SPC AC 240514
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1114 PM CST Tue Jan 23 2018
Valid 241200Z - 251200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
Isolated thunderstorms will be possible across coastal areas of the
Pacific Northwest through tonight.
The western upper ridge will progress eastward across the Rockies to
the Plains this period, while an upper trough moves onshore the
Pacific coast. As the trough moves towards the coast, an intense jet
streak will overspread coastal OR and CA and midlevel cooling will
occur. Concurrently at the surface, a weak cold front will move
inland over the Pacific Northwest and northern CA and modest
steepening of low to midlevel lapse rates will occur. Forecast
soundings indicate very weak, albeit adequate, instability for
isolated lightning strikes along the coast and perhaps into portions
of the Willamette Valley. Of note, background flow will be strong as
this system moves inland and may produce damaging winds. However,
these winds will not be convective in nature, thus precluding the
need for severe probs.
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z