[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 091731
SWODY2
SPC AC 091729

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1229 PM CDT FRI JUN 09 2006

VALID 101200Z - 111200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN/CENTRAL ROCKIES
EWD ACROSS THE CENTRAL PLAINS INTO PORTIONS OF THE MID MS/TN/LOWER
OH VALLEYS...

...SYNOPSIS..
LARGE UPPER RIDGE...CURRENTLY LOCATED OVER THE CENTRAL PORTIONS OF
THE COUNTRY...WILL FLATTEN BY SATURDAY AS A SERIES OF SHORTWAVE
TROUGHS EJECT NEWD FROM THE SWRN U.S. INTO THE PLAINS STATES. THIS
WILL RESULT IN 30-50 KT WLY MID LEVEL FLOW TO EXTEND W TO E ACROSS
THE CENTRAL CONUS. UNDER THIS STRONGER MID LEVEL FLOW...A
QUASI-STATIONARY COLD FRONT IS FORECAST TO EXTEND FROM ERN WY/CO EWD
ACROSS KS/MID MS VALLEY/LOWER OH VALLEY INTO NC BY LATE IN THE DAY.
THIS PATTERN SHOULD SUPPORT SEVERAL MCS EPISODES TO SPREAD
EWD...MAINLY ALONG AND NORTH OF THE FRONT...FROM THE ROCKIES/CENTRAL
PLAINS ESEWD INTO THE LOWER OH VALLEY/TN VALLEY REGION.

...MID MS/LOWER OH/TN VALLEYS...
A WEAKENING MCS IS LIKELY BE ONGOING AT THE START OF THE PERIOD IN
IL. WEAK WARM ADVECTION IS EXPECTED TO MAINTAIN THIS CONVECTION AS
WNWLY FLOW ALOFT PUSHES THIS SYSTEM INTO THE LOWER OH VALLEY/ERN TN
VALLEY REGION DURING THE AFTERNOON. WITH HEATING...MLCAPES BETWEEN
1000-1500 J/KG AND 30-40 KT DEEP LAYER SHEAR MAY AID STORM
INTENSIFICATION. WIND DAMAGE IS EXPECTED TO THE MAIN THREAT GIVEN
THE 30-50 KT WNWLY WINDS THAT WILL BE LOCATED ABOVE THE BOUNDARY
LAYER. STORMS ARE EXPECTED TO WEAKEN AS THEY CROSS THE APPALACHIANS
AND ENCOUNTER A MORE STABLE ENVIRONMENT.

ETA/GFS ARE BOTH SUGGESTIVE OF SHORTWAVE TROUGH MOVING INTO KS/OK
LATE IN THE DAY. THIS WILL INCREASE THE LOW LEVEL JET/WARM ADVECTION
NORTH OF THE FRONT ACROSS PORTIONS OF ERN KS/WRN MO.
THE LIFT ASSOCIATED WITH THESE FEATURES SHOULD AID STORM INITIATION
ACROSS PORTIONS OF KS/MO LATE IN THE DAY. ALTHOUGH FORECAST OF MID
AND UPPER 60 DEWPOINTS WILL LIKELY BE CONFINED CLOSE TO THE
SURFACE...STEEP MID LEVEL LAPSE RATES WILL LIKELY RESULT IN AT LEAST
MODERATE INSTABILITY. STRENGTHENING...MOSTLY UNIDIRECTIONAL...WLY
WINDS ABOVE THE BOUNDARY LAYER SHOULD RESULT IN 30-40 KT OF DEEP
LAYER SHEAR. THE LARGE SCALE LIFTING COMBINED WITH THE SHEAR AND
DEGREE OF INSTABILITY SHOULD RESULT IN SEVERE STORMS DEVELOPING IN
ERN KS/WRN MO LATE IN THE DAY. THE UNIDIRECTIONAL FLOW ALOFT SHOULD
HELP TO CONSOLIDATE UPDRAFTS INTO AND MCS WITH THE SYSTEM MOVING
ESEWD OVERNIGHT INTO THE LOWER OH VALLEY.

...NRN ROCKIES/HIGH PLAINS...
MODELS SUGGEST SHORTWAVE TROUGH AND 50 KT JET MAX WILL MOVE EWD INTO
THE REGION...WHERE ELY UPSLOPE FLOW WILL BE MOISTENING BOUNDARY
LAYER. THE COMBINATION OF LARGE SCALE LIFTING AND UPSLOPE FLOW
SHOULD RESULT IN NUMEROUS THUNDERSTORMS TO DEVELOP DURING THE
AFTERNOON ACROSS THE HIGHER TERRAIN FROM MT SWD INTO NRN CO.
VERTICAL SHEAR PROFILES WILL SUPPORT SUPERCELLS DUE TO STRONG
VEERING WIND PROFILES AND 40-50 KT MID LEVEL WINDS. ALTHOUGH THE
SHEAR AND INSTABILITY MAY SUPPORT A COUPLE OF TORNADOES...THE
ACTIVITY IS EXPECTED TO MERGE INTO A FEW COMPLEXES AND THEN MOVE
SEWD INTO THE PLAINS WITH HAIL/WIND THE MAIN THREATS.

..SRN PLAINS....
MID/HIGH LEVEL TROPICAL MOISTURE FROM THE ITCZ IS EXPECTED TO STREAM
NEWD FROM MEXICO ACROSS TX INTO WRN OK/SRN KS. INTENSE HEATING
SHOULD HELP TO CREATE DRY ADIABATIC LAPSE RATES FROM THE SURFACE TO
THE LFC...AROUND 10 KFT...WHICH SHOULD AID IN HIGH BASE CONVECTIVE
DEVELOPMENT DURING THE AFTERNOON. THE DEEP WELL MIXED BOUNDARY LAYER
MAY BE SUFFICIENT IN GENERATING ISOLATED SEVERE WIND GUSTS BETWEEN
21-03Z.

..IMY.. 06/09/2006