SPC AC 111608

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1008 AM CST Tue Dec 11 2018

   Valid 111630Z - 121200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   Isolated thunderstorms will be possible late this evening through
   tonight along the Pacific Northwest coast.

   ...Synopsis...
   Relatively cool/dry air in the low levels will dominate the majority
   of the CONUS, with no threat for thunderstorms.  A southern stream
   shortwave trough will move over northern Baja through tonight,
   though any substantial low-midlevel moistening and related threat
   for deep convection will remain south of the AZ border.  A northern
   stream shortwave trough over the southeast Gulf of AK will progress
   inland over WA/northern OR this evening into tonight.  Steep
   low-midlevel lapse rates with the midlevel thermal trough, in the
   post-frontal onshore flow regime, will support weak surface-based
   buoyancy (SBCAPE generally 100-300 J/kg) and an attendant threat for
   isolated, low-topped thunderstorms late this evening into tonight.

   ..Thompson.. 12/11/2018

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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z