[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 260555
SWODY1
SPC AC 260553

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1153 PM CST FRI FEB 25 2005

VALID 261200Z - 271200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM DRT SEP PRX ELD 45
ESE LUL 15 SSE AQQ.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 WSW FHU GBN 50 WSW
EED BIH 35 E SAC SVE LOL U31 35 NW MLF PUC GJT 10 NE 4SL 4CR CNM 65
SSW P07.

...NO SVR TSTM AREAS FORECAST...

BUILDING UPPER RIDGE IS ALREADY EVIDENT OFF THE PACIFIC NORTHWEST/
BRITISH COLUMBIA COAST...AND RE-AMPLIFICATION OF NORTHERN BRANCH
RIDGE WILL CONTINUE THROUGH THIS FORECAST PERIOD...AS DOWNSTREAM
SHORT WAVE TROUGH CLEARS THE CANADIAN ROCKIES. LATTER FEATURE IS
PROGGED TO DIG SOUTH SOUTHEASTWARD INTO THE VICINITY OF THE CENTRAL
CANADIAN/U.S. BORDER BY 12Z SUNDAY.  AS THIS OCCURS...MODELS SUGGEST
BROADER SCALE TROUGH IN SOUTHERN BRANCH OF POLAR WESTERLIES AND
SUBTROPICAL WESTERLIES WILL FINALLY DEVELOP EASTWARD OUT OF THE
SOUTHWESTERN U.S./NORTHERN MEXICAN PLATEAU INTO THE SOUTH CENTRAL
STATES/WESTERN GULF OF MEXICO.

INTERACTING IMPULSES EMBEDDED WITHIN SOUTHERN/SUBTROPICAL STREAMS
APPEAR TO BE A SIGNIFICANT SOURCE OF MODEL VARIABILITY...
PARTICULARLY WITH REGARD TO SURFACE DEVELOPMENTS OVER THE WESTERN
GULF OF MEXICO...AND AREAS NEAR THE WESTERN GULF COAST.  LATEST NAM
RUN FORECASTS STRONGER SURFACE LOW DEVELOPMENT ALONG TEXAS COASTAL
AREAS LATER TODAY/TONIGHT THAN THE GFS.  THIS APPEARS TO OCCUR ON
NORTHERN EDGE OF INVERTED TROUGH EXTENDING NORTHWARD FROM PRIMARY
SURFACE CYCLONE...WHICH SHOULD FORM ALONG SURFACE BAROCLINIC ZONE
EXTENDING ACROSS THE SOUTH CENTRAL/SOUTHWESTERN GULF OF MEXICO.

EVEN IF NAM VERIFIES CLOSER THAN GFS...CURRENT STATE OF BOUNDARY
LAYER OVER THE WESTERN GULF OF MEXICO SUGGESTS MINIMAL SEVERE THREAT
DURING THIS FORECAST PERIOD.  DEW POINTS ARE CURRENTLY IN THE
LOWER/MID 50S ACROSS THIS REGION...AND SUBSTANTIAL MODIFICATION DOES
NOT APPEAR LIKELY TO OCCUR EVEN IN COASTAL WATERS OF TEXAS/LOUISIANA
THROUGH AT LEAST EARLY SUNDAY.

...TEXAS/LOUISIANA...
MID/UPPER MOISTURE ADVECTION OFF THE SUBTROPICAL PACIFIC...ACROSS
THE MEXICAN PLATEAU...INTO THE LOWER RIO GRANDE VALLEY IS ONGOING. 
AS EXIT REGION OF APPROACHING MID-LEVEL JET STREAK APPROACHES THE
LOWER RIO GRANDE VALLEY BY DAYBREAK...LAPSE RATES ABOVE STABLE
SURFACE-BASED LAYER MAY STEEPEN SUFFICIENTLY FOR THUNDERSTORM
ACTIVITY INTO PARTS OF SOUTH CENTRAL/DEEP SOUTH TEXAS. 

DEVELOPING RAIN SHIELD...WITH POSSIBLE CONTINUING EMBEDDED
THUNDERSTORMS...IS THEN EXPECTED TO SLOWLY SPREAD NORTHEASTWARD
TOWARD THE LOWER MISSISSIPPI VALLEY.  IN THE WAKE OF THIS
ACTIVITY...ADDITIONAL SCATTERED THUNDERSTORMS APPEAR POSSIBLE IN
STRONGER LOW-LEVEL WARM ADVECTION REGIME NEAR TEXAS COASTAL AREAS. 
THIS MAY OCCUR LATER TODAY/TONIGHT AS SOMEWHAT BETTER LOW-LEVEL
MOISTURE RETURNS FROM THE SOUTHWESTERN GULF...ABOVE FRONTAL
INVERSION.

...GREAT BASIN/SOUTHERN PLATEAU/SOUTHERN ROCKIES...
BEFORE MID-LEVEL COLD POOL SHIFTS EASTWARD...SCATTERED THUNDERSTORMS
APPEAR LIKELY TODAY ACROSS THE HIGHER TERRAIN...PRIMARILY IN
RESPONSE TO DAYTIME HEATING/OROGRAPHIC FORCING.

..KERR.. 02/26/2005

...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.