SWODY1
SPC AC 100548
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1148 PM CST SAT FEB 09 2008
VALID 101200Z - 111200Z
..NO SVR TSTM AREAS FORECAST...
..SYNOPSIS...
A GENERAL WNW FLOW REGIME IS EXPECTED TO PREVAIL ACROSS THE LOWER 48
STATES THIS FORECAST PERIOD. A CLOSED MID LEVEL LOW...INITIALLY
CENTERED OVER THE GREAT LAKES WILL PROGRESS EWD AND SHOULD REACH ERN
MAINE AND THE NOVA SCOTIA REGION BY 12Z MONDAY. MEANWHILE...A
PACIFIC TROUGH...CURRENTLY APPROACHING THE BC/WA COAST PER WATER
VAPOR IMAGERY...IS EXPECTED TO AMPLIFY SEWD TOWARD THE NRN/CENTRAL
ROCKIES BY LATE IN THE FORECAST PERIOD.
..PART OF NJ/SERN NY TO SRN NEW ENGLAND EARLY TODAY...
FAST MOVING ARCTIC COLD FRONT...ACCOMPANYING A NEGATIVELY-TILTED
LEAD SHORT WAVE TROUGH AHEAD OF GREAT LAKES CLOSED LOW...IS FORECAST
TO EXTEND FROM CENTRAL NY SWD THROUGH CENTRAL PA TO WRN VA/NC AT 12Z
TODAY. THIS FRONT WILL MOVE QUICKLY EWD AND SHOULD BE EAST OF MUCH
OF NEW ENGLAND...EXCEPT MAINE...BY LATE THIS AFTERNOON. STRONG
ASCENT WITHIN EXIT REGION OF 140+ KT MID LEVEL JET AND STEEPENING
LAPSE RATES SHOULD PROVE FAVORABLE FOR CONVECTIVE SHOWERS
ACCOMPANYING THE FRONTAL PASSAGE. GIVEN VERY COLD MID LEVEL
TEMPERATURES WITH THIS SYSTEM...SOME OF THE SHOWERS MAY BECOME DEEP
ENOUGH TO SUPPORT LIGHTNING PRODUCTION. FAST MOVEMENT OF SYSTEM/
FRONT SUGGESTS THAT OVERALL TSTM POTENTIAL SHOULD REMAIN LESS THAN
10 PERCENT...AND PRECLUDES INTRODUCTION OF A GENERAL TSTM AREA FOR
THIS REGION.
..PART OF CENTRAL AND NRN OK/SERN KS/FAR SWRN MO LATE TONIGHT...
ARCTIC COLD FRONT FORECAST TO EXTEND FROM CENTRAL AR/OK WNWWD INTO
THE CENTRAL HIGH PLAINS AT 12Z WILL CONTINUE TO SETTLE SWD INTO NRN
TX TODAY. A PORTION OF THIS BOUNDARY SHOULD RETREAT NWD TONIGHT
ACROSS OK AS A SWLY LLJ STRENGTHENS FROM NW TX INTO SERN KS IN
RESPONSE TO HEIGHT FALLS ACCOMPANYING A WEAK LEAD IMPULSE AHEAD OF
AMPLIFYING NRN/CENTRAL ROCKIES TROUGH. LOW LEVEL MOISTURE/WARM AIR
ADVECTION ATOP COLD STABLE BOUNDARY LAYER WILL BE GREATEST ALONG
AXIS OF LLJ INTO SERN KS LATE TONIGHT AIDING IN ELEVATED
DESTABILIZATION. MUCAPE AROUND 200 J/KG SHOULD BE SUFFICIENT FOR
TSTMS...MAINLY AFTER 11/09Z...FROM PARTS OF CENTRAL/NRN OK INTO SERN
KS/FAR SWRN MO. MOST OF THIS ACTIVITY IS EXPECTED TO DEVELOP ACROSS
A REGION WITH SUB-FREEZING SURFACE TEMPERATURES...SO THUNDER SLEET
AND FREEZING RAIN SHOULD BE COMMON WITH THESE STORMS.
..LEE OF LAKE ONTARIO THIS AFTERNOON/EVENING...
VERY COLD AIR MASS /AOB -20 C AT 850 MB/ EXPECTED TO SPREAD ACROSS
THE LOWER GREAT LAKES REGION THIS MORNING INTO THE AFTERNOON WILL
STEEPEN SFC-3 KM LAPSE RATES TO AT LEAST 8 C/KM. THIS MAY SUPPORT
DEEP ENOUGH CONVECTION FOR LIGHTNING PRODUCTION ALONG AND IN LEE OF
LAKE ONTARIO THROUGH THE AFTERNOON INTO THE EVENING PRIOR TO
LOWERING INVERSION HEIGHTS AS CLOSED LOW MOVES EAST OF REGION.
HOWEVER...OVERALL LIGHTNING POTENTIAL SHOULD REMAIN LESS THAN 10
PERCENT PRECLUDING INCLUSION OF GENERAL TSTM AREA.
.PETERS.. 02/10/2008
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@PO.UIUC.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.
No comments:
Post a Comment