[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 191635
SWODY1
SPC AC 191633

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1133 AM CDT THU AUG 19 2004

VALID 191630Z - 201200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 SW
MGW 45 W UNI 25 N LUK 30 NW DAY 40 NNW DAY 35 S FDY 30 S YNG PSB 30
NW CXY 10 WNW CXY 20 SSE HGR 20 SW MGW.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 W CTY AYS 50 WNW
SAV AGS AHN ATL 25 NE GAD 45 NE HSV 40 NW CSV 40 S LEX LEX 35 NE SDF
OWB PAH JBR GWO LUL 30 SSW PNS ...CONT... MFE ALI COT 70 W COT
...CONT... 70 S GBN 20 NNW YUM 40 W BLH 60 E DAG 40 SSW DRA 65 N DRA
TPH 60 ESE BIH 50 N NID 60 S BIH 45 SSW TVL MHS 40 NE BLI ...CONT...
45 NW CTB GTF 3HT BIL AIA 35 NNW IML 35 W EHA EHA GCK RSL CNK FNB 25
S DTW.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS CENTRAL OH AND SW PA
THIS AFTERNOON/EVENING....

...OH VALLEY TO NEW ENGLAND AREA...
A STRONG MID LEVEL SHORTWAVE TROUGH IS LIFTING ENEWD OVER
QUEBEC...AS PART OF A LARGER CYCLONIC VORTEX CENTERED OVER ONTARIO. 
THE BELT OF STRONGER /AOA 50 KT/ MID LEVEL FLOW EXTENDS IN A
CYCLONIC ARC OVER THE GREAT LAKES AND SAINT LAWRENCE VALLEY.  AT THE
SURFACE...A COLD FRONT IS MOVING SLOWLY EWD/SEWD ACROSS LAKES
ONTARIO/ERIE TOWARD WRN NY.  THIS FRONT EXTENDS WWD ACROSS NRN
OH/INDIANA TO CENTRAL IL/MO...AND THIS PORTION OF THE FRONT SHOULD
BECOME QUASI-STATIONARY THIS AFTERNOON INTO TONIGHT.

THE COLD FRONT IS EXPECTED TO SLOW AND WEAKEN ACROSS NY/NRN NEW
ENGLAND THIS AFTERNOON INTO TONIGHT.  WHILE THIS FRONT WILL PROVIDE
A FOCUS FOR THUNDERSTORM DEVELOPMENT ACROSS UPSTATE NY AND NRN NEW
ENGLAND THROUGH THIS EVENING...INSTABILITY IS RELATIVELY WEAK ACROSS
THIS AREA AND ONLY A SPORADIC/MARGINAL WIND DAMAGE THREAT IS
ANTICIPATED.  FARTHER S...SOMEWHAT RICHER BOUNDARY LAYER MOISTURE
EXISTS ACROSS SRN NEW ENGLAND AND THE HUDSON VALLEY.  HOWEVER...12Z
SOUNDINGS SHOWED POOR LOW-MID LEVEL LAPSE RATES...AND SATELLITE
IMAGERY CONTINUES TO SHOW A LARGE AREA OF CLOUDS OVERSPREADING MUCH
OF NEW ENGLAND WHICH WILL SLOW DAYTIME HEATING.  THE AREA FROM ERN
PA TO SRN NEW ENGLAND IS ALSO ALONG THE SRN FRINGE OF THE STRONGER
MID LEVEL FLOW...AND WINDS WILL NOT INCREASE THIS AFTERNOON AS WEAK
MID LEVEL HEIGHT RISES ARE EXPECTED OVER THIS AREA.  GIVEN NO
OBVIOUS FOCUS FOR THUNDERSTORM DEVELOPMENT AND THE MEDIOCRE
INSTABILITY/WIND FIELDS...ANY WIND DAMAGE THREAT SHOULD REMAIN BOTH
ISOLATED AND MARGINAL.

GREATER INSTABILITY IS EXPECTED THIS AFTERNOON ALONG THE STALLED E-W
FRONT FROM CENTRAL OH INTO SW/S CENTRAL PA...WHERE BREAKS IN THE
CLOUDS WILL ALLOW STRONG SURFACE HEATING.  THE COMBINATION OF MLCAPE
VALUES APPROACHING 1500 J/KG AND 35-45 KT MEAN WINDS IN THE LOWEST 6
KM MAY SUPPORT A FEW SHORT LINE SEGMENTS CAPABLE OF PRODUCING
DAMAGING WINDS/MARGINALLY SEVERE HAIL...MAINLY THIS AFTERNOON AND
EARLY THIS EVENING. 

...TX AREA...
WATER VAPOR IMAGERY SHOWS A PRONOUNCED SHORTWAVE TROUGH LIFTING NEWD
FROM N TX INTO SRN OK...WITH THE NEXT UPSTREAM WAVE LOCATED WELL TO
THE W OVER CENTRAL AZ. A LARGE CLUSTER OF THUNDERSTORMS IS ONGOING
ACROSS N TX IN ASSOCIATION WITH THE MID LEVEL WAVE. ADDITIONAL STORM
DEVELOPMENT IS LIKELY ALONG THE SRN AND ERN FLANK OF THIS CLUSTER
WHERE SURFACE HEATING AND MID 70 BOUNDARY LAYER DEWPOINTS SUPPORT
MLCAPE VALUES NEAR 3000 J/KG THIS AFTERNOON.  THE STRONGEST STORMS
MAY PRODUCE ISOLATED DOWNBURST WINDS ACROSS NE TX...WHILE MARGINAL
SUPERCELL TYPE STORMS MAY OCCUR ALONG THE CENTRAL TX PORTION OF THE
OUTFLOW BOUNDARY LATER THIS AFTERNOON WHERE VERTICAL SHEAR WILL BE
SOMEWHAT ENHANCED.  THE MARGINAL SUPERCELL THREAT WILL ALSO EXIST
ACROSS W/SW TX...BUT THE LACK OF LARGE SCALE SUPPORT FOR ASCENT
SUGGESTS THAT STORM COVERAGE WILL REMAIN ISOLATED ACROSS THIS AREA
UNTIL LATER TONIGHT AS THE AZ WAVE APPROACHES.

..THOMPSON/EDWARDS.. 08/19/2004

...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.