[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 211738
SWODY2
SPC AC 211736

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1236 PM CDT MON JUN 21 2004

VALID 221200Z - 231200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 10 NE
HSE 25 WSW RDU 55 NNW AHN 15 WSW GWO 40 SE PGO 10 ENE HRO 30 SSW SDF
10 ENE HLG SYR SLK MPV CON 15 E ISP.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 NNW ANJ OSH ALO
SUX ANW AIA SNY 50 E LAA BVO UMN CGI LUK CMH ERI ...CONT... 40 ENE
CRP 10 SSW LRD ...CONT... 35 WSW FHU TUS 40 NE TUS SOW INW 60 NE INW
DRO 10 SE GUC 10 ESE CAG LND DLN S80 PDT RDM 60 NNE LMT MFR EUG PDX
25 ESE OLM 20 ENE BLI.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER MS/TN VALLEYS
INTO THE NORTHEAST STATES....

MODELS INDICATE BLOCKED UPPER FLOW PATTERN WILL PERSIST THROUGH THIS
FORECAST PERIOD AND BEYOND.  EMBEDDED WITHIN THIS REGIME...MOST
SIGNIFICANT FEATURE TO INFLUENCE THE U.S. APPEARS LIKELY TO BE DEEP
CLOSED LOW NOW EVOLVING OVER THE CENTRAL CANADIAN PROVINCES.  COLD
MID-LEVEL CIRCULATION CENTER IS PROGGED TO SLOWLY DEVELOP SOUTHWARD
ACROSS MANITOBA TUESDAY...WITH SERIES OF SHORT WAVE TROUGHS/JET
STREAKS ROTATING AROUND ITS WESTERN/SOUTHERN PERIPHERY.  IN BROADER
CYCLONIC UPPER FLOW REGIME TO THE SOUTH/EAST OF THIS FEATURE...
ANOTHER SHORT WAVE TROUGH IS PROGGED TO ACCELERATE EASTWARD ACROSS
THE LOWER GREAT LAKES/ST. LAWRENCE VALLEY REGION.

A COUPLE OF WEAKER BELTS OF WESTERLIES WILL PREVAIL OVER THE
SOUTHERN TIER STATES...ONE CURVING OUT OF THE SOUTH CENTRAL ROCKIES
INTO THE TENNESSEE VALLEY...THE OTHER CURVING AROUND NORTHERN
PERIPHERY OF SUBTROPICAL RIDGE OVER THE GULF/SOUTH ATLANTIC COAST
STATES.

...LOWER GREAT LAKES/UPPER OHIO VALLEY INTO NEW ENGLAND...
IN ASSOCIATION WITH SHORT WAVE TROUGH...MODELS INDICATE 50 TO 70 KT
JET STREAK SPREADING ACROSS WARM SECTOR AIR MASS OVER THE UPPER
OHIO/HUDSON VALLEY REGION DURING THE DAYTIME HOURS TUESDAY. 
STRONGER LOW-LEVEL WARM ADVECTION PRECIPITATION WILL DEVELOP
EASTWARD AHEAD OF THIS FEATURE...AND LINGERING CLOUD COVER IN ITS
WAKE PROVIDES SOME UNCERTAINTY WITH REGARD TO SURFACE HEATING AND
MAGNITUDE OF DESTABILIZATION ACROSS NEW YORK/PENNSYLVANIA. 
HOWEVER...WITH SURFACE DEW POINTS INCREASING THROUGH THE LOWER/MID
60S...ENOUGH INSOLATION APPEARS POSSIBLE TO CONTRIBUTE TO MEAN MIXED
LAYER CAPE IN EXCESS OF 1000 J/KG.  

THIS DESTABILIZATION WILL BE MORE THAN SUFFICIENT FOR SCATTERED
VIGOROUS CONVECTIVE DEVELOPMENT IN MODERATE TO STRONGLY SHEARED
ENVIRONMENT.  STRONG DAMAGING WIND GUSTS APPEAR LIKELY IN FAST
MOVING STORMS...WHICH SHOULD ORGANIZE IN SEVERAL SMALL LINES OR
CLUSTERS...WITH LARGE HAIL ALSO POSSIBLE IN STRONGEST CELLS. 
ACTIVITY IS EXPECTED TO SPREAD FROM THE LEE OF THE NORTHERN/CENTRAL
APPALACHIANS MID TUESDAY AFTERNOON...INTO PARTS OF SOUTHERN NEW
ENGLAND AND THE NORTHERN/MID ATLANTIC COASTAL AREAS BEFORE
DIMINISHING TUESDAY EVENING.

...GULF COAST STATES/LWR MS VLY/TENNESSEE VALLEYS...
MODELS CONTINUE TO INDICATE LARGE CONVECTIVE CLUSTER MAY BE ONGOING
ACROSS THE SOUTH CENTRAL PLAINS/RED RIVER VALLEY EARLY IN THE
PERIOD.  ACTIVITY LIKELY WILL WEAKEN DURING THE MORNING HOURS. 
HOWEVER...WITH SURFACE DEW POINTS IN THE LOWER/MID 70S ACROSS MUCH
OF THE SOUTHERN TIER STATES...MOIST/POTENTIALLY VERY BUOYANT AIR
MASS WILL SUPPORT RISK FOR RE-GENERATION OF ONE OR MORE CONVECTIVE
CLUSTERS.

BEST CHANCE APPEARS TO BE WITH REMNANT JET STREAK/CYCLONIC VORTICITY
CENTER WHICH WILL SHIFT EASTWARD OUT OF THE SOUTH CENTRAL PLAINS
TUESDAY MORNING...INTO THE TENNESSEE VALLEY BY LATE TUESDAY
AFTERNOON.  THOUGH HAIL THREAT APPEARS MINIMAL...ENHANCED
LOW/MID-LEVEL FLOW MAY CONTRIBUTE TO POTENTIAL FOR STRONG GUST FRONT
FROM THE PEAK HEATING HOURS INTO MID EVENING.

OLD OUTFLOW BOUNDARY ADVANCING SOUTH OF THE RED RIVER INTO EAST
TEXAS COULD BECOME FOCUS FOR ANOTHER CLUSTER OF STORMS.  FLOW FIELDS
WILL BE MUCH WEAKER ACROSS THIS AREA...BUT RELATIVELY DRY MID-LEVEL
ENVIRONMENT MAY CONTRIBUTE TO POTENTIAL FOR ISOLATED DOWNBURSTS.

...UPPER MISSISSIPPI VALLEY...
AREA OF STRONGER FORCING ASSOCIATED WITH LOW-LEVEL WARM ADVECTION
AHEAD OF DIGGING JET STREAK WILL CONTRIBUTE TO CONVECTIVE
DEVELOPMENT TUESDAY AFTERNOON FROM PARTS OF THE EASTERN DAKOTAS INTO
SOUTHERN MINNESOTA.  ALTHOUGH SURFACE DEW POINTS MAY ONLY RANGE FROM
THE UPPER 40S INTO LOWER  50S...COLD THERMODYNAMIC PROFILES AND
FAVORABLY SHEARED FLOW REGIME MAY BE SUPPORTIVE OF HAIL/GUSTY WINDS
IN STRONGER STORMS.  ACTIVITY MAY DEVELOP EASTWARD INTO PARTS OF
WISCONSIN BEFORE WEAKENING WITH LOSS OF HEATING DURING THE EVENING
HOURS.

..KERR.. 06/21/2004

...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.