[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 041741
SWODY2
SPC AC 041740

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1240 PM CDT WED MAY 04 2005

VALID 051200Z - 061200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 ENE CTB HVR 80 WNW
MLS SHR RWL 45 SW LAR FCL AIA PIR INL ...CONT... 45 ESE ANJ PLN MTW
CID FNB MHK ICT END MWL SEP HDO COT 45 S LRD ...CONT... ELP TCS INW
FLG EED RAL 40 NE SBA 30 ENE SFO 40 WSW MHS EUG PDX 4OM 35 N 63S.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 S MOB TCL 35 NNW
BHM 25 NNE GAD RMG ATL MCN 45 S AGS FLO FAY RWI 35 E ORF.

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
PROGRESSIVE MID/UPPER LEVEL PATTERN FCST AS ERN CANADIAN VORTEX
WEAKENS.  SRN STREAM SHORTWAVE TROUGH PRESENTLY OVER SABINE RIVER
REGION IS FCST TO CONTINUE MOVING EWD ACROSS GULF COAST STATES. 
THIS FEATURE IS INDUCING WEAK SFC CYCLOGENESIS ATTM OVER E-CENTRAL
GULF -- ALONG QUASISTATIONARY SFC FRONT.  THIS FRONT WILL REMAIN
ACROSS CENTRAL FL AND DELINEATE NRN BOUND OF SEVERE PROBABILITIES
UNTIL PASSAGE OF DEEPENING FRONTAL-WAVE CYCLONE NEWD ACROSS
PENINSULA...LIKELY THROUGH FIRST 6 HOURS OF PERIOD.
NRN STREAM MID/UPPER LEVEL PERTURBATION -- NOW EVIDENT IN MOISTURE
CHANNEL IMAGERY OVER KANSAS CITY AREA -- WILL PIVOT EWD NEARLY IN
PHASE WITH AFOREMENTIONED SRN STREAM TROUGH...CONTRIBUTING
ADDITIONALLY TO LOW LEVEL CYCLOGENESIS OFFSHORE GA/SC/NERN FL. GEN
TSTMS MAY OCCUR IN ELEVATED WAA CONVEYOR BUT SFC-BASED INSTABILITY
AND SEVERE THREAT SHOULD REMAIN OFFSHORE GA/SC.

MEANWHILE...12Z RAOB DATA AND MOISTURE CHANNEL IMAGERY INDICATE TWO
SMALL NRN STREAM VORTICITY MAXIMA ALOFT OVER NRN AND SRN SASK. 
THESE FEATURES ARE PROGGED TO MOVE SEWD ACROSS SRN MANITOBA...NRN MN
AND ERN ND DURING DAY-2 PERIOD.  ASSOCIATED SFC COLD FRONT WILL MOVE
SEWD OVER UPPER MS VALLEY...ACCOMPANIED BY WEAK FRONTAL-WAVE
CYCLOGENESIS OVER MN BY AFTERNOON.  TRAILING PORTION OF SFC FRONT --
SWWD TOWARD BLACK HILLS AREA...SHOULD STALL BY 06/00Z THEN RETREAT
NWD AS WARM FRONT.

HIGH AMPLITUDE MIDLEVEL TROUGH WILL MOVE ONSHORE W COAST AND OVER
PORTIONS GREAT BASIN BY END OF PERIOD...CONTRIBUTING ENOUGH
DESTABILIZATION ALOFT TO SUPPORT GEN TSTM POTENTIAL OVER MUCH OF WRN
CONUS.

