Storm Prediction Center Dec 25, 2021 0600 UTC Day 1 Convective Outlook

Dec 25, 2021 0600 UTC Day 1 Convective Outlook

Updated: Sat Dec 25 05:42:33 UTC 2021 (

)

Probabilistic to Categorical Outlook Conversion Table

Categorical Graphic

Day 1 Risk	Area (sq. mi.)	Area Pop.	Some Larger Population Centers in Risk Area
No Risk Areas Forecast

Probabilistic Tornado Graphic

20211225 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

20211225 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

20211225 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 250542

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1142 PM CST Fri Dec 24 2021

   Valid 251200Z - 261200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   Isolated thunderstorms will be possible along the Pacific Coast and
   in portions of the Ohio Valley today.

   ...Synopsis...
   A progressive upper-level flow pattern will exist across a majority
   of the CONUS on Saturday morning. Along the West Coast, an
   upper-level trough will intensify and amplify during the day. At the
   surface, a weak cold front will progress southeastward across
   California. Another cold front, initially across the Upper Midwest,
   will make modest progress to the south in the wake of a
   low-amplitude shortwave trough.

   ...Ohio Valley...
   Warm and moist advection continues ahead of a fast-moving,
   low-amplitude shortwave trough currently in the Mid-Missouri Valley.
   Temperatures in parts of Illinois and Indiana have risen into the
   low 60s F with mid/upper 50s F into Ohio. Given upstream dewpoints
   across the Mid-Mississippi Valley in the mid/upper 50s F, it seems
   plausible that areas of at least mid 50s F dewpoints will exist
   tomorrow morning. Convective showers and isolated thunderstorms
   could produce gusty winds given the moderate winds in the lowest 2
   km. The limiting factors will be weak buoyancy and a tendency for
   storms to remain rooted slightly above the surface.

   ...California...
   A weak surface trough/front will progress southeastward through
   central and southern California. Despite very cold temperatures
   aloft, limited moisture and surface heating will keep buoyancy
   rather weak. Some convection may deepen sufficiently to produce
   lightning. The stronger activity could also produce gusty winds and
   small hail. Given the thermodynamic limitations and modest low-level
   winds, organized severe potential continues to appear low.

   ..Wendt/Moore.. 12/25/2021

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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