[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 160548
SWODY1
SPC AC 160543

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1243 AM CDT THU SEP 16 2004

VALID 161200Z - 171200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 S
MOB MOB TCL HSV CHA AHN 65 ESE MCN VLD 35 ESE TLH.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 15 SE GPT 35 NW LUL
20 S GWO 30 N GLH 25 NE TXK 20 WSW TYR 20 ENE AUS 40 NE CRP
...CONT... 25 SSW P07 25 ENE HOB 40 WSW DHT 15 ENE AKO 25 SW MHN 30
ESE ANW 30 N GRI 25 SSE HSI 20 NE ICT 30 NNW BVO 20 WSW UMN 25 SE
TBN BLV 40 NE LAF 55 SE OSC ...CONT... 20 WNW EFK 25 SE GFL 30 NE
MSV 35 SW ABE 15 NW DCA SHD ROA 35 SE PSK 15 E RDU 35 ESE RWI 10 N
HSE.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 NW CMX 10 N IWD 40
N EAU MSP 50 SSW AXN 30 N ABR 45 E BIS 75 NW MOT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 E ISP ORH 20 S
PWM.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE EASTERN
GULF STATES....

BELT OF STRONGER SUBTROPICAL WESTERLIES WAS EVIDENT IN 16/00Z
SOUNDING DATA...CURVING ACROSS THE TEXAS BIG BEND THROUGH THE LOWER
MISSISSIPPI/TENNESSEE VALLEYS INTO THE MID ATLANTIC COAST STATES. 
AS HURRICANE IVAN GRADUALLY MAKES LANDFALL AND MERGES INTO THIS MORE
STRONGLY SHEARED ENVIRONMENT...A STEADY WEAKENING WILL ENSUE AS
SYSTEM SLOWLY MIGRATES NORTHEASTWARD ACROSS ALABAMA DURING THIS
FORECAST PERIOD.

MEANWHILE...POLAR WESTERLIES WILL REMAIN CONFINED TO THE VICINITY OF
THE CANADIAN/U.S. BORDER.  HOWEVER...SIGNIFICANT AMPLIFICATION OF
EMBEDDED SHORT WAVE IS PROGGED OFF THE PACIFIC NORTHWEST COAST LATE
THIS AFTERNOON INTO TONIGHT.  AS THIS OCCURS...DOWNSTREAM RIDGE WILL
BEGIN TO BUILD FROM THE NORTHERN INTERMOUNTAIN REGION INTO THE UPPER
MISSISSIPPI VALLEY...WHILE ANOTHER SIGNIFICANT SHORT WAVE TROUGH
LIFTS OUT OF THE UPPER GREAT LAKES INTO THE EASTERN CANADIAN
PROVINCES.

...EASTERN GULF STATES INTO SOUTHERN APPALACHIANS...
DESPITE WEAKENING TRENDS TO TROPICAL SYSTEM...LOW-LEVEL SHEAR
PROFILES ALONG/EAST OF TRACK OF CIRCULATION CENTER WILL REMAIN MORE
THAN SUFFICIENT TO MAINTAIN RISK OF TORNADIC ACTIVITY THROUGH THIS
FORECAST PERIOD.  IT APPEARS BEST POTENTIAL FOR TORNADOES AFTER
LANDFALL WILL SHIFT TO THE EAST/SOUTHEAST QUADRANT OF TROPICAL
CYCLONE... WHERE BOUNDARY LAYER WILL BECOME MOST BUOYANT AS DEW
POINTS CLIMB INTO THE MID/UPPER 70S.  INSTABILITY...AND ATTENDANT
RISK FOR TORNADOES...LIKELY WILL BECOME MAXIMIZED DURING THE PEAK
AFTERNOON HEATING ACROSS PARTS OF SOUTHEAST/EAST CENTRAL ALABAMA AND
SOUTHWEST GEORGIA.  THREAT FOR TORNADOES MAY CONTINUE AFTER
DARK...BUT PROBABILITIES SHOULD BEGIN TO DECREASE...AS STRONGER
FORCING SHIFTS INTO PARTS OF NORTHEAST ALABAMA/NORTHERN GEORGIA.

...OHIO VALLEY INTO LOWER GREAT LAKES REGION...
WHILE UPPER TROUGH LIFTS INTO EASTERN CANADA...ASSOCIATED FRONTAL
ZONE WILL TRAIL BACK ACROSS THE LOWER GREAT LAKES REGION INTO THE
LOWER OHIO VALLEY.  THIS FEATURE SHOULD REMAIN FOCUS FOR SCATTERED
THUNDERSTORM ACTIVITY. IN WAKE OF DEPARTING UPPER TROUGH AND AHEAD
OF APPROACHING SUBTROPICAL SHORT WAVE TROUGH/REMNANTS OF IVAN...
STRONGEST LARGE-SCALE FORCING FOR CONVECTIVE DEVELOPMENT MAY BECOME
FOCUSED ACROSS PARTS OF EASTERN OHIO/WESTERN PENNSYLVANIA LATE THIS
AFTERNOON.  GIVEN EXPECTED EVOLUTION OF WEAK TO MODERATELY UNSTABLE
BOUNDARY LAYER ALONG FRONT...FLOW/SHEAR PROFILES ACROSS THIS REGION
MAY REMAIN STRONG ENOUGH TO ENHANCE THUNDERSTORM ACTIVITY.  AN
ISOLATED DAMAGING WIND GUST OR TWO...PERHAPS SOME HAIL...IS POSSIBLE
BEFORE ACTIVITY WEAKENS THIS EVENING.

...SOUTHERN NEW ENGLAND...
SCATTERED THUNDERSTORMS APPEAR POSSIBLE THROUGH EARLY AFTERNOON
...FROM PARTS OF EASTERN LONG ISLAND INTO SOUTHEAST MASSACHUSETTS
AND CAPE COD...BEFORE FLOW ACROSS THIS REGION TAKES ON INCREASINGLY
WESTERLY COMPONENT IN WAKE OF MID-LEVEL TROUGH SHIFTING OFFSHORE.

...PLAINS INTO UPPER MISSISSIPPI VALLEY...
DAYTIME HEATING MAY CONTRIBUTE TO CONVECTIVE DEVELOPMENT IN WARM
ADVECTION REGIME FROM THE EASTERN DAKOTAS INTO NORTHERN MINNESOTA/
PARTS OF NORTHWEST WISCONSIN.  MEANWHILE WARMING MID-LEVEL
ENVIRONMENT...WELL IN ADVANCE OF AMPLIFYING TROUGH OFF THE PACIFIC
NORTHWEST COAST...LIKELY WILL SUPPRESS THUNDERSTORM ACTIVITY ACROSS
THE REMAINDER OF THE PLAINS THROUGH THE DAY. HOWEVER...
TONIGHT...FORCING/ DESTABILIZATION ALONG STRENGTHENING SOUTHERLY
LOW-LEVEL JET MAY SUPPORT WIDELY SCATTERED THUNDERSTORMS ABOVE
NOCTURNAL INVERSION LAYER.

..KERR/BANACOS.. 09/16/2004

...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.