[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 121611
SWODY1
SPC AC 121609

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1109 AM CDT MON SEP 12 2005

VALID 121630Z - 131200Z

THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 S
ANW 30 NNE ANW 20 WNW MHE 35 W RWF 30 SSE FRM 35 N OMA 25 N GRI 40 S
ANW.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 85 WNW
ANJ 25 S LSE 40 SE OMA 15 SW HSI 15 NNE LBF 55 N CYS DGW 55 NNW DGW
15 N 81V 65 SSE Y22 55 NNE ATY 25 NNE ELO.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM APN 35 NW MKG 30 WNW
MLI 10 SSE IRK 35 SW SZL 10 SE BVO 45 NW MLC 35 E DAL 20 SSW BPT
...CONT... 40 SW DMN 15 S 4SL 40 NW CAO 45 SSW LAA 15 NW LAA 25 ESE
LIC 35 NW LIC 35 SSW 4FC 20 N GJT 10 SW PUC 30 E DPG 35 SSW PIH 20
NNE MQM 40 S BZN 20 W MLS 20 E P24 70 NE DVL.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 SSE SRQ 35 N GNV
15 WNW SAV 30 N CHS 15 NNE EWN HSE.

...THERE IS A MDT RISK OF SVR TSTMS OVER PORTIONS OF NERN NEB/SERN
SD/NWRN IA/SWRN MN...

...THERE IS A SLGT RISK OF SVR TSTMS FROM FAR ERN WY INTO THE NRN
GREAT LAKES...

...SYNOPSIS...
PATTERN WILL REMAIN DOMINATED TODAY BY STRONG UPPER TROUGH NOW
LIFTING NEWD TOWARD WY.  SYSTEM WILL REMAIN NEGATIVELY TILTED WITH
ASSOCIATED 45-55 KT MID LEVEL JET OVERSPREADING THE CENTRAL PLAINS
THROUGH THE PERIOD.  AHEAD OF THIS MAIN FEATURE...A WEAKER SHORTWAVE
TROUGH IS SUSTAINING AN AREA OF ELEVATED CONVECTION FROM ERN SD
ACROSS MUCH OF MN THIS MORNING.  THIS SYSTEM...WITH ACCOMPANYING
ASCENT AND CONVECTION...WILL SHIFT NNEWD THROUGH THE DAY.  AT THE
SURFACE A FRONT WILL REMAIN QUASI-STATIONARY FROM NRN MN INTO SERN
SD/N-CENTRAL NEB...WHILE STRONGER N-S ORIENTED COLD FRONT ASSOCIATED
WITH CENTRAL ROCKIES UPPER TROUGH BECOMES BETTER DEFINED AND SHIFTS
EWD ACROSS ERN WY THIS AFTERNOON.  A SURFACE LOW SHOULD FORM ALONG
TRIPLE POINT OVER FAR WRN NEB/ERN WY LATER TODAY AND DEEPEN AS IT
MOVES EWD ACROSS NRN NEB OVERNIGHT.  PRIMARY SEVERE THREAT SHOULD
EVOLVE LATER TODAY AND THIS EVENING BOTH NEAR THE SURFACE FRONT OVER
SERN SD/N-CENTRAL AND NERN NEB...AND INTO THE HIGH PLAINS OF FAR ERN
WY/SWRN SD/WRN NEB INVOF STRONGEST LARGE SCALE ASCENT. 

...NERN SD INTO THE NRN GREAT LAKES...
INITIAL CONVECTION ASSOCIATED WITH EJECTING SYSTEM OVER ERN SD/MN
SHOULD REMAIN ELEVATED ALONG AND NORTH OF QUASI-STATIONARY SURFACE
FRONT...EVEN WITH MODEST HEATING THIS AFTERNOON. GIVEN STEEP MID
LEVEL LAPSE RATES FEEDING THE STORMS FROM THE SW AND MODEST CLOUD
LAYER SHEAR IN PLACE...A FEW STRONGER CELLS MAY DEVELOP MID LEVEL
ROTATION AND PRODUCE LARGE HAIL.  EXCEPTION MAY BE OVER NRN WI/SERN
MN INTO THE WRN U.P. OF MI WHERE WARM SECTOR SHOULD BECOME
MODERATELY UNSTABLE THIS AFTERNOON.  LAPSE RATES AT GRB WERE QUITE
WEAK THIS MORNING AND MAY BE MAIN LIMITING FACTOR FOR SEVERE
THUNDERSTORM DEVELOPMENT EWD INTO THIS REGION.

