FXUS66 KOTX 151421
AFDOTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
621 AM PST TUE DEC 15 2009
.SYNOPSIS...
A SECOND ROUND OF WINTRY PRECIPITATION WILL LIKELY DEVELOP LATE
THIS AFTERNOON AND CONTINUE THROUGH TONIGHT. PORTIONS OF CENTRAL
AND NORTHEAST WASHINGTON...AS WELL AS THE NORTHERN IDAHO PANHANDLE
WILL RECEIVE ADDITIONAL ACCUMULATIONS TONIGHT. THE ARRIVAL OF A
MILDER AIR MASS TODAY INTO TOMORROW WILL PUSH TEMPERATURES ABOVE
FREEZING FOR MANY OF THE LOWER ELEVATIONS. SNOW WILL CHANGE TO
RAIN IN THE VALLEYS BY WEDNESDAY AND THE MILDER CONDITIONS ARE
EXPECTED TO CONTINUE THROUGH THE END OF THE WEEK.
&&
.DISCUSSION...
WINTER STORM WARNINGS HAVE BEEN DOWNGRADED TO WINTER WEATHER
ADVISORIES FOR THE OMAK...WENATCHEE...WATERVILLE...
REPUBLIC...MOSES LAKE...AND RITZVILLE AREAS. THERE SHOULD BE A
BREAK IN SIGNIFICANT ACCUMULATIONS FOR THE AFOREMENTIONED AREAS THIS
MORNING. REDEVELOPMENT OF SNOW IS EXPECTED BY EARLY AFTERNOON IN
CENTRAL AND NORTH CENTRAL WASHINGTON. THE NEXT WAVE ON WATER VAPOR
IMAGERY IS STILL WELL OFF THE COAST OF OREGON. THE 06Z RUNS OF THE
NAM AND GFS HAVE COME INTO GOOD AGREEMENT WITH THE REDEVELOPMENT
OF WARM ADVECTION PRECIPITATION OVER THE BASIN...OKANOGAN
HIGHLANDS/VALLEY...AND WENATCHEE AREA THIS AFTERNOON THROUGH THIS
EVENING. THERMAL PROFILES FROM THE GFS APPEAR TO BE HANDLING WARM
AIR ALOFT (850MB) BETTER IN THE LOWER COLUMBIA BASIN. BY LATE
AFTERNOON INTO THE EVENING...GFS SOUNDINGS SUGGEST THE POTENTIAL
FOR A WEDGE OF LIGHT FREEZING RAIN IN THE MOSES LAKE...EPHRATA...
AND WILBUR AREAS.
A BREAK IN ACCUMULATING SNOW IS ALSO LIKELY IN THE SPOKANE...COEUR
D'ALENE...AND SANDPOINT AREAS THIS MORNING. RADAR REFLECTIVITIES
AS OF 14Z...SHOW A SIGNIFICANT DECREASE THE SNOWFALL RATES OVER
THE EASTERN THIRD OF WASHINGTON. ADDITIONAL ACCUMULATIONS THIS
MORNING FOR SPOKANE...COEUR D'ALENE...AND PULLMAN SHOULD BE
LIMITED TO AN INCH OR LESS. REDEVELOPMENT IS EXPECTED BY MID
AFTERNOON. WARM ADVECTION THIS AFTERNOON WILL MAKE SNOW LEVELS
TRICKY. SNOW LEVELS THIS AFTERNOON SHOULD BE RISING ABOVE 3000
FEET OVER THE PALOUSE...NEGATING MUCH LOW ELEVATION ACCUMULATION.
DOWNTOWN SPOKANE MAY EVEN STRUGGLE TO GET ADDITIONAL ACCUMULATIONS
THIS AFTERNOON/EVENING WITH SNOW LEVELS CREEPING UP TO 2000-2500
FEET. THE DAY SHIFT MAY ELECT TO DOWNGRADE THE WINTER STORM
WARNING FOR SPOKANE/COEUR D'ALENE TO AN ADVISORY IF THIS SCENARIO
PANS OUT. /GKOCH
&&
.AVIATION...
WIDESPREAD LOW CEILINGS ARE EXPECTED THROUGH AT LEAST WEDNESDAY
MORNING OVER THE MAJORITY OF EASTERN WASHINGTON AND NORTHERN
IDAHO. MOST LOCATIONS WILL EXPERIENCE CEILINGS BELOW 2500 FEET FOR
THE NEXT 24 HOURS. ANOTHER ROUND OF RAIN AND SNOW WILL DEVELOP
THIS AFTERNOON AND THIS EVENING. DROPPING VISIBILITIES BELOW 2
MILES IN WENATCHEE...SPOKANE...AND COEUR D'ALENE. FREEZING RAIN
MAY BE A PROBLEM TONIGHT IN MOSES LAKE. /GKOCH
&&
.PRELIMINARY POINT TEMPS/POPS...
SPOKANE 32 31 36 29 37 30 / 90 100 50 60 20 20
COEUR D'ALENE 32 32 37 30 37 31 / 100 100 60 70 30 20
PULLMAN 35 34 40 32 39 33 / 100 90 50 50 20 20
LEWISTON 42 38 44 34 43 35 / 80 70 30 40 20 10
COLVILLE 30 29 36 31 37 32 / 70 100 70 70 20 20
SANDPOINT 28 28 32 27 33 28 / 100 100 80 80 40 20
KELLOGG 31 31 38 30 36 32 / 100 100 90 80 60 30
MOSES LAKE 30 29 36 27 37 29 / 40 80 20 40 20 20
WENATCHEE 27 26 32 26 34 31 / 60 80 20 30 20 20
OMAK 25 25 30 25 36 30 / 20 100 50 40 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR IDAHO
PALOUSE.
WINTER STORM WARNING UNTIL 4 AM PST WEDNESDAY FOR NORTHERN
PANHANDLE.
WINTER STORM WARNING UNTIL 4 PM PST THIS AFTERNOON FOR COEUR
D'ALENE AREA.
WINTER STORM WARNING UNTIL 4 AM PST WEDNESDAY FOR CENTRAL
PANHANDLE MOUNTAINS.
WA...WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM PST
WEDNESDAY FOR OKANOGAN HIGHLANDS...OKANOGAN VALLEY...
WENATCHEE AREA.
WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
NORTHEAST BLUE MOUNTAINS.
WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
WASHINGTON PALOUSE.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM PST
WEDNESDAY FOR MOSES LAKE AREA...UPPER COLUMBIA BASIN...
WATERVILLE PLATEAU.
WINTER STORM WARNING UNTIL 4 AM PST WEDNESDAY FOR NORTHEAST
MOUNTAINS.
WINTER STORM WARNING UNTIL 4 PM PST THIS AFTERNOON FOR SPOKANE
AREA.
WINTER STORM WARNING UNTIL 10 PM PST THIS EVENING FOR EAST
SLOPES NORTHERN CASCADES.
&&
$$
