FXUS66 KOTX 260525
AFDOTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
925 PM PST WED NOV 25 2009
.SYNOPSIS...
WEAK HIGH PRESSURE WILL KEEP THE INLAND NORTHWEST MAINLY DRY
WEDNESDAY NIGHT AND THANKSGIVING DAY. THE EXCEPTION WILL BE THE
CASCADES AND OKANOGAN VALLEY WHERE THERE WILL BE A CHANCE OF LIGHT
RAIN AND HIGH MOUNTAIN SNOW. THE NEXT STORM SYSTEM WILL BRING
MOUNTAIN SNOW AND VALLEY RAIN TO MOST OF THE REGION THURSDAY NIGHT
AND FRIDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT.
&&
.DISCUSSION...
UPDATE FOR TONIGHT...INFRARED SATELLITE DEPICTIONS CONTINUE TO
SHOW HIGH CLOUDS STREAMING INTO THE WESTERN TWO-THIRDS OF THE
FORECAST AREA THIS EVENING. AMONGST THESE MIDDLE AND HIGH
CLOUDS...FROM ABOUT THE UPPER COLUMBIA BASIN EASTWARD...A HANDFUL
OF BREAKS HAVE BEEN NOTED AS THE EVENING HAS PROGRESSED. UNDER THE
THICKER OVERCAST FARTHER WEST...STATUS QUO LOOKS TO BE THE STORY
FOR THE REST OF THE NIGHT. THIS WILL INCLUDE THE
WENATCHEE...OMAK...AND MOSES LAKE AREAS. INSUFFICIENT RADIATION
THROUGH EITHER THE STRATUS PRESENT ACROSS THE EAST
SLOPES...WENATCHEE...AND OMAK AREAS OR THROUGH THE MIDDLE AND HIGH
CLOUDS NEAR MOSES LAKE IS LIKELY TO PRECLUDE MUCH IN THE WAY OF
FOG DEVELOPMENT TONIGHT...MUCH THE SAME AS LAST NIGHT.
HOWEVER...AREAS WITH STRATUS WILL LIKELY KEEP IT ALL NIGHT.
FARTHER EAST...NEAR SPOKANE...COEUR D'ALENE AND THE NORTHEASTERN
VALLEYS OF WASHINGTON...THE FAVORED SPOTS FOR FOG FORMATION ARE
LIKELY TO SEE SOME PATCHES OF DENSE FOG AGAIN TOWARD MORNING. WITH
A FEW HOLES IN THE MID-CLOUDS...RADIATION FOG SHOULD DEVELOP AGAIN
OVER THE WEST PLAINS...SHELTERED MOUNTAIN VALLEYS...AND EVEN IN
SOME SPOTS IN THE U.S. 95 CORRIDOR NORTH OF COEUR D'ALENE. FARTHER
SOUTH ON THE PALOUSE...THE CONTINUED PRESSURE GRADIENT DRIVEN
EASTERLY DOWNSLOPE FLOW OFF THE IDAHO PANHANDLE MOUNTAINS SHOULD
CONTINUE TO PRECLUDE FOG DEVELOPMENT THROUGH THE NIGHTTIME HOURS.
ALSO...A LOOK AT THE 18Z NAM/GFS AND 00Z NAM INDICATES A VERY SLOW
PROGRESSION OF THE PRECIPITATION FIELD OVER WESTERN WASHINGTON AT
THE MOMENT INTO THE EASTERN HALF OF THE STATE. IN GENERAL...THE
MODELS KEEP ALMOST ALL OF THE MEASURABLE PRECIPITATION IN WESTERN
WASHINGTON THROUGH AT LEAST 18Z ON THANKSGIVING DAY. AS A
RESULT...POPS HAVE BEEN HAULED BACK THROUGH THAT TIME...WITH
RAINFALL CHANCES NOT REACHING SPOKANE UNTIL LATER IN THE AFTERNOON
OR EVENING OF THANKSGIVING. /FRIES
&&
.AVIATION...
FOG HAS ALREADY FORMED AND WILL PERSIST INTO THE LATE MORNING HOURS
OF THANKSGIVING AROUND KGEG AND KCOE...WITH THE FOG EXTENDING OVER
KSFF AS STRATUS. MOST OTHER SITES WILL SEE STRATUS CONTINUE THROUGH
THE NEXT 24 HOURS AS THE NEXT SYSTEM APPROACHES FROM THE WEST AFTER
26/21Z. -RA WILL MOVE THROUGH KEAT AND KMWH BY THE AFTERNOON OF
THURSDAY...AND MOVE EASTWARD FROM THERE AFTER THAT TIME. FOG WILL BE
SLOW TO BURN DUE TO INCOMING MID-CLOUDS...SO EXPECT VLIFR CONDITIONS
TO PERSIST IN SPOTS WITH FOG THROUGH AT LEAST 26/19Z. /FRIES
&&
.PRELIMINARY POINT TEMPS/POPS...
SPOKANE 34 42 36 41 30 36 / 0 0 50 50 20 20
COEUR D'ALENE 34 43 35 41 31 38 / 0 0 50 80 40 20
PULLMAN 35 45 36 40 30 37 / 0 0 30 70 40 30
LEWISTON 38 49 39 47 34 41 / 0 0 30 50 30 30
COLVILLE 36 41 34 42 31 39 / 10 10 60 60 20 10
SANDPOINT 31 37 35 38 31 34 / 0 0 50 80 40 30
KELLOGG 34 41 35 37 29 33 / 0 0 40 90 50 50
MOSES LAKE 31 45 34 46 29 42 / 0 10 40 20 10 10
WENATCHEE 37 44 34 45 33 43 / 0 10 40 10 10 10
OMAK 36 44 33 44 28 42 / 10 30 60 30 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
WA...NONE.
&&
$$
