[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 100605
SWODY1
SPC AC 100603

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0103 AM CDT TUE MAY 10 2005

VALID 101200Z - 111200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 S
SNY 50 WNW BFF 35 WNW CDR 40 WNW VTN 15 SW OTG 40 WNW LNR 25 SSW MSN
20 N MMO 20 N SPI 25 S UIN 20 NW FNB 40 SSW IML 20 S SNY.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SE HUM 20 NW MEI
35 SW MKL 15 N ARG 35 NNE SGF 25 ESE CNU 25 ESE PNC 35 NNE FSI 30
SSW ABI 35 WSW JCT 70 W COT ...CONT... 95 SSE MRF 35 SE CNM 35 E TCC
45 N DDC 25 WNW HLC 25 NW GLD 20 SSW DEN 30 ENE GUC 20 ESE CEZ 60 SE
PGA 40 NNE IGM 15 NNW DRA 30 W BIH 25 SSE TVL 60 NW LOL 65 WNW OWY
20 E 27U 25 W MLS 25 NNE MBG 55 NNE MSP 10 SE GRR 30 W HTL 20 S ESC
20 SW MQT 40 NNE CMX ...CONT... 30 N PBG 10 SSE BGM 20 W NHK 25 SSE
OAJ ...CONT... 30 N DAB 20 SW CTY.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS NEB / IA AND VICINITY...

...SYNOPSIS...
MAIN MID-LEVEL FEATURE ACROSS THE CONUS THIS PERIOD WILL BE LARGE
UPPER LOW / TROUGH WHICH WILL CONTINUE SHIFTING EWD ACROSS THE GREAT
BASIN / ROCKIES.

IN RESPONSE TO THIS FEATURE...SURFACE CYCLOGENESIS IS FORECAST
ACROSS THE CENTRAL HIGH PLAINS.  WARM FRONT ASSOCIATED WITH THIS LOW
IS FORECAST TO SHARPEN WITH TIME...DIVIDING SLY LOW-LEVEL FLOW
ACROSS THE CENTRAL / SRN PLAINS AND NELY LOW-LEVEL WINDS ON SRN
PERIPHERY OF 1035 MB HIGH MOVING SWD ACROSS THE CANADIAN PRAIRIE. 
THIS STRENGTHENING / QUASISTATIONARY BAROCLINIC ZONE WILL ACT AS A
FOCUS FOR THUNDERSTORMS -- PARTICULARLY DURING THE LATTER HALF OF
THE PERIOD.

...NEB / IA AND VICINITY...
THUNDERSTORMS ARE FORECAST TO DEVELOP BY MID TO LATE AFTERNOON INVOF
SURFACE LOW / BAROCLINIC ZONE...AS MOIST / MODERATELY-UNSTABLE
AIRMASS IS ANTICIPATED ACROSS MUCH OF NEB AND IA NEAR AND S OF
FRONT. INITIAL DEVELOPMENT MAY OCCUR ACROSS ERN WY / WRN NEB JUST N
OF FRONT / LOW IN ELY UPSLOPE FLOW...BUT SHOULD OCCUR SHORTLY
THEREAFTER ACROSS PARTS OF NEB / IA IN LOW-LEVEL WARM ADVECTION /
ISENTROPIC LIFT JUST N OF FRONT.

STORMS SHOULD RAPIDLY BECOME SEVERE / SUPERCELLULAR...AS VEERING
LOW-LEVEL WINDS BENEATH 30 TO 40 KT WLY MID-LEVEL FLOW WILL FAVOR
UPDRAFT ROTATION.  THOUGH LARGE HAIL SHOULD BE THE MAIN SEVERE
THREAT...LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE...ALONG WITH
AN ISOLATED TORNADO OR TWO WITH ANY STORM NEAR / JUST N OF SURFACE
FRONT.

OVERNIGHT...STORMS SHOULD INCREASE IN COVERAGE ACROSS THIS REGION AS
LOW-LEVEL JET / WARM ADVECTION INCREASES INVOF SHARPENING FRONT. 
SEVERE THREAT SHOULD PERSIST / SHIFT EWD THROUGH MUCH OF THE NIGHT
AS LOW-LEVEL JET VEERS.

...FAR SERN NM / TRANSPECOS / SOUTH PLAINS OF TX...
THOUGH INITIATION REMAINS UNCERTAIN...SREF GUIDANCE HINTS THAT
ISOLATED CONVECTIVE DEVELOPMENT MAY OCCUR ALONG DRYLINE...FORECAST
TO MIX EWD TO A POSITION FROM JUST W OF CDS TO JUST E OF BGS DURING
THE AFTERNOON. THREAT FOR INITIATION MAY CONTINUE INTO THE EVENING
/ OVERNIGHT AS SELY LOW-LEVEL JET AND ASSOCIATED THETA-E ADVECTION
INCREASES ACROSS THIS REGION.  ASSUMING INITIATION OCCURS...MARGINAL
DEEP-LAYER SHEAR BUT MODERATE INSTABILITY SUGGESTS SUPERCELLS...WITH
LARGE HAIL THE MAIN SEVERE THREAT.  WILL INTRODUCE ONLY 5% SEVERE
PROBABILITY ATTM DUE TO UNCERTAINTIES REGARDING INITIATION.

...ERN UT / WY / WRN CO...
MARGINAL INSTABILITY IS EXPECTED ACROSS THIS REGION AS MID-LEVELS
COOL / UPPER TROUGH APPROACHES.  WITH MID-LEVEL JET STREAK SHIFTING
EWD ACROSS THIS REGION...SHEAR WILL BE SUFFICIENT FOR ORGANIZED /
SUPERCELL STORMS ASSUMING SUFFICIENT INSTABILITY FOR SUSTAINED
UPDRAFTS.

GIVEN LIMITED LOW-LEVEL MOISTURE / INSTABILITY EXPECTED ATTM...WILL
MAINTAIN ONLY 5% SEVERE HAIL / WIND PROBABILITIES.

..GOSS.. 05/10/2005

...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.