FXUS66 KOTX 101213
AFDOTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
415 AM PST THU DEC 10 2009
.SYNOPSIS...
MAINLY DRY AND COLD CONDITIONS WILL CONTINUE THROUGH THE REST OF
THE WORK WEEK...WITH A SLOW WARMING TREND EXPECTED. DESPITE THE
WARMING...TEMPERATURES WILL REMAIN WELL BELOW NORMAL FOR THIS TIME
OF YEAR. A MOIST JET STREAM WILL APPROACH THE OREGON-WASHINGTON
BORDER THIS WEEKEND RESULTING IN A CHANCE OF LIGHT TO MODERATE SNOW
EXTENDING FROM THE BLUE MOUNTAINS TO THE CENTRAL IDAHO PANHANDLE.
THE JET WILL CONTINUE TO SURGE NORTH INTO EARLY NEXT WEEK RESULTING
IN WET AND WARMER WEATHER FOR ALL LOCATIONS.
&&
.DISCUSSION...
TODAY AND TONIGHT...UPPER LEVEL PATTERN WILL DEVIATE LITTLE FROM
YESTERDAY WITH THE HIGH AMPLITUDE RIDGE EXTENDING INTO ALASKA AND
SWIFT NORTHWEST FLOW STRETCHING FROM THE YUKON INTO THE PACNW.
THIS WILL RESULT IN THE CONTINUATION OF UNSEASONABLY COLD WEATHER
FOR YET ANOTHER DAY WITH HIGH TEMPS REMAINING ANYWHERE FROM 15-20
DEGREES BELOW NORMAL. THE MAIN DEVIATION BETWEEN TODAY AND
YESTERDAY IS THE UPPER LEVEL FLOW WILL TURN MORE
NORTHWESTERLY...ALLOWING THE JET TO SHIFT OUT OF OUR NORTHEAST
ZONES AND INTO WESTERN MONTANA. THIS WILL TAKE THE CURRENT BATCH
OF MID AND HIGH LEVEL MOISTURE...CURRENTLY STREWN OVER EXTREME NE
WASHINGTON THE IDAHO PANHANDLE...SLOWLY EASTWARD THROUGH THE DAY.
THE DEPARTING MOISTURE WILL GRADUALLY END THE THREAT OF FLURRIES
OVER THE IDAHO PANHANDLE.
ELSEWHERE...SKIES WILL GENERALLY BE FILLED WITH SUNSHINE...ALLOWING
THE ARCTIC AIRMASS TO MODIFY FURTHER...WITH A COUPLE OF DEGREES OF
WARMING EXPECTED FOR MOST LOCATIONS. DESPITE THE OVERALL WARMING
OF THE LOWER ATMOSPHERE...THE LOW LEVEL MIXING POTENTIAL WILL
REMAIN QUITE LIMITED DUE TO WEAK PRESSURE GRADIENTS AND THE
RESULTANT LIGHT WINDS. THUS THE SURFACE WARMING WILL BE OUTPACED
BY THE 2-4C OF WARMING WE WILL SEE AT 850 MBS COMPARED TO
YESTERDAYS VALUES. NIGHTTIME LOW TEMPERATURES VALUES WILL SHOW A
WIDE VARIATION ACROSS THE CWA AND MUCH WILL DEPEND ON POTENTIAL
CLOUDINESS. BOTH THE NAM AND GFS SUGGEST WE WILL SEE A GOOD INFLUX
OF HIGH AND MID LEVEL MOISTURE TONIGHT...ASSOCIATED WITH THE BATCH
OF CLOUDS CURRENTLY OVER NORTHERN BC. HOW MUCH THIS BLANKETS THE
LONGWAVE RADIATION TONIGHT WILL BE THE BIG QUESTION...BUT THE
MODELS ARE CONSISTENT IN FORECASTING THE DEEPEST MOISTURE OVER THE
NORTHEASTERN 2/3RDS OF THE CWA. THUS THE COOLEST TEMPS COULD ONCE
AGAIN OCCUR OVER THE LOWER COLUMBIA BASIN WHERE LOWER SINGLE
DIGITS WILL BE POSSIBLE. FX
FRIDAY THROUGH SUNDAY NIGHT...MODELS IN PRETTY GOOD AGREEMENT FOR
THE FIRST 36 HRS OF THE EXTENDED PERIOD...THEN CONFIDENCE GOES
DOWNHILL FROM THERE. THE MONSTER LOW IN NORTHERN CANADA WILL
CONTINUE TO SPIN AND MODELS AGREE ON A PIECE OF ENERGY FROM THAT
MOVING OUT OF NORTHERN BC DOWN TOWARDS THE US BORDER BY SUNDAY
NIGHT. IN THE MEANTIME ENERGY FROM THE EASTERN PACIFIC WILL MOVE
INTO OREGON AND DRIFT NORTH TOWARDS SOUTHEASTERN WA AND CENTRAL ID.
