[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 291301
SWODY1
SPC AC 291259

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0759 AM CDT MON MAY 29 2006

VALID 291300Z - 301200Z

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY
TONIGHT FROM THE UPPER MS VALLEY INTO THE CENTRAL PLAINS...

...SYNOPSIS...
MAIN PATTERN IS MID/UPPER LEVEL TROUGH OVER THE WEST WITH RIDGING
OVER THE ERN THIRD OF THE U.S. SURFACE FRONTAL BOUNDARY EXTENDED
FROM NWRN MN SSWWD ACROSS SERN SD INTO SWRN KS AND THE OK PANHANDLE.


...CENTRAL MN INTO WRN WI..AND SWD INTO IA...

MODELS BRING SEVERAL SHORTWAVE TROUGHS AROUND BASE OF WRN U.S. FULL
LATITUDE TROUGH NNEWD INTO THE NRN PLAINS/NRN MN.  MUCH OF THE FLOW
IS UNIDIRECTIONAL...AND WOULD EXPECT LITTLE MOVEMENT EWD OF FRONTAL
BOUNDARY INTO EARLY THIS AFTERNOON.  NAM/GFS MOVE THE FRONT INTO ERN
MN SSWWD INTO EXTREME SERN NEB BY 2100Z.  ASSUME MUCH OF THIS WILL
BE DUE TO CONVECTION DEVELOPING ON/JUST BEHIND THE BOUNDARY WHERE
THERE WILL BE SOME SHEAR.  AHEAD OF THE FRONT...AIR MASS IS EXPECTED
TO BECOME VERY UNSTABLE DUE TO STRONG DAYTIME HEATING IN THE MIXED
LAYER. MLCAPE ARE PROJECTED TO BE 3000-4000 J/KG FROM CENTRAL MN
SSWWD INTO PARTS OF IA WITH SFC-3KM LAPSE RATES  AROUND 8.0-8.5C/KM
MOSTLY DUE TO HEATING. THIS AREA WILL ALSO BE IN FAVORABLE ENTRANCE
REGION OF MID/UPPER LEVEL JET STREAK EXTENDING FROM WRN NEB INTO
NERN ND BY TONIGHT ENHANCING UVVS ALONG THE BOUNDARY MOVING INTO
VERY UNSTABLE AIR MASS.  MAIN THREATS THIS AFTERNOON INTO EARLY
TONIGHT WILL BE LARGE HAIL AND DAMAGING WINDS SUPPORTED BY STEEP
LOW-MID LEVEL LAPSE RATES.

...AREA FROM IA SWWD THRU KS INTO WRN OK AND ERN TX PANHANDLE...

NAM MODEL DEVELOPS STRONG SLOW MOVING CONVECTION/MCS LATE THIS
AFTERNOON AND TONIGHT AS A WEAK SHORTWAVE TROUGH MOVES NEWD EMBEDDED
IN WEAKER MID LEVEL FLOW OVER SERN AZ INTO SERN CO.  DEVELOPMENT
WILL BE NEAR FRONTAL BOUNDARY/DRYLINE INTERSECTION.  SURFACE PROG
INDICATES SELY INTO ELY FLOW INTO AREA OF UPSLOPE FLOW AND DEW
POINTS POOLING IN THE MID/UPPER 60S WILL RESULT IN THUNDERSTORM/MCS
DEVELOPMENT IN VICINITY OF WEAK LOW OVER NWRN OK/TX PANHANDLE WHERE
STEEP LOW/MID LEVEL LAPSE RATES WILL BE AROUND 8C/KM AND MLCAPE WILL
BE AROUND 3000 J/KG.  POSSIBILITY EXISTS FOR LARGE HAIL AND
DOWNBURST WINDS THIS EVENING... DECREASING TONIGHT WITH LOSS OF
DAYTIME HEATING.

...PARTS NY INTO MA/CT/RI...

REMNANTS OF MCV MENTIONED IN MESOSCALE DISCUSSION 1019 ISSUED AT
1008Z CONTINUES TO MOVE SEWD ACROSS NERN NY STATE THIS MORNING. 
MORNING RAOB DATA FROM BUF SHOWS SOME MID LEVEL INSTABILITY
ASSOCIATED WITH MID LEVEL LAPSE RATES NEAR 7C/KM.  ACTIVITY WILL
MOVE SEWD THROUGH EARLY THIS AFTERNOON PRODUCING MOSTLY STRONG
STORMS WITH SOME SMALL HAIL.

..MCCARTHY/GUYER.. 05/29/2006