SPC AC 080801

   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0201 AM CST TUE DEC 08 2015

   VALID 101200Z - 111200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SUMMARY...
   A FEW THUNDERSTORMS WILL BE POSSIBLE THURSDAY ACROSS COASTAL REGIONS
   OF WASHINGTON AND OREGON...AND SOUTHWARD INTO PORTIONS OF NORTHERN
   AND CENTRAL CALIFORNIA.

   ...SYNOPSIS...
   A LOW-AMPLITUDE MIDLEVEL SHORTWAVE TROUGH WILL REMAIN PROGRESSIVE ON
   D3...AS IT ADVANCES TO THE EAST/NORTHEAST FROM THE NORTHERN PLAINS
   AND MID MO VALLEY AT 12Z THURSDAY...MOVING INTO THE GREAT LAKES AND
   OH VALLEY.  MEANWHILE...OF GREATER IMPORTANCE FOR TSTM POTENTIAL
   DURING D3...A LARGE PACIFIC TROUGH EXPECTED TO BE MOVING ASHORE THE
   PACIFIC NORTHWEST AT THE START OF D3 WILL UNDERGO FURTHER
   AMPLIFICATION AS IT ADVANCES FARTHER INLAND ACROSS THE WESTERN
   STATES.  STRONG MID- TO UPPER-LEVEL WINDS /100+ KT AT 500-MB/ WILL
   BE SUSTAINED THROUGH THE SOUTHWEST PERIPHERY INTO THE BASE OF THIS
   LARGE-SCALE TROUGH...WITH DOWNSTREAM FLOW BECOMING SOUTHWESTERLY
   FROM THE SOUTHWEST TO THE NORTHEAST STATES.

   ...COASTAL WA/ORE TO NORTHERN AND CENTRAL CA...
   COLD 500-MB TEMPERATURES /-25 TO -30 C/ SPREADING EAST AND SOUTHEAST
   ATTENDANT TO THE AMPLIFYING WESTERN U.S. LARGE-SCALE TROUGH WILL
   SUPPORT STEEPENING LOWER- TO MID-TROPOSPHERIC LAPSE RATES OF 7.5-8.0
   C/KM THURSDAY AND THURSDAY NIGHT.  THIS COMBINED WITH PRECIPITABLE
   WATER AROUND 0.5 INCHES WILL CONTRIBUTE TO MUCAPE OF 100-450 J/KG. 
   FORCING FOR ASCENT IN THE EXIT REGION OF A 100+ KT 500-MB JET SHOULD
   PROVE SUFFICIENT FOR A FEW TSTMS DEVELOPING FROM NORTH TO SOUTH AS
   THE TROUGH AMPLIFIES.  SOME OF THE CONVECTION COULD POSE A LOW RISK
   FOR SMALL HAIL.

   ..PETERS.. 12/08/2015

   CLICK TO GET WUUS03 PTSDY3 PRODUCT

   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0830Z