FORECAST WILL REMAIN DRY FRIDAY AND FRIDAY EVENING. HOWEVER AS THE
WEATHER FEATURE MOVES IN FROM THE SOUTH...CHANCES OF SNOW WILL
INCREASE SOUTH OF A LINE FROM THE BLUES TO PULLMAN TO MULLAN PASS
SATURDAY. MEANWHILE THAT ENERGY FROM CANADA AND A SURFACE HIGH WILL
MOVE SOUTH OUT OF CANADA. THIS WILL PROVIDE CONTINUED COLD
TEMPERATURES AND A CHANCE OF LIGHT SNOW ACROSS NORTHERN WA AND ID.
SPOKANE WILL BE IN THE SADDLE POINT OF THE TWO SYSTEMS WITH THE BEST
CHANCE OF PRECIP TO THE NORTH AND SOUTH OF TOWN. TEMPERATURES WILL
REMAIN BELOW AVERAGE FOR THIS TIME OF THE YEAR.
MONDAY THROUGH WEDNESDAY...A SHORTWAVE RIDGE MOVES IN MONDAY AHEAD
OF THE NEXT PACIFIC SYSTEM ALONG WITH A DECENT UPPER LEVEL JET.
MODELS SHOWING A GOOD AMOUNT OF MOISTURE MOVING INTO THE
AREA...COUPLED WITH THE JET SUPPORT...HAVE CONTINUED WITH THE IDEA
OF AT OR ABOVE AVERAGE CHANCE OF PRECIP THROUGH THE REMAINDER OF
THE EXTENDED PERIOD. MODELS ARE FINALLY INDICATING THAT POSSIBLY
BY TUESDAY NIGHT WARMER 850 MB TEMPERATURES COULD BE MOVING INTO
THE PAC NW. THERE ARE STILL SOME UNCERTAINTIES WITH REGARDS TO THE
LOW PRESSURE SYSTEM MOVING INTO CANADA AND DRAGGING THAT WARMER
AIR INTO THE AREA. HOW QUICKLY THE COLD AIR ERODES WILL DETERMINE
THE DIFFERENCE BETWEEN A RAIN OR SNOW EVENT. AT THIS POINT WENT
WITH A SNOW EVENT WITH THE BEST CHANCE OF RAIN BEING ACROSS THE
DEEP BASIN. BY TUE/WED TEMPERATURES WILL RETURN TO MORE AVERAGE
READINGS FOR THIS TIME OF THE YEAR. /NISBET
&&
.AVIATION...
VFR CONDITIONS SHOULD PREVAIL THROUGH 11/12Z AS DRY NORTHWEST FLOW
ALOFT CONTINUES OVER THE AREA. THE ONLY POTENTIAL AVIATION CONCERN
WILL BE A MID LEVEL CLOUD DECK EXTENDING FROM THE NE CORNER OF WA
INTO THE CENTRAL ID PANHANDLE. CIGS FROM THIS DECK WILL RANGE FROM
060-080 PRODUCING SOME MTN OBSCURRATIONS THROUGH THE EARLY
AFTERNOON. THERE COULD ALSO BE A FEW FLURRIES FROM THIS CLOUD DECK.
FX
&&
.PRELIMINARY POINT TEMPS/POPS...
SPOKANE 18 9 23 13 24 17 / 0 0 0 10 30 50
COEUR D'ALENE 22 11 26 14 27 20 / 0 0 0 10 40 50
PULLMAN 19 9 26 16 29 24 / 0 0 0 10 60 60
LEWISTON 20 11 30 18 32 26 / 0 0 0 10 60 80
COLVILLE 20 9 23 14 27 20 / 0 0 0 20 20 20
SANDPOINT 16 7 21 10 23 18 / 10 0 10 20 30 40
KELLOGG 15 8 23 14 25 24 / 10 10 0 20 60 60
MOSES LAKE 22 2 24 11 26 17 / 0 0 0 10 20 20
WENATCHEE 22 9 24 13 26 17 / 0 0 0 10 20 20
OMAK 26 4 24 9 27 15 / 0 0 0 20 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
WA...NONE.
&&
$$
