Dec 26, 2021 1730 UTC Day 2 Convective Outlook
Updated: Sun Dec 26 17:28:41 UTC 2021 (20211226 1730Z Day 2 shapefile | 20211226 1730Z Day 2 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20211226 1730 UTC Day 2 Outlook Graphic
Day 2 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Tornado Graphic
20211226 1730 UTC Day 2 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 2 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20211226 1730 UTC Day 2 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 2 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Large Hail Graphic
20211226 1730 UTC Day 2 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 2 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 261728

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1128 AM CST Sun Dec 26 2021

   Valid 271200Z - 281200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   Isolated thunderstorms will be possible across parts of the mid and
   upper Ohio Valley vicinity Monday, and across a portion of the
   California coast.

   ...Discussion...
   Longwave troughing will persist over the western half of the U.S.
   Monday, with a number of embedded short-wave perturbations progged
   to rotate/progress through the broader cyclonic flow field.  One
   such short-wave trough -- initially expected to reside over the
   north-central states -- will shift east-northeastward across the
   Upper Mississippi Valley/Upper Great Lakes region through the
   afternoon and evening, before shifting into southern Canada.

   A second of these features is forecast to dig southeastward across
   the West Coast States and Great Basin through the day, before
   turning eastward to continue across the Rockies.  Finally, a third
   vort max is expected to shift southward along the West Coast,
   traversing the Pacific Northwest and northern California vicinity
   through the second half of the period.

   At the surface, a warm front is forecast to lie across the Midwest
   early in the period, while a weakening cold front shifts eastward 
   across the region later in the day Monday.  Showers -- and a few
   elevated thunderstorms -- are expected through the day north of the
   warm front, but expect CAPE to remain too minimal for any
   appreciable severe-caliber hail potential.  Meanwhile, meager
   instability at best within the warm sector ahead of the cold front
   should preclude any severe potential.

   In the West, showers are expected across portions of
   Oregon/Idaho/California/Nevada and vicinity.  While a lightning
   flash or two will be possible across this region, the only area
   where thunder potential appears substantial enough to warrant a 10%
   area is along portions of the central and southern California coast.

   Elsewhere, thunderstorms are not expected.

   ..Goss.. 12/26/2021

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   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0700Z