAPPED
AIR MASS AS IT APPROACHES THE SRN APPALACHIANS EARLY THIS AFTERNOON.
THUS HAVE EXTENDED THE SLIGHT RISK WWD INTO ERN TN FOR THIS
SCENARIO. AS LOW CLOUDS DISSIPATE EARLY THIS AFTERNOON E OF
APPALACHIANS...CONDITIONS WILL SUPPORT SCATTERED THUNDERSTORMS IN A
RELATIVELY LOW SHEAR ENVIRONMENT. HOWEVER CONDITIONS WILL FAVOR
LARGE HAIL AND LOCAL DAMAGING WINDS GIVEN THE AMOUNT OF INSTABILITY
THAT WILL BE PRESENT. A MORE ORGANIZED LINE OF STORMS COULD MOVE
OFF THE SRN APPALACHIANS BY MID AFTERNOON WITH BOTH A WIND AND HAIL
THREAT.

..HALES/ROGERS.. 05/13/2011

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

No comments: