SWODY1
SPC AC 101930
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0130 PM CST THU MAR 10 2011
VALID 102000Z - 111200Z
...THERE IS A SLGT RISK OF SVR TSTMS CNTRL AND ERN NC AND VA INTO
THE DELMARVA...
...NC...VA...DELMARVA...
TRIMMED WRN EXTENT OF SEVERE PROBABILITIES TO REFLECT COLD FRONT
PASSAGE. THE REST OF THE AREA LOOKS TO BE ON TRACK.
SURFACE ANALYSIS SHOWS TEMPERATURES AND DEWPOINTS NEAR 60 F ACROSS S
CNTRL/SERN VA...WITH STRONG PRESSURE FALLS AS WELL. USING THESE
OBSERVATIONS IN CONJUNCTION WITH THE 18Z IAD SOUNDING SUGGESTS THAT
INSTABILITY AS DEPICTED BY CURRENT OA FIELDS MAY BE A BIT
UNDERDONE...ALTHOUGH STILL WEAK. WITH SUBSTANTIAL COOLING ALOFT AND
LIFT ALONG THE COLD FRONT...EXPECT LOW TOPPED CONVECTION TO INCREASE
OVER THE NEXT FEW HOURS. THE STRONGEST STORMS WILL BE CAPABLE OF
DAMAGING WIND GUSTS AND PERHAPS A BRIEF TORNADO GIVEN STRONG LOW
LEVEL SHEAR PROFILES.
...PACIFIC NW...
REMOVED LOW END WIND PROBABILITIES DUE TO LACK OF APPRECIABLE
INSTABILITY AND LACK OF LIGHTNING WITH CURRENT CONVECTION.
..JEWELL.. 03/10/2011
.PREV DISCUSSION... /ISSUED 1018 AM CST THU MAR 10 2011/
...NC/VA/SRN MD...
IMPRESSIVE DEEPENING OF SERN TROUGH OCCURRED OVERNIGHT WITH 5O0MB
12HR HEIGHT FALLS TO 180M NRN AL AT 12Z. TROUGH BECOMES NEGATIVELY
TILTED AND ROTATES NEWD ACROSS MID ATLANTIC STATES THIS
AFTERNOON/EVENING. STRONGLY FORCED LINE/S OF LOW TOPPED CONVECTION
WILL DEVELOP ALONG AND JUST E OF COLD FRONT WHICH EXTENDS SWD FROM
SURFACE LOW SWRN VA TO WRN SC/ERN GA AT 16Z.
WHILE LOW LEVEL MOISTURE IS SPREADING RAPIDLY NWD ON THE 40-50KT SLY
850MB JET THRU ERN NC INTO VA...THE LACK OF GOOD SFC HEATING AND
INITIALLY WEAK LAPSE RATES WILL GREATLY LIMIT INSTABILITY PRIOR TO
PASSAGE OF THE COLD FRONT LATER THIS AFTERNOON.
WITH DEWPOINTS RISING TO NEAR 60F AS FAR N AS CENTRAL VA BY MID
AFTERNOON...MLCAPES OF A COUPLE HUNDRED J/KG...WILL BE SUFFICIENT
GIVEN THE STRONG LARGE SCALE FORCING AND SHEAR ENVIRONMENT TO
CONTINUE A SEVERE THUNDERSTORM THREAT.
GIVEN THE IMPRESSIVE KINEMATICS OF THE TROUGH A RISK OF FAST MOVING
LOW TOPPED BOWING SEGMENTS EXPECTED TO DEVELOP BY EARLY AFTERNOON
FROM SRN VA SWD THRU CENTRAL NC. WITH BRN SHEAR TO 60KT...WIND
DAMAGE WILL BE PRIMARY CONCERN AS THE ACTIVITY MOVES RAPIDLY NEWD
ACROSS ERN VA/NC. THREAT COULD EXTEND AS FAR NE AS SRN MD PRIOR TO
WEAKENING IN A MORE STABLE AIR MASS ALONG THE COAST BY EVENING.
WITH EXPECTED STRONG LOW LEVEL SHEAR OF 30-40KT IN THE WARM SECTOR
OVER SERN VA/ERN NC...WILL MAINTAIN A LOW PROBABILITY OF EMBEDDED
SUPERCELLS AND BRIEF TORNADOES ASSOCIATED WITH THE LINEAR ACTIVITY.
...SRN FL...
THE STRONG LINE OF THUNDERSTORMS THAT MOVED ONSHORE CENTRAL FL THIS
MORNING IS NOW WEAKENING...HOWEVER GUSTY WINDS WILL CONTINUE TO
ACCOMPANY THE ORGANIZED COLD POOL. WILL CONTINUE TO MAINTAIN A LOW
PROB OF ISOLATED WIND DAMAGE UNTIL IT EXITS THE SERN COAST BY MID
AFTERNOON.
...WRN WA/NWRN OR...
STEEP LAPSE RATES AND STRONG SHEAR REMAIN W OF CASCADES IN THE
POST-FRONTAL AIR MASS IN ADVANCE OF THE COLD S/WV TROUGH. WILL
MAINTAIN A LOW PROBABILITY OF STRONG WINDS REACHING THE SURFACE WITH
ANY WEAK CONVECTION THAT MOVES ONSHORE THRU THIS AFTERNOON.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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:
Post a Comment