[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 020601
SWODY1
SPC AC 020559

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1159 PM CST SAT APR 01 2006

VALID 021200Z - 031200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS EASTERN
MISSOURI...SOUTHEAST IOWA...MUCH OF ILLINOIS...SOUTHWEST
INDIANA...AND WESTERN KENTUCKY....

...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN FRINGES OF THE PLAINS
TO THE APPALACHIANS...

...SYNOPSIS...
MID-LEVEL SHORT-WAVE TROUGH IS FORECAST TO DEEPEN WHILE SHIFTING EWD
FROM THE PLAINS ACROSS THE MS VALLEY AND INTO THE UPPER GREAT
LAKES/OH AND TN VALLEYS THROUGH THE END OF THE PERIOD. A 70-PLUS KT
H5 JET STREAK IS FORECAST TO ACCOMPANY THIS TROUGH...WITH THE CORE
OF THIS JET EXPECTED FROM THE CENTRAL PLAINS EWD ACROSS THE
OZARKS/MID MS VALLEY REGION AND INTO THE TN AND OH VALLEYS.

AT THE SURFACE...LOW INITIALLY FORECAST OVER ERN NEB SHOULD DEEPEN
AND MOVE ENEWD WITH TIME...EVENTUALLY REACHING LOWER MI AS A 990 MB
CYCLONE.  WARM FRONT INITIALLY FORECAST TO EXTEND SEWD ACROSS MO
INTO THE SERN U.S. SHOULD LIFT NEWD ACROSS THE TN AND OH VALLEYS
WITH TIME...ALLOWING MOIST/UNSTABLE WARM SECTOR TO SPREAD ACROSS THE
MID MS VALLEY REGION AHEAD OF COLD FRONT.  THIS COLD FRONT SHOULD
CROSS MO DURING THROUGH THE AFTERNOON...AND THEN CONTINUE EWD ACROSS
THE OH VALLEY REGION THROUGH THE OVERNIGHT HOURS.  TRAILING PORTION
OF THE FRONT SHOULD SAG MORE SLOWLY SWD...LINGERING ACROSS AR AND TX
THROUGH THE END OF THE PERIOD.

...MID MS/OH/TN VALLEYS...
POTENTIALLY SIGNIFICANT SEVERE WEATHER EPISODE APPEARS TO BE SETTING
UP THIS PERIOD...CENTERED ON THE MID MS AND LOWER OH VALLEY REGION. 
THUNDERSTORMS SHOULD BE ONGOING AT THE START OF THE PERIOD ACROSS
THE MIDDLE AND LOWER MO VALLEY AHEAD OF APPROACHING UPPER TROUGH. 
THIS CONVECTION SHOULD SHIFT EWD/NEWD INTO THE UPPER GREAT LAKES
REGION THROUGH THE DAY.  THOUGH THIS INITIAL CONVECTION COMPLICATES
THE FORECAST DUE TO ITS POTENTIAL EFFECTS ON AFTERNOON
DESTABILIZATION...IT APPEARS ATTM THAT MOST OF THE CONVECTION SHOULD
VACATE THE MID MS VALLEY REGION BY AFTERNOON...ALLOWING DAYTIME
HEATING TO COMMENCE.  PRESUMING THIS OCCURS...1500 TO 2500 J/KG
MEAN-LAYER CAPE SHOULD DEVELOP ACROSS THE WARM SECTOR...AIDED BY NWD
ADVECTION OF LOW TO MID 60S DEWPOINTS BENEATH STEEPENING MID-LEVEL 
LAPSE RATES.

STORMS SHOULD REDEVELOP BY MID AFTERNOON -- LIKELY FROM SERN IA SWD
ACROSS THE ERN HALF OF MO AHEAD OF ADVANCING COLD FRONT.  DEEP-LAYER
WIND FIELD SHOULD BE QUITE STRONG ACROSS THIS REGION...AS POTENT
MID-LEVEL JET SHIFTS EWD INTO THE REGION.  ALONG WITH FAVORABLE
DEEP-LAYER SHEAR FOR SUPERCELLS...LOW-LEVEL SHEAR WILL ALSO BE
STRONG -- PARTICULARLY FROM ERN IA SWD ACROSS ERN MO AND IL NEAR AND
SE OF SURFACE LOW.  DEGREE OF LOW-LEVEL SHEAR ALONG WITH
MOIST/MODERATELY-UNSTABLE AIRMASS SUGGESTS THAT SEVERAL TORNADOES
WILL LIKELY OCCUR...A FEW OF WHICH COULD BE STRONG AND LONG-LIVED. 
ADDITIONALLY...LARGE HAIL AND LOCALLY DAMAGING WINDS ARE ALSO
EXPECTED.

WITH TIME...STORMS SHOULD BECOME MORE LINEAR -- PARTICULARLY ACROSS
THE OH VALLEY WHERE FLOW WILL BECOME MORE VEERED/UNIDIRECTIONAL WITH
HEIGHT THROUGH THE EVENING.  GIVEN STRENGTH OF THE WIND FIELD...MORE
ORGANIZED/WIDESPREAD DAMAGING WIND EVENT MAY EVOLVE/MOVE EWD ACROSS
THIS REGION.  STORMS SHOULD CONTINUE THROUGH THE END OF THE
PERIOD...WITH SEVERE THREAT EXTENDING AS FAR E AS THE CENTRAL
APPALACHIANS BY 03/12Z.

..GOSS.. 04/02/2006