High Wind in Washington, December 15 to 16, 2001

NORTHWEST OREGON AND SOUTHWEST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
230 AM PST SAT DEC 15 2001

.SYNOPSIS...WARM FRONT APPROACHING COAST MOVES ASHORE THIS EVENING.
COLD FRONT OVER NORTHERN WASHINGTON TONIGHT STRENGTHENS SUN AS NEXT
LOW PRES APPROACHES.  LOW MOVES INTO BRITISH COLOMBIA SUN EVENING
WITH COLD FRONT SLOWLY PUSHING THROUGH AREA SUN NIGHT MOVING SOUTH
MON MORNING.

.DISCUSSION...
.SHORT TERM...WARM FRONT APPROACHING MOVES ASHORE TONIGHT.  ETA/AVN
CLOSE WITH THIS SYSTEM.  GRADIENTS TIGHTEN ENOUGH TO GIVE LOW END HWW
COAST HEADLANDS LATE TODAY AND TONIGHT WITH WARM FRONT.  THIS
SUPPORTED BY MESOETA WINDS.  FREEZING LEVEL AROUND 2000 FEET AS SHOWN
BY TV TOWER TEMPS.  BEFORE PCPN GETS GOING ANY STICKING SNOW ABOVE 2K
SO WILL END SNOW ADVISORIES FOR LOWER ELEVATIONS.   CASCADES LOOK OK
FOR LOW END ADVISORY TODAY WITH RISING SNOW LEVELS TONIGHT.  AS WARM
FRONT PUSHES THROUGH TONIGHT PCPN BREAKS UP INLAND VALLEYS AND S BUT
CONTINUES N COAST AND INCREASES AS COLD FRONT GETS CLOSER LATE.  850
MB WINDS WITH MODERATE HIGH PW WILL ALLOW SIG PCPN N COAST AREA AND
NORTHERN MOUNTAINS.  MODELS DIVERGE SOME ON SUN WITH AVN BRINGING
SECOND STRONG LOW INTO BRITISH COLUMBIA.  COLD AIR BUILDING MID PAC
ALONG WITH ANOTHER STRONG JET CORE W OF DATELINE FAVOR AVN SOLUTION.
EITHER CASE STRONG GRADIENT DEVELOPS WITH LIKELY MODERATE HIGH WIND
EVENT.  WILL GO WITH WATCH FOR STRONGER WINDS COAST SUN.  COLD FRONT
SLOW TO MOVE THROUGH SUN AND SUN NIGHT WITH VERY FAVORABLE AND STRONG
850 FLOW PCPN BECOMES VERY EFFICIENT.  HEAVY RAIN LIKELY TO CONTINUE
ALONG NORTHERN COAST SUN SPREADING INLAND AND S IN THE AFTERNOON.
FLOODING EVENT VERY POSSIBLE WITH N COAST FIRST LATE TONIGHT AND SUN
AND REST OF AREA POSSIBLE SUN NIGHT AND MON.  FRONT PUSHES THROUGH
MOST OF AREA BY MON MORNING THOUGH S AND FAR E PART SEES MORNING
RAIN.  FRONT CLEARS AREA BY MIDDAY WITH WEAK HIGH PRES PUSHING INTO
AREA.  ANY RESIDUAL SHOWERS MON AFTERNOON MAINLY N COAST AND
MOUNTAINS.

.LONG TERM...EXTENDED MODELS SIMILAR WITH NEXT SYSTEM FOR TUE.
CANADIAN SPLITS NEXT SYSTEM FURTHER OFFSHORE WED/THU WHILE MRF MORE
PROGRESSIVE.  AVN/MRF TRACK COULD MAKE THINGS INTERESTING FOR LOW
LEVEL SNOW.  FOR NOW WILL LUMP WED THROUGH FRI WITH CHANCE OF PCPN.
KOSOVITZ

AST ++++6 PDX 999+5 SLE 999+5 EUG 888+7

.PQR...HIGH WIND WARNING COAST THIS AFTERNOON AND TONIGHT.
       HIGH WIND WATCH COAST SUN.
       GALE WARNING COAST.
       SNOW ADVISORY CASCADES TODAY.
       FLOOD POTENTIAL OUTLOOK...FOR SOUTHWEST WASHINGTON AND
        NORTHWEST OREGON SAT NIGHT THROUGH MON.