SPC Dec 21, 2024 1300 UTC Day 1 Convective Outlook

SPC 1300Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0650 AM CST Sat Dec 21 2024

Valid 211300Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms are possible this morning into early
afternoon across parts of coastal Oregon and northern California.

...Coastal OR/northern CA...
A potent mid to upper-level shortwave trough will move ashore the
northern CA/OR coast and continue northeastward into the southern
Canadian Rockies/northern Rockies vicinity through late tonight. 
Weak thunderstorm activity embedded within a warm-air advection rain
shield will continue moving into the coastal range mountains this
morning before outrunning the inland penetration of scant
instability.  The corridor of thunderstorms will probably shift
north along the coast into OR by midday into the early afternoon in
association with the mid-level cold pocket encroaching on the OR
coast.  Elsewhere, quiescent weather or stable conditions will
preclude thunderstorm development over the remainder of the
contiguous United States.

..Smith/Goss.. 12/21/2024

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