Wind Chill Advisory 2, NWS Elko, NV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ELKO NV
210 PM PST FRI DEC 26 2008

.SYNOPSIS...HIGH PRESSURE BUILDING OVER THE REGION WILL ALLOW
TEMPERATURES TO PLUMMET UNDER CLEARING SKIES AND A FRESH SNOW PACK
EARLY TONIGHT BEFORE CLOUDS AGAIN INCREASE LATER TONIGHT. A SERIES
OF DISTURBANCES MOVING THROUGH THE PACIFIC NORTHWEST WILL BRING
SOME LIGHT MIXED RAIN AND SNOW MAINLY TO NORTHERN AREAS THROUGH
THE WEEKEND.

&&

.SHORT TERM...TONIGHT THROUGH MONDAY. LATEST SATELLITE IMAGERY IS
INDICATING THE STRATOCU DECK OF CLOUDS SLOWLY THINNING AS
SUBSIDENCE STRENGTHENS BENEATH A BUILDING RIDGE AT THE SURFACE/ALOFT
OVER THE CWA THIS AFTERNOON. WITH THE LOSS OF HEATING...EXPECT MANY
LOCATIONS TO BE CLEAR/PARTLY CLOUDY FOR SEVERAL HOURS ALLOWING
TEMPERATURES TO REACH SUBZERO VALUES IN MANY LOCATIONS EARLY
TONIGHT. HOWEVER...CLOUDS WILL BE ON THE INCREASE AS A WEAK SHORT
WAVE MOVES INTO THE PACIFIC NORTHWEST WHICH WILL HELP CAP
TEMPERATURES LATER TONIGHT.

LATEST 12Z MODELS ARE IN GOOD AGREEMENT THAT WEAK FORCING WITHIN
THE MID LEVEL WAA PATTERN ASSOCIATED WITH A WARM FRONT JUST CLIPPING
THE STATE WILL PRODUCE A PERIOD OF LIGHT SNOW OR MIXED PRECIPITATION
MAINLY FOR HUMBOLDT AND NORTHERN ELKO COUNTIES DURING SATURDAY. AN
INCH OR TWO OF SNOW ACCUMULATION IS POSSIBLE OVER EXTREME NORTHERN
HUMBOLDT AND NORTHERN ELKO COUNTIES WITH AN INCH OR LESS ELSEWHERE
OVER THE REMAINDER OF NORTHERN NEVADA SATURDAY.

RESIDUAL MOISTURE HOLDS ON ACROSS THE STATE RESULTING IN MOSTLY
CLOUDY CONDITIONS SATURDAY NIGHT. MODEL SOUNDINGS ARE INDICATING
THE DEPLETION OF HIGH CLOUDS OVER HUMBOLDT/ELKO COUNTIES WHICH MAY
POSSIBLY LEAD TO SOME PATCHY FREEZING DRIZZLE WITH ISOTHERMAL
PROFILE IN THE SUBCLOUD LAYER WITH LOW LEVEL MOISTURE IN PLACE.
WITH CLOUDS IN PLACE EXPECT TEMPERATURES TO BE AT LEAST 10 TO 15
DEGREES WARMER SATURDAY NIGHT VS. FRIDAY NIGHT.

A SERIES OF SHORT WAVES MAINLY NORTH OF THE STATE TRAVERSING
THROUGH THE ZONAL FLOW IS EXPECTED TO KEEP UNSETTLED CONDITIONS
ACROSS NORTHERN NEVADA ALONG WITH MAINLY DRY CONDITIONS FURTHER
SOUTH SUNDAY THROUGH MONDAY.

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...THE MODELS BRING A
RELATIVELY WEAK COLD FRONT THROUGH THE AREA ON MONDAY NIGHT. DID
BELIEVE THAT THIS WARRANTED SOME LOW CHANCES FOR PRECIPITATION IN
THE NORTHERN COUNTIES GIVEN THE GOOD MODEL AGREEMENT. THE BIG
DIFFERENCE IN THE MODELS COMES ON TUESDAY AND WEDNESDAY REGARDING
THE UPPER PATTERN. THE LATEST GFS BRINGS A SIGNIFICANT SYSTEM
THROUGH THE REGION ON WEDNESDAY/NEW YEARS EVE...WHILE THE ECMWF IS
DRY AND TRYING TO BUILD A RIDGE OVER THE REGION. THE
CANADIAN...06Z GFS...AND THE GFS ENSEMBLES SHOW THE POTENTIAL FOR
A SYSTEM AS WELL BUT NOT NEARLY AS SIGNIFICANT AS THE 12Z OPERATIONAL
GFS. DECIDED TO GO WITH SOME PRECIPITATION POTENTIAL IN THE
NORTH...BUT KEPT CHANCES LOW FOR NOW.

GIVEN THE UNCERTAINTY OF THE UPPER PATTERN TOWARDS THE END OF THE
WEEK...DECREASED CHANCES FOR PRECIPITATION SLIGHTLY. ALSO KEPT
TEMPERATURES NEAR THE MIDDLE OF THE ROAD FOR NOW AS WELL.

&&

.AVIATION...LINGERING LOW LEVEL CLOUDS WILL DISSIPATE QUICKLY THIS
EVENING UNDER GOOD SUBSIDENCE. MID LEVEL CLOUDS WILL INCREASE LATER
TONIGHT AS WARM AIR ADVECTION ALOFT BEGINS. CONSIDERED FOG POTENTIAL
TONIGHT AS WELL GIVEN THE RECENT PRECIP AND WARM AIR ADVECTION
ALOFT. BELIEVE INCREASING CLOUD COVER WILL LIMIT RADIATIONAL COOLING
HOWEVER. WITH THE WARM AIR ADVECTION...SNOW WILL BE POSSIBLE AT KWMC
BY SUNRISE AND AT EKO BY LATE MORNING. WILL LIKELY DROP KEKO AND
KWMC TO MVFR CATEGORY FOR THE AFOREMENTIONED TIME FRAMES WITH THE
NEXT TAF ISSUANCE.

&&

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

&&

89/88/83