FXUS65 KLKN 261029
AFDLKN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ELKO NV
229 AM PST THU NOV 26 2009
.SYNOPSIS...THANKSGIVING DAY WILL BE PLEASANT AS DRY CONDITIONS CONTINUE
AND TEMPERATURES RISE INTO THE 50S. AS A LOW PRESSURE SYSTEM APPROACHES
FRIDAY...CLOUDS WILL SPREAD ACROSS THE GREAT BASIN. RAIN AND SNOW SHOWERS
WILL BEGIN FRIDAY MORNING OVER HUMBOLDT COUNTY AND SLOWLY MOVE EAST
THROUGH SATURDAY. LITTLE SNOW ACCUMULATION IS EXPECTED IN THE VALLEYS...HOWEVER
A COUPLE INCHES CAN BE EXPECTED FOR THE MOUNTAINS OF NORTHERN NEVADA.
A DRIER REGIME WILL RETURN BY SUNDAY.
&&
.SHORT TERM...TODAY THROUGH SATURDAY. IR IMAGERY REVEALS CLEAR
SKIES ALL ACROSS THE CWA THIS MORNING AS A LARGE RIDGE ENVELOPS
THE GREAT BASIN...PROMISING A PLEASANT THANKSGIVING DAY. CURRENT
RIDGE PRODUCING THE EVENT-FREE HOLIDAY IS SLOWLY PROGRESSING EAST.
ATTM CLOUD FIELD ON THE BACK SIDE OF THE RIDGE IS PUSHING THROUGH
NORTHERN CALIFORNIA.
MODELS ARE HAVING DIFFICULTY SYNCHING WITH ONSET OF PRECIPITATION
FROM ADVANCING LOW. APPEARS THAT THE GFS MODEL IS PROJECTING THE
CURRENT CLOUDINESS TOO FAR EAST COMPARED TO THE MORE ACCURATE
INITIALIZATION OF THE NAM AND ECMWF. HOWEVER AT SATURDAY 00Z ALL
THREE MODELS SHOW THE ADVANCING TROUGH CENTERED OVER WEST CENTRAL
CALIFORNIA...A TENDENCY TO PULL TOWARD THE PREVIOUS ECMWF
SOLUTION. ALL THREE MODELS TRACK THE SYSTEM SIMILARLY TO REPOSITION
CENTRAL LOW PRESSURE SOUTH OF THE TIP OF SOUTHERN NEVADA BY SUN
00Z. GFS CENTERS THE LOW ABOUT 100 MILES FURTHER NORTH THAN THE
NAM AND THE ECMWF AT THAT POINT IN TIME. THIS PATTERN WILL LEAD TO
A DRIER SCENARIO FOR THE REST OF THE HOLIDAY WEEKEND. AT PRESENT
THE HIGHER QPF...RELATIVELY LIMITED...WILL BE IN THE NORTH AS
PREVIOUS MODEL RUNS HAVE INDICATED. HOWEVER THE FOCUS AS SEEN NOW
SHOULD BE OVER HUMBOLDT COUNTY AND NORTHERN LANDER COUNTY LATE
FRIDAY THROUGH FRIDAY NIGHT BEFORE THE PRECIPITATION CORE GETS
YANKED SOUTH BY THE DIGGING ACTION OF THE LOW. THINK A COUPLE
INCHES OF SNOW FOR THE MOUNTAINS OF HUMBOLDT AND NORTHERN LANDER
COUNTIES IS NOT UNREASONABLE. ADJUSTED POPS/TEMPS A LITTLE AND RE-
FOCUSED THE PRECIPITATION CONCENTRATION...OTHERWISE FORECAST IS IN
GOOD SHAPE.
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY. MODELS SHOWS A RIDGE
OF HIGH PRESSURE BUILDING INTO THE GREAT BASIN BY SATURDAY NIGHT IN
THE WAKE OF A SPLIT TROUGH THAT AFFECTS THE REGION ON SATURDAY. DUE
TO GOOD AGREEMENT IN THE MODELS HAVE REMOVED ALL PRECIP SATURDAY
NIGHT WITH UPPER LOW OVER SOCAL BY THAT TIME. WITH THE RIDGE
BUILDING DOWN FROM THE NORTH ON SUNDAY...COOL NORTHERLY FLOW WILL
KEEP TEMPS NEAR OR SLIGHTLY BELOW NORMAL. HIGHS WILL GENERALLY BE IN
THE 30S AND 40S. THE RIDGE WILL REMAIN IN PLACE ON MONDAY FOR DRY
CONDITIONS AND NEAR NORMAL TEMPS. A RATHER STRONG UPPER TROUGH WILL
MOVE INTO THE NORTHERN ROCKIES ON TUESDAY THEN DIG SOUTHWARD INTO
THE GREAT BASIN ON WEDNESDAY. BEST CHANCE OF PRECIP WILL BE NORTH OF
OUR CWA...BUT STILL SHOULD SEE A FEW SNOW SHOWERS OVER NE NV. THE
BIGGEST IMPACT WILL BE THE POSSIBILITY OF SOME COLD AIR REACHING
NORTHERN NV BY WEDNESDAY...WITH H7 TEMPS AROUND -15C TO -17C. THIS
WOULD TRANSLATE INTO DAYTIME HIGHS IN THE MID 20S TO MID 30S. HAVE
NOT TRENDED TEMPS QUITE THAT COLD YET...BUT MAY HAVE TO IN THE
COMING DAYS IF MODELS CONTINUE TO AGREE.
&&
.AVIATION...A RIDGE OF HIGH PRESSURE WILL CONTINUE TO INFLUENCE
NORTHERN AND CENTRAL NEVADA OVER THE NEXT 24 HR PERIOD. VFR
CONDITIONS AND LIGHT WINDS ARE ANTICIPATED AT ALL TAF SITES.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
92/99/99