SWODY2
SPC AC 231715
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1215 PM CDT SAT MAY 23 2009
VALID 241200Z - 251200Z
...NO SVR TSTM AREAS FORECAST...
...MID-ATLANTIC/SRN NEW ENGLAND...
A BROAD LOW-AMPLITUDE UPPER-LEVEL TROUGH WILL MOVE EWD ACROSS THE
NERN STATES SUNDAY. AT THE SFC...A HIGH PRESSURE SYSTEM WILL SETTLE
INTO THE GREAT LAKES REGION AS A SLOW MOVING COLD FRONT MOVES SWD
ACROSS NEW ENGLAND AND THE MID-ATLANTIC COASTAL PLAINS. SCATTERED
THUNDERSTORMS SHOULD DEVELOP ALONG THE BOUNDARY AROUND MIDDAY AND
EXPAND IN COVERAGE SUNDAY AFTERNOON. FORECAST SOUNDINGS AT 21Z
SUNDAY ALONG THE BOUNDARY SHOW UPPER 60S F DEWPOINTS RESULTING IN
MODERATE INSTABILITY WITH MLCAPE VALUES OF 1500 TO 2000 J/KG. IN
ADDITION...20 TO 30 KT OF VERTICAL SHEAR WILL EXIST LARGELY DUE TO
STRONGER FLOW ON THE SRN EDGE OF MID-LEVEL JET OVER QUEBEC. THESE
FACTORS ALONG WITH ABOUT 20 KT OF FLOW ABOVE THE BOUNDARY LAYER AND
STEEP LOW-LEVEL LAPSE RATES SHOULD BE SUFFICIENT FOR A FEW
MARGINALLY SEVERE STORMS CAPABLE OF STRONG WIND GUSTS SUNDAY
AFTERNOON.
...CNTRL HIGH PLAINS...
A SUBTLE UPPER-LEVEL TROUGH IS FORECAST TO MOVE EWD ACROSS THE HIGH
PLAINS SUNDAY. BENEATH THE TROUGH...AN AXIS OF INSTABILITY SHOULD BE
IN PLACE FROM NERN CO NWD ACROSS WRN NEB...WRN SD AND ERN WY. AS SFC
TEMPS WARM SUNDAY...SCATTERED THUNDERSTORMS SHOULD DEVELOP IN THE
HIGHER TERRAIN AND IN THE PLAINS ALONG A LEE TROUGH. THE STRONGEST
THUNDERSTORMS SHOULD OCCUR IN THE LATE AFTERNOON NEAR THE
INSTABILITY AXIS WHERE FORECAST SOUNDINGS SHOW ABOUT 30 TO 35 KT OF
VERTICAL SHEAR. IN SPITE OF THE WARM MID-LEVEL TEMPS...FORECAST
SOUNDINGS SHOW STEEP ENOUGH LAPSE RATES FOR A MARGINAL HAIL THREAT.
IN ADDITION...30 KT OF FLOW AT 850 MB MAY SUPPORT A FEW STRONG WIND
GUSTS ESPECIALLY IF A LINE-SEGMENT CAN DEVELOP ACROSS THE REGION
LATE SUNDAY AFTERNOON.
..BROYLES.. 05/23/2009
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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