Strong Wind in Nevada, March 10, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
345 AM PST THU MAR 10 2011

.SHORT TERM...
LOW PRESSURE TROUGH MOVING INTO THE PACIFIC NORTHWEST WILL BRING
GUSTY WINDS TO THE SIERRA AND WESTERN NEVADA TODAY...AND LIGHT RAIN
AND SNOW MAINLY TO THE SIERRA. WINDS HAVE ALREADY BEGUN TO INCREASE
IN THE SIERRA AHEAD OF THIS TROUGH WITH VARIOUS OBSERVATIONS IN THE
TAHOE BASIN REPORTING GUSTS TO 20-25 MPH AS OF 2 AM. BUOY DATA ON
LAKE TAHOE IS ALSO SHOWING SUSTAINED WINDS 15-20 MPH...SO BUMPED UP
THE START TIME FOR THE LAKE WIND ADVISORY TO 4 AM. THE FLOW ALOFT
WILL CONTINUE TO INCREASE THROUGH THE MORNING...WITH GUSTY SOUTH TO
SOUTHWEST WINDS SURFACING IN THE WESTERN NEVADA VALLEYS AROUND MID
DAY INTO THE EVENING HOURS. STRONGEST WINDS WILL BE ALONG THE 395
CORRIDOR FROM STEAD-RENO-CC SOUTH TO LEE VINING-MAMMOTH. NAM12 SEEMS
TO BE OVERDOING THE LOW LEVEL WINDS IN THE LEE OF THE SIERRA AS THE
SPEED OF THE TROUGH AND OVERALL FLOW IS LESS THAN IDEAL FOR A STRONG
MOUNTAIN WAVE. STILL...SHOULD SEE GUSTS 45-50 MPH ACROSS A LARGE
AREA...WITH LOCALLY HIGHER GUSTS BRIEFLY POSSIBLE IN WIND PRONE
AREAS SUCH AS GALENA.

CONCERNING THE PRECIP POTENTIAL...RAIN/SNOW SHOULD GRADUALLY MOVE
INTO THE SIERRA NORTH OF TAHOE BY LATE AFTERNOON WITH SNOW LEVELS
NEAR OR JUST ABOVE 7000 FEET. MODEL CROSS SECTIONS SHOW ONLY A VERY
BRIEF PERIOD OF MARGINALLY DEEP MOISTURE (TO 500 MB) THIS AFTERNOON
AS THE FRONT MOVES THROUGH...WITH THE BULK OF THE ENERGY REMAINING
NORTH OF THE AREA. MODELS HAVE TRENDED LOWER WITH THE QPF...WITH THE
GFS/ECMWF NOW ONLY SHOWING 0.10-0.20 INCHES ALONG THE TAHOE CREST UP
TO ABOUT 0.40 OVER WESTERN LASSEN. EXPECT ONLY ABOUT HALF OF THIS OR
LESS TO SPILL OVER INTO THE TAHOE BASIN...WITH VERY LITTLE IF ANY
PRECIP MAKING IT OVER THE CARSON RANGE INTO WESTERN NEVADA. IT WILL
BE MOSTLY RAIN AT LAKE LEVEL WITH ACCUMULATING SNOW OCCURRING IN
AREAS ABOVE 7000 FEET...AND GENERALLY CONFINED TO THE CREST. TO THE
EAST OF THE SIERRA...DECREASED THE POPS FOR RENO-CC-MINDEN AS IT
WILL GENERALLY BE A NICE DAY...ALBEIT A BREEZY ONE...WITH PERHAPS
ONLY A BRIEF SPIT OF RAIN LATE IN THE DAY FOR AREAS WEST OF HIGHWAY
395. WILL BE LUCKY TO SEE A TRACE TO ONE HUNDREDTH OF AN INCH AT THE
RENO AIRPORT. REMOVED MENTION OF RAIN FROM AREAS SOUTH OF I-80 AND
EAST OF 395 INCLUDING SPARKS...SPANISH SPRINGS...FERNLEY.

THE LOW WILL QUICKLY MOVE EAST OF THE FORECAST AREA OVERNIGHT
BRINGING AN END TO THE THREAT FOR PRECIP AND GUSTY WINDS. THERE IS
NOT A LOT OF COLD AIR BEHIND THIS SYSTEM...AND WITH A SHORTWAVE
RIDGE IMMEDIATELY BUILDING FRIDAY...TEMPS WILL REMAIN MILD. HIGHS
FRIDAY AND SATURDAY WILL STILL BE AROUND 60 DEGREES IN WESTERN NV
VALLEYS AND IN THE 50S IN SIERRA VALLEYS.

