DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1240 PM CDT THU MAY 27 2010

VALID 281200Z - 291200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SOUTHEASTERN STATES...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NRN PLAINS...

...SYNOPSIS...
MODELS REMAIN CONSISTENT SHOWING BROAD UPPER TROUGH WILL PERSIST
FROM THE LOWER MS AND OH VALLEYS THROUGH AREAS SOUTH AND EAST OF THE
GULF AND SRN/MID ATLANTIC COASTS. WHILE A STRONGER DEEP CLOSED LOW
MOVES AWAY FROM THE NRN ATLANTIC COAST...A WEAK TROUGH SHOULD TRACK
SEWD FROM THE UPPER OH VALLEY TO THE MID ATLANTIC COAST ON DAY 2.
FARTHER W/SW...A SHORTWAVE TROUGH CURRENTLY LOCATED OVER WI/NRN
IL...WILL EVOLVE INTO A COMPACT CLOSED LOW AS IT MOVES SWD THROUGH
THE MID SOUTH TO THE LOWER MS VALLEY/CENTRAL GULF COAST STATES.

UPPER RIDGING WILL REMAIN STRONG THROUGH FRIDAY FROM THE SOUTHERN
PLAINS INTO THE UPPER MS VALLEY. SOME WEAKENING OF THIS RIDGE WILL
LIKELY COMMENCE FRIDAY NIGHT INTO EARLY SATURDAY ACROSS THE CENTRAL
AND NRN HIGH PLAINS AS THE LARGE-SCALE WESTERN U.S. UPPER TROUGH
MOVES SLOWLY EWD ACROSS THE INTERMOUNTAIN WEST AND ROCKIES. THE
MOST SIGNIFICANT EMBEDDED SHORT WAVE IMPULSE STILL APPEARS LIKELY TO
REMAIN W OF THE CENTRAL ROCKIES THROUGH 12Z SATURDAY. HOWEVER...A
LEAD IMPULSE/SPEED MAX WILL TRACK FROM THE BASE OF THE WRN TROUGH TO
THE NRN HIGH PLAINS BY LATE FRIDAY. THIS IMPULSE MAY PHASE WITH
SEVERAL WEAKER IMPULSES EMANATING FROM BAJA AND MEXICAN PLATEAU AND
MOVING NNEWD THROUGH THE CENTRAL HIGH PLAINS TO DAKOTAS.

...SERN STATES...
A MOIST AND MODERATELY UNSTABLE AIR MASS IS EXPECTED TO EXTEND FROM
THE OH VALLEY TO THE OZARKS/SRN PLAINS AND EWD TO THE GULF COAST AND
SRN/MID ATLANTIC STATES ON FRIDAY. TSTMS ARE EXPECTED TO DEVELOP
ACROSS MUCH OF THIS REGION...WITH ACTIVITY LIKELY ENHANCED IN THE
VICINITY OF A COUPLE WEAK SURFACE BOUNDARIES 1/ IN LEE OF THE SRN
APPALACHIANS...AND 2/FROM THE UPPER OH TO UPPER TN VALLEYS. FORCING
FOR ASCENT WITH THE UPPER OH VALLEY MID LEVEL TROUGH SHOULD SUPPORT
GREATER STORM COVERAGE ALONG THESE TWO BOUNDARIES. THE SRN EXTENT
OF SUFFICIENT EFFECTIVE BULK SHEAR /AROUND 30 KT/ FOR SOME STORM
ORGANIZATION WILL EXTEND SWD INTO VA/ERN NC. ALTHOUGH SHEAR WILL BE
WEAKER ELSEWHERE... DIVERGENT FLOW ALOFT IN LEE OF THE SRN
APPALACHIANS CONTINUES TO ALSO SUPPORT MORE TSTM DEVELOPMENT IN THIS
REGION. STRONG SURFACE HEATING/STEEPER LOW-LEVEL LAPSE RATES ACROSS
THE SLIGHT RISK WILL PROVE FAVORABLE FOR DOWNBURSTS AND EVOLVING
COLD POOLS ENHANCING THE THREAT FOR DAMAGING WIND GUSTS.