...ERN SD/ERN NEB INTO SWRN MN/IA...
MORNING MODELS CONTINUE TO DEVELOP QPF NEAR THE FRONT OVER THE
CENTRAL PLAINS AFTER 21Z...DESPITE THE MORE LIMITED LARGE SCALE
ASCENT ACROSS THE REGION IN WAKE OF EJECTING SYSTEM THIS AFTERNOON. 
A MOIST AND STRONGLY UNSTABLE AIR MASS IS EXPECTED INTO MUCH OF
ERN/CENTRAL NEB AND WRN IA...WHERE AFTERNOON HEATING WILL SUPPORT
2000+ J/KG MLCAPE.  IN ADDITION...COMBINATION OF HEATING AND LARGE
SCALE ASCENT WITHIN COUPLED UPPER JET STRUCTURE MAY INDUCE WEAK
CYCLOGENESIS ALONG THE FRONT INTO N-CENTRAL NEB/FAR SERN SD LATER
TODAY...AS FORECAST BY THE RUC.  THIS WILL INCREASE BOTH CONVERGENCE
AND DEEP LAYER SHEAR BETWEEN 21-00Z...SUGGESTING ANY STORMS WHICH
CAN DEVELOP WILL QUICKLY BECOME SEVERE.  EFFECTIVE LAYER SHEAR IS
FORECAST TO BE MARGINAL...YET STILL SUFFICIENT...FOR SUPERCELLS
/I.E. BETWEEN 35-45 KT/ WITHIN DEEP SWLY FLOW IN WAKE OF SHORTWAVE
TROUGH THIS MORNING.  THEREFORE...OVERALL EVOLUTION INTO
LINES/CLUSTERS WILL LIKELY OCCUR AS ACTIVITY DEVELOPS ESEWD THROUGH
THE EVENING.  LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY SEVERE
THREATS WITH EXPECTED COVERAGE WARRANTING HIGHER PROBABILITIES/MDT
RISK...THOUGH ISOLATED TORNADOES ARE ALSO POSSIBLE.

...FAR ERN WY/WRN NEB INTO CENTRAL NEB/SRN SD...
AIR MASS REMAINS QUITE DRY IN WAKE OF PREVIOUS COLD FRONT ACROSS
THIS REGION ATTM.  HOWEVER...STRONG ASCENT AND INCREASING ESELY FLOW
SHOULD SUPPORT MID 40F SURFACE DEW POINTS AND MARGINAL INSTABILITY
INTO FAR ERN WY/NEB PANHANDLE LATE TODAY.  VERY STRONG SHEAR AND
ENHANCED/DEEP ASCENT SHOULD THEREFORE SUPPORT INCREASING
THUNDERSTORMS OVER THE HIGH PLAINS THROUGH THE EVENING...WHICH WILL
SPREAD EWD ACROSS NEB/SRN SD OVERNIGHT.  SHOULD THESE STORMS REMAIN
SURFACE-BASED...DAMAGING WINDS AND LARGE HAIL WILL LIKELY BE COMMON
WITH STRONGER CELLS.  LARGE HAIL SHOULD BECOME PRIMARY THREAT ONCE
STORMS BECOMING ELEVATED AFTER DARK.

...FAR ERN NC...
A LOW PROBABILITY FOR A TORNADO HAS BEEN ADDED OVER FAR ERN NC AS
RAINBANDS FROM T.S. OPHELIA APPROACH THE OUTER BANKS LATER TODAY AND
TONIGHT.

..EVANS/BANACOS.. 09/12/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
WILL PROVIDE DETAILS ON THE TRANSITION.