ANOTHER SHORTWAVE WAVE TROUGH MOVING INTO THE PACIFIC NORTHWEST WILL
BRUSH US BY TO THE NORTH ON SATURDAY BRING A SLIGHT CHANCE OF LIGHT
SHOWERS OVER LASSEN-PLUMAS COUNTIES...AND FAR NORTHERN WASHOE AND
THE SURPRISE VALLEY. SCV

.LONG TERM...SUNDAY THROUGH THURSDAY...
THE LONGWAVE TROUGH WILL REMAIN ANCHORED OFF THE WEST COAST AT
ROUGHLY 135 WEST THROUGH THE EXTENDED PERIOD. THE PARADE OF FAST
MOVING SHORTWAVES EJECTED FROM THE PARENT LONGWAVE TROUGH WILL
CONTINUE...WITH THE MAIN FORECAST CHALLENGES BEING THE TIMING AND
AMOUNT OF MOISTURE EACH SYSTEM CAN TAP FROM THE SUBTROPICS.

SUNDAY LOOKS TO BE THE NICER OF THE TWO WEEKEND DAYS AS A
SHORTWAVE RIDGE MOVES ACROSS THE FORECAST AREA. HIGH CLOUDS WILL
BUILD SUNDAY AFTERNOON AHEAD OF THE NEXT WAVE. THE BEST CHANCE FOR
PRECIP WITH THIS WAVE WILL BE LATE SUNDAY NIGHT IN THE SIERRA FROM
TAHOE NORTH AND VALLEY AREAS NORTH OF GERLACH AS THE BEST DYNAMICS
AND JET SUPPORT REMAIN WELL NORTH OF THE CWA. THE GFS AND ECMWF
SUGGEST SHOWERS MAY LINGER IN THE HIGHER ELEVATIONS NORTH OF TAHOE
ON MONDAY AS A WEAKER TRAILING SHORTWAVE BRUSHES BY TO THE NORTH.

AFTER A BREAK ON MONDAY NIGHT...A STRONGER SYSTEM WITH A 130+ KT
JET APPROACHES THE NORCAL COAST ON TUESDAY. THE 00Z GFS AND ECMWF
DIFFER QUITE A BIT ON THE TIMING AND AMOUNT OF MOISTURE TAPPED BY
THIS SYSTEM. THE GFS IS SLOWER AND DRIER...SHOWING MORE OF A BRUSH
BY SYSTEM FOR WEDNESDAY. THE ECMWF IS FASTER AND MORE
AMPLIFIED...ALLOWING THE 130+ KT JET TO SAG SOUTH ACROSS CENTRAL
CA. THIS SOLUTION OPENS THE DOOR FOR A MORE PROLONGED PERIOD OF
PRECIP IN THE SIERRA WITH SPILLOVER ACROSS WESTERN NEVADA VALLEYS
FROM LATE TUESDAY THROUGH EARLY THURSDAY. WITH THE MODELS
STRUGGLING TO AGREE...DECIDED TO STICK WITH CURRENT POP FORECAST
KEEPING THE BEST CHANCE OF PRECIP ON WEDNESDAY.

TEMPS ARE EXPECTED TO RUN ABOUT 5 DEGREES ABOVE SEASONAL NORMS
THROUGH THE EXTENDED...KEEPING SNOW LEVELS WELL ABOVE THE VALLEY
FLOORS OF WESTERN NEVADA. MYRICK

&&

.AVIATION...
MAIN OPERATIONAL CONCERN TODAY WILL BE GUSTY WINDS AT ALL
TERMINALS AHEAD OF THE APPROACHING SHORTWAVE TROUGH. NOT EXPECTING
MUCH IN THE WAY OF PRECIP AT KRNO WITH THIS SYSTEM. KTVL AND KTRK
MAY EXPERIENCE A BRIEF PERIOD OF MVFR CIGS/VIS BETWEEN 21 AND 03Z
AS SHOWERS PASS NEAR THESE TERMINALS. TURBULENCE CAN BE EXPECTED
DOWNSTREAM OF THE SIERRA CREST TODAY AS CREST LEVEL WINDS ARE
FORECAST TO GUST TO 60 KTS...WITH ROTOR FORMATION POSSIBLE NEAR
KRNO. MYRICK

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY FROM 11 AM THIS MORNING TO 9 PM PST THIS
     EVENING NVZ004.

     WIND ADVISORY FROM 11 AM THIS MORNING TO 9 PM PST THIS EVENING
     NVZ003.

     LAKE WIND ADVISORY UNTIL 9 PM PST THIS EVENING NVZ002.

CA...WIND ADVISORY FROM 11 AM THIS MORNING TO 9 PM PST THIS EVENING
     CAZ073.

     LAKE WIND ADVISORY UNTIL 9 PM PST THIS EVENING CAZ072.

&&

HTTP://WEATHER.GOV/RENO