FXUS65 KLKN 071926 AAA
AFDLKN

AREA FORECAST DISCUSSION...RETRANSMISSION
NATIONAL WEATHER SERVICE ELKO NV
426 AM PST MON DEC 7 2009

.SYNOPSIS...A WINTER STORM WILL BRING LIGHT TO MODERATE ACCUMULATIONS
TO NORTHERN AND CENTRAL NEVADA TODAY AND TONIGHT. COLD TEMPERATURES
WILL CONTINUE THROUGH FRIDAY...WITH A WARMING TREND SATURDAY AND
SUNDAY. ANOTHER WINTER STORM WILL BE POSSIBLE NEXT WEEKEND. 
&&

.SHORT TERM...TODAY THROUGH WEDNESDAY. AT 500MB SHORT-TERM MODELS
AGREE ON NORTHERN CALIFORNIA LOW MOVING EAST OVER FORECAST AREA
TONIGHT. UPPER SUPPORT WILL BE PROVIDED BY COMPLEX JET STRUCTURE...
WITH GREATEST SUPPORT SOUTH ACROSS VEF FCST AREA. SNOWFALL WILL INCREASE
IN INTENSITY AND COVERAGE THIS MORNING AND AFTERNOON...AND THEN
BEGIN DIMINISHING FROM WEST TO EAST LATE EVENING TO AROUND
MIDNIGHT. THE EXCEPTIONS WILL BE HUMBOLDT COUNTY WHERE SNOW WILL
PICK-UP AND END EARLIER AND BE PRIMARILY ACROSS THE SOUTHEAST IN
THE WMC AREA...AND WHITE PINE COUNTY WHERE SNOW ACTIVITY WILL
CONTINUE AFTER MIDNIGHT ACROSS SOUTHEAST PORTIONS OF THE COUNTY.

BECAUSE OF THE COMPLEXITY OF THE EVENT...WHERE THE ONLY SURE THING
IS COLD TEMPERATURES...TIMING AND AMOUNTS WILL BE HARD TO PIN
DOWN. IN GENERAL SNOWFALL AMOUNTS OF 1 TO 3 INCHES IN VALLEYS AND
2 TO 5 INCHES IN THE MOUNTAINS SEEMS THE BEST BET. IT IS POSSIBLE
THAT MOST OF THE SNOWFALL MAY OCCUR IN ONE SHORT 2 TO 3 HOUR
BURST...AS THE GFS INDICATES FOR ELKO THIS AFTERNOON. IF THIS
HAPPENS....WE MAY REACH WINTER WEATHER ADVISORY CRITERIA. THE DAY
SHIFT WILL NEED TO RE- EVALUATE. IN THE MEANTIME WILL BE BEEFING
UP THE GRIDS TO RAISE QPF AND SNOWFALL AMOUNTS TO JUST BELOW
ADVISORY CRITERIA.

THE TROF AXIS SHIFTS EAST INTO UTAH TUESDAY MORNING. ISOLATED
FLURRIES WILL LINGER TUESDAY. A SHARP SHORT WAVE WILL ZIP ACROSS
THE FCST AREA TUESDAY NIGHT...TRIGGERING ADDITIONAL FLURRIES.
WEDNESDAY WILL SEE A DRY NW FLOW AT 500MB ACROSS THE AREA WITH
CONTINUED COLD TEMPERATURES. REA

.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY. UNSETTLED WEATHER 
PATTERN TO PERSIST THROUGH THE LONG TERM AS A LONG WAVE TROUGH 
REMAINS POSITIONED OVER THE WESTERN UNITED STATES. HOWEVER...LATEST 
OPERATIONAL GUIDANCE FROM THE GFS AND ECMWF CONTINUES TO INSIST ON A 
RELATIVELY BENIGN LATE WEEK FOLLOWED BY AN ACTIVE WEEKEND. STORM 
SYSTEM WHICH HAD PREVIOUSLY BEEN EXPECTED TO MOVE INLAND ACROSS THE 
REGION THURSDAY AND FRIDAY CONTINUES TO BE SHEERED OUT AND 
SUPPRESSED TO OUR SOUTH BY BOTH THE GFS AND ECMWF. THIS HAS BEEN THE 
TREND FOR THE LAST SEVERAL OPERATIONAL RUNS...AND I FIND IT HARD TO 
IGNORE. THUS...CUT POPS AND SKY COVER THURSDAY AND 
FRIDAY...ESPECIALLY ACROSS THE NORTHERN HALF OF THE CWA. 
HOWEVER...IN THIS SAME VEIN...BOTH MODELS CONTINUE TO INSIST ON A 
SYSTEM PLOWING INTO THE REGION OVER THE WEEKEND WITH A DECENT AMOUNT 
(QUARTER TO PERHAPS AS MUCH AS A HALF INCH) OF QPF. HOWEVER...THIS 
SYSTEM...AND IMPULSES FOLLOWING IN ITS WAKE...WILL BE BRINGING IN 
SOME MILDER MARITIME AIR WITH THEM...SO WHILE PRECIPITATION IS 
BECOMING INCREASINGLY LIKELY...TEMPERATURES ARE ALSO LIKELY TO 
MODERATE AWAY FROM THE RECENT SEVERE COLD AND BACK TOWARDS NORMAL. 
THIS MARITIME AIR WILL ALSO RAISE SNOW LEVELS...AND THE LOWEST 
VALLEYS MAY HAVE RAIN/MIX ISSUES OVER THE WEEKEND. RCM

&&

.AVIATION...PACIFIC STORM SYSTEM WILL BRING SNOW SHOWERS TO THE 
REGION TODAY...WITH SOME STEADY SNOW EXPECTED THIS AFTERNOON AT 
KWMC...AND THIS EVENING AT KEKO...KELY...AND KTPH. SNOW MAY LINGER 
THROUGH THE NIGHT AT KEKO AND KELY. PREDOMINANTLY MVFR CONDITIONS 
ARE EXPECTED...WITH BRIEF PERIODS OF IFR CONDITIONS (CIGS AND VIS) 
ALSO LIKELY DURING STEADIER PERIODS OF SNOWFALL. WINDS WILL NOT BE A 
BIG CONCERN UNTIL LATER TONIGHT WHEN GUSTY NORTHWEST WINDS WILL 
DEVELOP AT KTPH. RCM
&&

.LKN WATCHES/WARNINGS/ADVISORIES...NONE. 
&&

$$

90/93/93