SPC Day 2 Thunderstorm Outlook Issued 0830Z 20040115

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ZCZC SPCSWODY2 ALL
ACUS02 KWNS 150829
SPC AC 150829

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0229 AM CST THU JAN 15 2004

VALID 161200Z - 171200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 SSE ELP GDP 40 ENE
HOB CDS 50 S PNC 15 SW JLN 50 SE HRO 20 ESE PBF 25 W HEZ 10 WSW HUM.

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
SRN STREAM JET WILL BECOME AN INCREASINGLY IMPORTANT FACTOR IN
DETERMINING SENSIBLE WEATHER OVER THE S CNTRL U.S. THIS PERIOD AS
INTENSE POLAR VORT EXPECTED TO EVOLVE OFF THE NEW ENGLAND COAST
LATER TODAY LIFTS NE TOWARD THE CANADIAN MARITIME AND WEAKENS. 
SATELLITE/UPPER AIR DATA CURRENTLY DEPICT A COMPLEX SITUATION IN THE
SRN STREAM...WITH SEVERAL IMPULSES APPARENT OFF BOTH THE CA AND BAJA
CA COASTS...AS WELL AS OVER AZ AND NW MEXICO.  THE DATA DO SEEM
SUPPORTIVE OF LATEST GFS/ECMWF FORECASTS DEPICTING DEVELOPMENT OF A
CLOSED LOW INVOF CNTRL BAJA CA BY 12Z FRIDAY.  THIS FEATURE SHOULD
CONTINUE E INTO N CNTRL MEXICO BY THE END OF THE PERIOD.

AT LOWER LEVELS...LIGHT S/SELY FLOW EXPECTED TO PERSIST ACROSS SRN
AND ERN TX THROUGH FRIDAY.  THIS SHOULD ESTABLISH/MAINTAIN SURFACE
DEWPOINTS IN THE LOW TO MID 60S ACROSS THE REGION.  A WEAK SURFACE
WAVE SHOULD GRADUALLY EVOLVE OVER THE RED RIVER VLY AS A COLD FRONT
ASSOCIATED WITH WEAK IMPULSES OF MORE NRN ORIGIN SETTLES S ACROSS
THE CNTRL/SRN PLNS.

...SRN/SERN TX...
SCATTERED EMBEDDED THUNDERSTORMS WILL LIKELY DEVELOP OVER PARTS OF
SRN/CNTRL AND SERN TX ON FRIDAY AS LOW LEVEL WARM ADVECTION
INTENSIFIES DOWNSTREAM FROM UPPER TROUGH CROSSING NW/N CNTRL MEXICO.
 WITH THE UPPER SYSTEM TRACKING FARTHER S AND MORE SLOWLY THAN
PREVIOUSLY FORECAST...DEEP SHEAR WILL PROBABLY REMAIN AOB 30 KTS
ACROSS THE REGION THROUGH THE DAY. SWD TRACK WILL ALSO TEND TO
DIMINISH MID LEVEL LAPSE RATES.  AT THE SAME TIME...WIDESPREAD
CLOUDS WILL LIKELY INHIBIT LOW LEVEL DESTABILIZATION.  TAKEN
TOGETHER...THIS SUGGESTS THAT SEVERE THREAT SHOULD REMAIN LIMITED
THROUGH THE DAY.

DEEP SHEAR WILL INCREASE LATE IN THE PERIOD /AFTER 06Z SATURDAY/
ACROSS FAR S TX AND ALONG THE MIDDLE TX GULF CST EWD INTO THE WRN
GULF AS STRONGER FLOW ASSOCIATED WITH APPROACHING UPPER TROUGH
BEGINS TO AFFECT REGION.  THIS MAY RESULT IN INTENSIFICATION OF
EXISTING CONVECTION AND/OR THE DEVELOPMENT OF NEW STORMS OVER THE
REGION AT THAT TIME.  PARTS OF COASTAL TX WILL HAVE TO BE MONITORED
FOR POSSIBLE UPGRADE TO SLIGHT RISK IF SUFFICIENT DESTABILIZATION IS
ABLE TO OCCUR BEFORE LOW LEVEL CONVERGENCE FIELD SHIFTS OFFSHORE.

...SW/S CNTRL TX/BIG BEND REGION...
A FEW AFTERNOON/EVENING THUNDERSTORMS MAY FORM OVER THE HIGHER
TERRAIN OF SW TX AND THE BIG BEND REGION ON FRIDAY IF LOW CLOUDS
BREAK...ALLOWING FOR LOW LEVEL DESTABILIZATION IN REGION CLOSER TO
APPROACHING UPPER TROUGH.  WITH WEAK CONVERGENCE LIKELY TO BE
PRESENT AT LOWER LEVELS AND MODEST DEEP SHEAR SUPPORTIVE OF
SUSTAINED MULTICELLS...SOME OF THIS ACTIVITY COULD YIELD HAIL AS MID
LEVEL TEMPERATURES COOL TO AROUND MINUS 16-18C.

..CORFIDI.. 01/15/2004

...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.

$$