SWOD48
SPC AC 080959
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0359 AM CST SUN FEB 08 2009
VALID 111200Z - 161200Z
...SEVERE STORMS POSSIBLE EAST OF THE MISSISSIPPI VALLEY INTO THE
APPALACHIANS THIS COMING WEDNESDAY...
MEDIUM RANGE FORECAST GUIDANCE CONTINUES TO INDICATE THAT A REGIONAL
SEVERE WEATHER THREAT DEVELOPING LATE TUESDAY/TUESDAY NIGHT WILL
CARRY OVER INTO AT LEAST EARLY WEDNESDAY. MREF MEMBERS SUGGEST A
HIGH LIKELIHOOD FOR A PRE-FRONTAL TONGUE OF LOW-LEVEL
MOISTURE...CHARACTERIZED BY MID 5OS SURFACE DEW POINTS...TO EXTEND
AS FAR NORTH AS THE MISSISSIPPI/OHIO RIVER CONFLUENCE AT 12Z
WEDNESDAY. AND...THIS MAY CONTRIBUTE TO ENOUGH INSTABILITY TO
MAINTAIN A SQUALL LINE EAST OF THE MISSISSIPPI RIVER...PERHAPS AS
FAR AS THE WESTERN SLOPES OF THE APPALACHIANS...AHEAD OF A VIGOROUS
SHORT WAVE TROUGH ACCELERATING THROUGH THE OHIO VALLEY DURING THE
DAY. STRONGLY FORCED CONVECTION WILL BE EMBEDDED WITHIN A VERY
STRONG MEAN ENVIRONMENTAL FLOW /GREATER THAN 50 KT/ CAPABLE OF
SUPPORTING CONSIDERABLE DAMAGING WIND GUSTS...EVEN IF THERMODYNAMIC
PROFILES BECOME DECREASINGLY FAVORABLE FOR LIGHTNING ACTIVITY WITH
EASTWARD PROGRESSION. SOUTH OF THE TENNESSEE VALLEY...STORM
DEVELOPMENT AHEAD OF THE FRONT MAY BECOME MORE DISCRETE IN THE
PRESENCE OF WEAKER MID-LEVEL FORCING/GREATER INHIBITION.
BUT...PRE-FRONTAL DEEP LAYER SHEAR IS EXPECTED TO REMAIN FAVORABLE
FOR SUPERCELLS AS FAR SOUTH AS THE CENTRAL/EASTERN GULF COAST.
THEREAFTER...UPSTREAM WAVES PROGRESSING THROUGH THE PROMINENT BELT
OF WESTERLIES ACROSS THE SOUTHERN TIER OF THE U.S. MAY SUPPORT
ADDITIONAL RISKS FOR SEVERE STORMS LATE THIS COMING WEEK INTO NEXT
WEEKEND. BUT...THE PREDICTABILITY OF THESE SYSTEMS IS TOO LOW TO
CONFIDENTLY DELINEATE ADDITIONAL AREAS...DUE TO THE INCREASINGLY
LARGE SPREAD AMONG MODEL DATA AT THIS EXTENDED RANGE.
..KERR.. 02/08/2009
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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