...CENTRAL/SRN FL PENINSULA...
SCATTERED-NUMEROUS TSTMS MAY BE ONGOING AT BEGINNING OF PERIOD OVER
REGION...WITH COVERAGE EXPECTED TO BE GREATEST OVER CENTRAL FL NEAR
FRONT. VERTICAL WIND PROFILES IN AREA OF BACKED BOUNDARY LAYER FLOW
- AHEAD OF SFC WAVE CYCLONE -- MAY SUPPORT SUPERCELLS AND SMALL BOW
ECHOES.  FCST HODOGRAPHS IN THAT REGIME SHOW LOOPINESS IN LOWEST 2-3
KM AGL WITH 0-1 KM SRH 100-200 J/KG AND EFFECTIVE DEEP-LAYER SHEARS
35-40 KT.  ALTHOUGH TORNADO OR DAMAGING GUSTS CANNOT BE RULED
OUT...LARGE COVERAGE OF PRECEDING CLOUD/PRECIP LIKELY...ACROSS AREA
OF GREATEST PROGGED SHEAR...MAKES THREAT TOO CONDITIONAL TO EXTEND
DAY-1 CATEGORICAL SGLT RISK INTO THIS PERIOD.  AFTER WAVE CYCLONE
MOVES OFFSHORE NERN FL COAST...SEVERE POTENTIAL WILL DIMINISH AS
ISALLOBARICALLY FORCED VEERING OF BOUNDARY LAYER FLOW WEAKENS
CONVERGENCE ASSOCIATED WITH COLD FRONT.

...UPPER MIDWEST...
WIDELY SCATTERED TSTMS MAY DEVELOP INVOF SFC LOW AND SWWD ALONG COLD
FRONT DURING MID/LATE AFTERNOON...WEAKENING AFTER DARK BECAUSE OF
LOSS OF SUPPORTING SFC HEATING.  SEPARATE AREA OF ELEVATED
CONVECTION MAY DEVELOP DURING AFTERNOON OR AFTER DARK -- E THROUGH
NE OF SFC WAVE.  LACK OF MORE SUBSTANTIAL MOISTURE PRECLUDES
ORGANIZED SEVERE POTENTIAL...HOWEVER COMBINATION OF COLD AIR ALOFT
AND WELL MIXED BOUNDARY LAYER MAY SUPPORT MARGINAL WIND/HAIL THREAT
WITH FRONTAL ACTIVITY. PRIND SFC MOISTURE RETURN FCST BY ETA IS TOO
AGGRESSIVE CONSIDERING TRAJECTORY ORIGINATION FROM GREAT LAKES/OH
VALLEY CONTINENTAL RIDGING AREA...AND 850 MB FLOW EMANATING FROM
RAIN-COOLED AND RELATIVELY LOW THETAE AIR MASS NOW OVER W TX. 
RELATIVELY DRY SFC DEW POINTS UPPER 30S/40S F...COMBINED WITH SFC
HEATING...LEAD TO MLCAPE 500-800 J/KG AND HIGH STORM BASES IN
MODIFIED MODEL SOUNDINGS OVER THIS REGION.  ELEVATED TSTMS MAY
PRODUCE HAIL NEAR SEVERE LEVELS AS WELL...WITH SIMILAR BUOYANCY
VALUES USING ELEVATED PARCELS.

...SRN PLAINS TO SRN ROCKIES...
WIDELY SCATTERED TO ISOLATED TSTMS POSSIBLE DURING AFTERNOON/
EVENING FROM ERN MOUNTAINS OF NM EWD TO LOW ROLLING PLAINS OF NW TX.
 VERTICAL SHEAR WILL INCREASE WITH EWD EXTENT AS FLOW ALOFT
VEERS...BECAUSE OF UPPER RIDGE POSITIONING OVER ERN NM.  STRONG
DEEP-LAYER DIRECTIONAL SHEAR AND ENLARGED 0-3 KM HODOGRAPHS LIKELY
OVER W-CENTRAL/NW TX...BUT IN ENVIRONMENT OF WEAK BOUNDARY LAYER
FORCING AND POSSIBLE RESTRICTIONS ON HEATING IMPOSED BY PRE-EXISTING
CLOUDS/PRECIP. MEANWHILE FARTHER W...STRONGER HEATING AND LOW LEVEL
LIFT...BUT WEAKER SHEAR...ARE EXPECTED ON HIGHER TERRAIN.  GIVEN
THESE OFFSETTING FACTORS...PRIND SEVERE WIND/HAIL MAY OCCUR IN A FEW
LOCALES BUT POTENTIAL IS TOO ISOLATED/CONDITIONAL FOR CATEGORICAL
OUTLOOK ATTM.

..EDWARDS.. 05/04/2005

...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.