[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 180049
SWODY1
SPC AC 180047

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0747 PM CDT MON APR 17 2006

VALID 180100Z - 181200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE NRN HIGH
PLAINS...

...WRN DAKOTAS/NWRN-NRN NEB...
VIGOROUS SHORT WAVE TROUGH MOVING INTO SWRN WY...AND LOCATED WITHIN
BASE OF COLD UPPER TROUGH OVER THE NRN INTERMOUNTAIN WEST/NRN
ROCKIES...WILL BECOME MORE NEGATIVELY TILTED OVERNIGHT AS IT
APPROACHES THE NRN HIGH PLAINS.  SSELY LLJ IS PROGGED TO STRENGTHEN
TO 60 KT ACROSS THE CENTRAL/NRN PLAINS IN RESPONSE TO HEIGHT FALLS
AHEAD OF THE UPPER TROUGH.  

EARLY EVENING SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING FROM
WRN ND SWWD THROUGH ERN WY TO WRN CO/SERN UT...WITH THIS BOUNDARY
MOVING EWD INTO THE PLAINS TONIGHT.  SURFACE LOW...NOW LOCATED OVER
FAR SERN WY EXPECTED TO DEVELOP SEWD ALONG WARM FRONT INTO CENTRAL
KS BY 12Z TUESDAY. 

INCREASINGLY DIFFLUENT FLOW AHEAD OF NEGATIVELY TILTED TROUGH AND
STRENGTHENING WAA REGIME WITH STRONG LLJ WILL SUPPORT CONTINUED
THUNDERSTORM DEVELOPMENT OVERNIGHT AS THE COLD FRONT MOVES EWD. 
SURFACE-BASED STORMS WILL REMAIN POSSIBLE ALONG THE COLD FRONT THIS
EVENING...WITH STORMS BECOMING MORE ELEVATED LATER THIS EVENING/
TONIGHT AS THE BOUNDARY LAYER COOLS.  STRONG DEEP LAYER SHEAR
VECTORS INITIALLY ORIENTED MORE NORMAL TO COLD FRONT WILL SUPPORT
DISCRETE STORMS FOR A FEW MORE HOURS...WITH EVENTUAL EVOLUTION INTO
A LINEAR MODE AS VECTORS BECOME ORIENTED PARALLEL TO FRONT.  LARGE
HAIL AND STRONG WIND GUSTS EXPECTED TO REMAIN PRIMARY THREATS GIVEN
STEEP LAPSE RATES...WITH HAIL BECOMING MAIN THREAT OVERNIGHT AS
ELEVATED ACTIVITY POTENTIALLY REACHES CENTRAL PARTS OF ND/SD/NRN
NEB. 

...SC...
SEVERE THREAT HAS ENDED ACROSS THE CAROLINAS AS STRONGEST FORCING
HAS SHIFTED OFFSHORE.  A FEW THUNDERSTORMS WILL REMAIN POSSIBLE
ACROSS MAINLY SRN SC FOR THE NEXT COUPLE OF HOURS AS WEAK WAA
PERSISTS ALONG TRAILING PORTION OF COLD FRONT /ANALYZED FROM NEAR
CHS-GSP AT 00Z/ MOVING SWD THROUGH THIS REGION.  CONTINUED AIR MASS
STABILIZATION SHOULD PRECLUDE ADDITIONAL SEVERE THREAT.

..PETERS.. 04/18/2006