[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 132000
SWODY1
SPC AC 131955

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0255 PM CDT MON SEP 13 2004

VALID 132000Z - 141200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 NW
ELO 15 SE MKT 40 WSW FOD 30 SSE HSI 20 SSE MCK 30 SSW IML 25 W IML
55 SW MHN 20 E ANW 20 W ATY 45 W RRT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 W MFE 60 SE LRD 45
WNW COT 30 NW SAT 15 W GGG HOT POF CMI 55 S CGX SBN FDY UNI PSK GSP
CAE HSE.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM MQT CWA OTM TOP RSL
GCK 35 WSW AMA 45 N HOB 55 SW INK 50 W MRF ...CONT... 50 SSW TUS SOW
CEZ U28 VEL 25 NE RWL CPR IDA 50 SSE BKE SLE 45 SSW AST.

...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MN SWWD TO CENTRAL/SWRN
NEB...

...SYNOPSIS...
BROADLY CYCLONIC MID/UPPER FLOW WILL CONTINUE AROUND WRN CONUS MEAN
TROUGH.  EMBEDDED SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE
CHANNEL IMAGERY OVER WRN DAKOTAS -- IS FCST TO EJECT NEWD ACROSS NRN
PLAINS THIS EVENING AND ACCELERATE TO NWRN ONT BY END OF
PERIOD...WHILE DEAMPLIFYING.  MEANWHILE ANOTHER MID/UPPER TROUGH
WILL DRIFT NEWD ACROSS TN VALLEY REGION.

AT SFC..COLD FRONT IS ANALYZED FROM FRONTAL WAVE LOW ALONG
ONT/MANITOBA BORDER...SWWD ACROSS NWRN MN AND SERN ND INTO ANOTHER
LOW BETWEEN JMS-ABR...THEN WSWWD ACROSS NWRN SD.  TWO SECONDARY
BOUNDARIES -- SFC TROUGHS WITH SOME BAROCLINIC CHARACTERISTICS --
EXTEND SWD TO SWWD FROM JMS/ABR LOW --
1. ACROSS NEB PANHANDLE TO EXTREME SERN WY AND
2. FROM NEAR HON-MHE-GLD-LIC.
EXPECT NRN TWO BOUNDARIES TO CONSOLIDATE/MERGE THROUGH REMAINDER
PERIOD ACROSS SD...WHILE SRN BOUNDARY REMAINS DISTINCT PREFRONTAL
TROUGH.

...UPPER MS VALLEY TO CENTRAL PLAINS...
STRONG CAPPING SHOULD BE MAINTAINED ACROSS MUCH OF THIS REGION BASED
ON MODIFIED 12Z RAOBS AND RUC FCST SOUNDINGS...AND POTENTIAL FOR
SFC-BASED CONVECTION GENERALLY BECOMES MORE CONDITIONAL WITH SWD
EXTENT FROM CENTRAL MN TO NERN NEB.  HOWEVER...EXPECT TSTMS TO
DEVELOP LATE THIS AFTERNOON INTO EARLY EVENING INVOF SFC COLD FRONT
WHERE BOUNDARY LAYER CONVERGENCE IS MAXIMIZED. 
ADDITIONALLY...ONGOING CONVECTION OVER CENTRAL/SWRN SD MAY BECOME
SFC BASED FARTHER E ACROSS ERN SD LATER THIS AFTERNOON.  INCREASING
LARGE SCALE ASCENT AHEAD OF NRN PLAINS TROUGH -- COMBINED WITH
CONTINUED INSOLATION AHEAD OF SFC FRONT AND 60S F SFC DEW POINTS --
WILL RESULT IN FAVORABLY BUOYANT AIR MASS WITH MLCAPES 1000-2000
J/KG RANGE BY 14/00Z.  STRONGEST VERTICAL SHEAR WILL BE OVER MN
WHERE 50 KT LLJ CONTRIBUTES TO 0-1 KM SRH IN 200-300 K/KG
RANGE...WITH 0-6 KM SHEARS GENERALLY 35-45 KT. THIS WILL SUPPORT
POTENTIAL FOR DISCRETE SUPERCELLS -- ESPECIALLY GIVEN CAP
STRENGTH...WITH ALL MODES OF SEVERE POSSIBLE.

ISOLATED TSTMS ALSO MAY DEVELOP IN INTENSELY HEATED/MIXED AIR MASS
ALONG/AHEAD OF SRN TROUGH...OVER SWRN NEB...WRN KS AND ERN CO. 
VERTICAL SHEAR SHOULD CONTINUE TO WEAKEN WITH SWD EXTENT ACROSS THIS
REGION...LIMITING ORGANIZATION AND LONGEVITY OF CONVECTION AS WELL
AS PROBABILITIES FOR ORGANIZED SEVERE. HOWEVER...A FEW CELLS MAY
BRIEFLY PRODUCE SEVERE HAIL/GUSTS BETWEEN 22Z-01Z.

...TN VALLEY REGION...
WIDELY SCATTERED TO SCATTERED MULTICELL TSTMS IN CLUSTERS ARE
EXPECTED THROUGH LATE EVENING IN THIS REGION.  LARGELY DIURNAL
POTENTIAL EXISTS FOR MARGINAL SEVERE HAIL AND ISOLATED DAMAGING WIND
INVOF MIDLEVEL TROUGH. WEAK LARGE SCALE ASCENT E OF TROUGH ALOFT --
COMBINED WITH CONTINUED DIABATIC HEATING AND FAVORABLE SFC MOISTURE
-- WILL CONTRIBUTE TO BUOYANCY IN ENVIRONMENT OF WEAKENING CINH. 
MLCAPES SHOULD REACH TO NEAR 1500 J/KG ACROSS MUCH OF THIS REGION
AWAY FROM CONVECTIVE OUTFLOW POOLS...BASED ON MODIFIED 18Z BMX/BNA
RAOBS. LOW-MIDLEVEL FLOW AND DEEP-LAYER SHEAR WEAKEN WITH NWD
EXTENT ACROSS CENTRAL AL INTO MID TN...PER LATEST VWP...18Z RAOBS
AND RUC FCST SOUNDINGS.  HOWEVER STRONG DIRECTIONAL SHEAR IS NOTED
PARTICULARLY OVER SRN MID TN AND AL...SUPPORTING ORGANIZED MULTICELL
POTENTIAL.  CONVECTION SHOULD WEAKEN AFTER APPROXIMATELY 3Z WITH
INTENSIFYING DIABATIC COOLING OF NEAR-SFC LAYER.

..EDWARDS.. 09/13/2004

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.