Nov 21, 2018 0600 UTC Day 1 Convective Outlook
Updated: Wed Nov 21 05:31:57 UTC 2018 (20181121 1200Z Day 1 shapefile | 20181121 1200Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20181121 1200 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Tornado Graphic
20181121 1200 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20181121 1200 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Large Hail Graphic
20181121 1200 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 210531

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1131 PM CST Tue Nov 20 2018

   Valid 211200Z - 221200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   Isolated thunderstorms are possible today from coastal into central
   California, and across parts of southeast Texas. Severe weather is
   unlikely.

   ...Synopsis and Discussion...
   A progressive upper trough with rapid cooling aloft will affect much
   of the West Coast, with the strongest lift focused from central CA
   into western OR and WA during the day. Moistening and lift combined
   with cold temperatures aloft will result in scattered thunderstorms,
   but weak instability and relatively cool surface temperatures should
   only result in non-severe convection.

   To the east, a weaker, low-latitude trough will move across TX,
   providing lift. Boundary layer temperatures will remain cool and
   stable, but weak warm advection above the surface layer will lead to
   sufficient elevated instability for a few thunderstorms through the
   period, mainly over southeastern TX.

   ..Jewell/Nauslar.. 11/21/2018

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z