000 FXUS66 KOTX 240335 AFDOTX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPOKANE WA 735 PM PST MON NOV 23 2009 .SYNOPSIS... WEAK PACIFIC WARM FRONT WILL BRING A POSSIBILITY OF VERY LIGHT PRECIPITATION TONIGHT...WITH GENERALLY DRY BUT CLOUDY WEATHER RETURNING TUESDAY AND THROUGH THANKSGIVING DAY. ON FRIDAY A COLD FRONT WILL PASS THROUGH WITH ANOTHER REASONABLE CHANCE OF MOUNTAIN SNOW AND VALLEY RAIN OR SNOW. CONDITIONS WILL REMAIN CLOUDY AND UNSETTLED INTO NEXT WEEKEND. && .DISCUSSION... SATELLITE THIS EVENING SHOWS AN UPPER TROUGH PASSING BY NORTH OF THE INLAND NW ACROSS BRITISH COLUMBIA AND ALBERTA. THE SOUTHERN MOST PORTION OF THIS SYSTEM IS EXPECTED TO DRAG A WEAK WARM FRONT ACROSS THE AREA TONIGHT. A PRECIPITABLE WATER FETCH WITH VALUES OFF THE COAST JUST OVER AN INCH IS AIMED EARLY THIS EVENING AT NORTHERN WASHINGTON. THIS AREA WILL SLOWLY SAG SOUTH TONIGHT WITH THE WARM FRONT PASSAGE. ISENTROPIC LIFT AS THE FRONT PASSES WILL RESULT IN INCREASING PRECIPITATION CHANCES FROM NORTH TO SOUTH. BEST THREAT OF LIGHT PRECIPITATION WILL FALL IN THE OROGRAPHICALLY FAVORED AREAS OF THE CASCADE CREST AND THE MOUNTAINS OF NE WA/N IDAHO WHERE UPSLOPE FLOW WILL OCCUR WHILE DOWNSLOPE FLOW OFF THE CASCADES WILL KEEP POPS ONLY AT 20 PCT FOR WENATCHEE AND MOSES LAKE. CURRENT SATELLITE TRENDS SHOW A SLIGHTLY SLOWER PROGRESSION THAN EARLIER THOUGHT SO POPS WERE TRENDED DOWN THIS EVENING ALONG THE INTERSTATE 90 CORRIDOR FROM SPOKANE TO LOOKOUT PASS. ALSO LOWERED POPS FOR LEWISTON AND WINCHESTER OVERNIGHT BASED ON THE SLOWER PROGRESSION. 1000-850MB THICKNESSES OF 1300-1310DM OVER NE WA/N IDAHO AND 850MB TEMPS OF -2 TO -4C WILL SUPPORT SNOW LEVELS CLOSE TO 2000 FEET. JW && .AVIATION... A WEAK WARM FRONT WILL MOVE INTO NORTHERN WA AND THE ID PANHANDLE TONIGHT RESULTING IN SCT RA/SN SHOWERS. HOWEVER...SOME UNCERTAINTY EXISTS ON WHETHER OR NOT PRECIP...AND SUBSEQUENT MVFR CIGS...WILL REACH THE KGEG-KCOE CORRIDOR LATE TONIGHT. LIGHT UPSLOPE WINDS MAY ALLOW LOW STRATUS TO DEVELOP IN THE KGEG-KCOE AREA AFTER 10Z TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... SPOKANE 33 40 33 40 32 40 / 40 10 0 0 0 10 COEUR D`ALENE 31 39 32 41 32 40 / 50 20 0 0 0 10 PULLMAN 31 41 31 44 33 43 / 50 20 0 0 0 0 LEWISTON 34 47 35 48 35 48 / 20 20 0 0 0 0 COLVILLE 32 41 31 40 31 42 / 60 10 20 10 30 30 SANDPOINT 31 36 29 39 29 40 / 60 30 0 10 10 10 KELLOGG 29 37 31 40 30 40 / 60 40 20 0 0 0 MOSES LAKE 32 46 32 43 31 41 / 20 0 0 0 0 10 WENATCHEE 34 44 34 41 33 39 / 20 10 0 0 10 20 OMAK 31 44 31 43 32 42 / 50 10 10 10 20 30 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...NONE. WA...NONE. && $$