[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 300610
SWODY2
SPC AC 300608

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0108 AM CDT TUE MAY 30 2006

VALID 311200Z - 011200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN HIGH
PLAINS...

...SYNOPSIS...
MODELS ARE IN GENERAL AGREEMENT WITH THE TIMING OF THE CURRENT WRN
TROUGH WHICH SHOULD BE LOCATED OVER THE NRN HIGH PLAINS AT 12Z
WEDNESDAY.  THIS TROUGH SHOULD TRACK EWD TO THE UPPER MS VALLEY BY
WEDNESDAY EVENING...AND THEN AMPLIFY SEWD INTO THE WRN GREAT
LAKES/MID MS VALLEY IN RESPONSE TO HEIGHT RISES ACROSS MUCH OF WRN
NORTH AMERICA.

IN THE LOW LEVELS...A COLD FRONT EXTENDING FROM SRN ONTARIO AND SRN
GREAT LAKES REGION SWWD TO OK AND TX PANHANDLE SHOULD MOVE SLOWLY
SWD.  THIS BOUNDARY...THOUGH WEAK...IS EXPECTED TO REMAIN A FOCUS
FOR THUNDERSTORMS THROUGH THE DAY 2 FORECAST PERIOD.

...SRN HIGH PLAINS...
COLD FRONT INITIALLY EXTENDING ACROSS OK INTO THE TX PANHANDLE AT
12Z WEDNESDAY IS EXPECTED TO MOVE SWD AND SHOULD REACH CENTRAL AND
SW TX BY 12Z THURSDAY AS SURFACE HIGH PRESSURE BUILDS SWD ACROSS THE
PLAINS.  AT THE START OF DAY 2...ONE OR TWO MCS/S SHOULD BE ONGOING
ACROSS MAINLY KS AND OK IN RESPONSE TO WAA ALONG THE NOSE OF A
NOCTURNAL SLY LLJ EXTENDING FROM W TX INTO WRN KS.  THIS ACTIVITY IS
EXPECTED TO DIMINISH WEDNESDAY MORNING AS THE LLJ WEAKENS.

STEEP MID LEVEL LAPSE RATES ARE PROGGED TO BE CONFINED TO CO/NM INTO
W TX...WHERE COMBINED WITH SURFACE HEATING AND SURFACE DEWPOINTS IN
THE UPPER 50S WILL RESULT IN MODERATE INSTABILITY FROM W TX/ERN NM
INTO SERN CO.  MOIST UPSLOPE FLOW INTO NM/CO IS EXPECTED TO AID
THUNDERSTORM DEVELOPMENT WEDNESDAY AFTERNOON WITH ACTIVITY MOVING
SEWD WITHIN WNWLY MID LEVEL FLOW.  GIVEN THE WNWLY MID LEVEL FLOW
ATOP ESELY LOW LEVEL WINDS...DEEP LAYER SHEAR WILL BE SUFFICIENT
/30-40 KT/ FOR ORGANIZED STORMS.  ACTIVITY WILL LIKELY BECOME SEVERE
AS IT TRACKS SEWD INTO STRONGER INSTABILITY.  CONTINUATION OF
AFOREMENTIONED FLOW REGIME SHOULD SUPPORT THUNDERSTORMS...
POTENTIALLY IN THE FORM OF CLUSTERS...SPREADING SEWD ACROSS SWRN KS
AND INTO WRN OK/NW TX BY 12Z THURSDAY.

THUNDERSTORMS SHOULD ALSO DEVELOP ALONG THE SWD MOVING COLD FRONT
ACROSS OK AND PARTS OF NW TX...BUT THE COMBINATION OF WEAK MID LEVEL
LAPSE RATES...MARGINAL INSTABILITY AND WEAK DEEP LAYER SHEAR IS
EXPECTED TO LIMIT THE SEVERE POTENTIAL WEDNESDAY AFTERNOON/ EVENING.

...PARTS OF ERN DAKOTAS INTO WRN MN...
ONE OR TWO RESIDUAL SURFACE BOUNDARIES EXPECTED TO BE OVER THE
DAKOTAS INTO SW MN/NRN IA WILL PROVIDE THE FOCUS FOR THUNDERSTORMS
ON WEDNESDAY.  STEEP MID LEVEL LAPSE RATES AND ASCENT SPREADING EWD
ACROSS THIS REGION WITH THE UPPER TROUGH ARE EXPECTED TO AID IN
THUNDERSTORM DEVELOPMENT WEDNESDAY AFTERNOON/EVENING.  MODELS
SUGGEST SURFACE DEWPOINTS IN THE LOWER 50S MAY ADVECT NWD INTO THIS
AREA ON WEDNESDAY AIDING IN AT LEAST WEAK INSTABILITY FOR A FEW
SEVERE STORMS GIVEN STRONG DEEP LAYER SHEAR.

...SRN GREAT LAKES REGION/OH VALLEY TO MID MS/LOWER MO VALLEYS...
AIR MASS ALONG/S OF THE WEAK COLD FRONT IS EXPECTED TO REMAIN MOIST
WITH SURFACE DEWPOINTS IN THE 60S.  THIS COMBINED WITH SURFACE
HEATING SHOULD RESULT IN MODERATE INSTABILITY. THUNDERSTORMS WILL
LIKELY DEVELOP WITHIN THIS AIR MASS...BUT GENERALLY WEAK UPPER
FORCING COMBINED WITH WEAK MID LEVEL LAPSE RATES SHOULD LIMIT THE
NUMBER OF STORMS THAT CAN PRODUCE SUSTAINED UPDRAFTS.  IN
ADDITION...STRONGER MID LEVEL FLOW IS PROGGED TO REMAIN ON THE COLD
SIDE OF THE FRONT RESULTING IN WEAK DEEP LAYER SHEAR...FURTHER
INHIBITING THE POTENTIAL FOR STORM ORGANIZATION AND ATTENDANT SEVERE
THREAT.

..PETERS.. 05/30/2006