SPC AC 190541
   
   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1141 PM CST TUE JAN 18 2005
   
   VALID 211200Z - 221200Z
   
   ...NO SVR TSTM AREAS FORECAST...
   
   ...SYNOPSIS...
   NORTH AMERICAN SECTOR OF LARGE SCALE PATTERN WILL CONTINUE TO
   FEATURE ERN TROUGH AND WRN RIDGE. EXPECT HEIGHTS TO RISE IN THAT
   RIDGE AS SHORTWAVE TROUGHS -- NOW EVIDENT AROUND 1505 OVER NERN
   PACIFIC AND OVER BAJA CA REGION...EACH EXIT MEAN RIDGE POSITION. 
   EXPECT SRN TROUGH TO DEAMPLIFY AS IT MOVES NEWD ACROSS NRN MEX AND W
   TX...PHASING WITH SEWD-MOVING NRN STREAM PERTURBATION. MAIN MODEL
   DIFFERENCES ATTM REGARD NOT TIMING AS MUCH AS TRACK...PARTICULARLY
   WITH MORE NLY TRACK ACROSS ELP AREA OR MORE SLY TRACK OVER BIG
   BEND...RELATED LARGELY TO PROXIMITY/AMPLITUDE OF NRN STREAM TROUGH. 
   AS NRN STREAM TROUGH DIGS SEWD ACROSS CENTRAL/NRN PLAINS...EXPECT
   SFC CYCLOGENESIS TO SHIFT SEWD FROM NRN HIGH PLAINS ACROSS UPPER MS
   VALLEY...PERHAPS REACHING OH VALLEY BY END OF PERIOD.  TRAILING COLD
   FRONT WILL MOVE SEWD ACROSS MO VALLEY AND MUCH OF CENTRAL/SRN PLAINS
   INTO SW TX.
   
   ...SW TX ACROSS ARKLATEX REGION...
   ISOLATED TSTMS POSSIBLE DURING AFTERNOON ACROSS MOUNTAINS OF NRN
   MEX...AS COLDEST MIDLEVEL AIR PASSES OVER AREAS OF HEATED/ELEVATED
   TERRAIN AND VERY MARGINAL LOW LEVEL MOISTURE.  SOME OF THIS
   HIGH-BASED CONVECTION MAY REACH RIO GRANDE BETWEEN ELP-DRT BEFORE
   DISSIPATING...BUT IS NOT EXPECTED TO POSE SEVERE THREAT BECAUSE OF
   WEAK MOISTURE/CAPE.  AFTER DARK...LOW-MIDLEVEL ASCENT ASSOCIATED
   WITH PHASING TROUGHS MAY SUPPORT MARGINAL ELEVATED CAPE SOMEPLACE
   BETWEEN W-CENTRAL TX AND CENTRAL AR.  BUOYANCY THERE ALSO SHOULD BE
   TOO WEAK TO SUPPORT ORGANIZED SEVERE THREAT...BECAUSE OF WEAK LOW
   LEVEL THETAE IN TRAJECTORIES OF CONTINENTAL-POLAR ORIGIN AND ONLY
   SLIGHT MARINE MODIFICATION.
   
   ..EDWARDS.. 01/19/2005
   
   ...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.
   
   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 1100Z