Area Forecast Discussion
Issued by NWS Reno, NV

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
000
FXUS65 KREV 262234
AFDREV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
235 PM PST WED NOV 26 2014

.SYNOPSIS...
HIGH PRESSURE WILL BRING WELL ABOVE NORMAL TEMPERATURES AND DRY
CONDITIONS THROUGH FRIDAY. LOW PRESSURE WILL MOVE INTO THE WEST
COAST FRIDAY NIGHT WITH PERIODS OF GUSTY WINDS, RAIN AND SIERRA SNOW
THIS WEEKEND AND INTO EARLY NEXT WEEK.

&&

.SHORT TERM...

HIGH PRESSURE RIDGE REMAINS OVER THE REGION FOR THANKSGIVING AND
INTO FRIDAY. SOME HIGH CLOUDS MOVING IN OVERNIGHT WILL KEEP
TEMPERATURES A BIT WARMER THAN WHAT WE SAW LAST NIGHT, ALONG WITH
WEAKER VALLEY INVERSIONS. WELL ABOVE NORMAL TEMPERATURES CONTINUE
INTO THANKSGIVING WITH HIGHS PEAKING OUT IN THE MID TO UPPER 60S. AT
THE RENO-TAHOE AIRPORT WE SHOULD BE A COUPLE DEGREES LOW OF THE
RECORD OF 70 DEGREES SET BACK IN 1946. IF THE CLOUDS CLEAR OUT
EARLIER IN THE DAY, WE COULD APPROACH OR EVEN BREAK THE RECORD, BUT
FOR NOW THAT LOOKS UNLIKELY.

AS WE GO INTO FRIDAY NIGHT AND SATURDAY, INCREASED MOISTURE WILL
START TO MOVE INTO NORTHERN CA COMBINING WITH LOW PRESSURE DROPPING
INTO THE PACIFIC NORTHWEST. THIS WILL BRING PERIODS OF RAIN AND HIGH
ELEVATION SNOW THROUGH SATURDAY NIGHT. SNOW LEVELS WILL BEGIN AROUND
7000 FEET FRIDAY NIGHT, THEN DROP TO AROUND 6500 FEET SATURDAY
NIGHT. FORECAST CONFIDENCE IS MEDIUM TO HIGH ON THE WEEKEND SYSTEM,
SO WE`VE CONTINUED TO RAISE THE CHANCE OF PRECIPITATION FOR THE
TAHOE BASIN NORTHWARD INTO THE "LIKELY" CATEGORY. THE MOST
UNCERTAINTY IN THE SHORT TERM FORECAST LIES IN THE AMOUNT OF
PRECIPITATION. FOR NOW, WE EXPECT TO SEE TOTAL PRECIPITATION AMOUNTS
THROUGH SATURDAY NIGHT OF 0.20-0.50" IN THE SIERRA WITH LIGHT RAIN
LESS THAN 0.10" IN WESTERN NEVADA. GUSTY WINDS OF UP TO 40 MPH ARE
ALSO POSSIBLE ON FRIDAY AND SATURDAY WITH THIS SYSTEM, ESPECIALLY
ALONG THE HIGHWAY 395 CORRIDOR.

THE MAIN TRAVEL IMPACTS WILL BE FOR THE SIERRA PASSES ABOVE 7000
FEET WITH POTENTIAL OF SEVERAL INCHES OF SNOW. ANYONE TRAVELING OVER
THE SIERRA SATURDAY OR SATURDAY NIGHT SHOULD BE PREPARED FOR SLICK
WINTER ROAD CONDITIONS. HOON

.LONG TERM...SUNDAY THROUGH WEDNESDAY...

WHILE ACTIVE WEATHER PATTERN IS STILL PROBABLE FROM SUNDAY THROUGH
THE MIDDLE OF NEXT WEEK, THE TIMING OF THE HEAVIER PRECIPITATION AND
POTENTIAL RAIN OR SNOW AMOUNTS HAVE BECOME FAR MORE UNCERTAIN. MAJOR
CHANGES IN SOME OF THE MODEL GUIDANCE, AND HIGH LEVEL OF SPREAD
AMONG ENSEMBLE DATA HAS FURTHER LOWERED CONFIDENCE AS TO WHICH DAYS
ARE MORE LIKELY TO BE WET NEXT WEEK.

THERE IS A LITTLE BETTER AGREEMENT WITH SUNDAY TRENDING WETTER, AS
SHORTWAVE BREAKING OFF FROM THE MAIN LOW MOVES ACROSS NORTHERN AND
CENTRAL CA, WITH PACIFIC MOISTURE ALREADY IN PLACE. THE BEST CHANCE
FOR RAIN AND HIGH ELEVATION SNOW IS PROJECTED FROM TAHOE NORTHWARD
TO NORTHEAST CA, WITH LIGHTER RAIN POSSIBLE IN WESTERN NV NORTH OF
INTERSTATE 80. SNOW LEVELS ARE GENERALLY EXPECTED TO RANGE FROM 6500
TO 7500 FEET, HOWEVER THE GFS AND ECMWF BOTH SHOW A POCKET OF COOLER
700 MB TEMPS AROUND -6 C SUNDAY MORNING. THIS COULD RESULT IN A
SHORT PERIOD OF SNOW DOWN TO LAKE LEVEL IN THE TAHOE BASIN BEFORE
WARMER AIR MOVES IN DURING THE AFTERNOON.

THE LARGEST UNCERTAINTY WITH PRECIP POTENTIAL IS FOR MONDAY AND
MONDAY NIGHT. WHILE OPERATIONAL MODELS HAVE TRENDED TOWARD STALLING
THE MAIN LOW OFF THE CA COAST, SEVERAL ENSEMBLE MEMBERS STILL BRING
SIGNIFICANT MOISTURE INLAND DURING THIS TIME FRAME. IF THE 12Z GFS
AND ECMWF VERIFY, LITTLE OR NO RAIN OR SNOW WOULD OCCUR OVER THE
REGION, WHICH IS IN SHARP CONTRAST WITH THE PREVIOUS FORECAST. AT
THIS TIME THE PRECIP CHANCES WERE TRENDED DOWNWARD, ESPECIALLY SOUTH
OF HIGHWAY 50, BUT WE DID NOT GO DRASTICALLY LOWER YET BECAUSE OF
THE LARGE UNCERTAINTY AMONG THE MODEL GUIDANCE.

DEPENDING ON WHEN THE MAIN LOW FINALLY MOVES INLAND AND WHAT TRACK
IT TAKES, RAIN AND SNOW COULD BE A BETTER POSSIBILITY FOR TUESDAY
AND WEDNESDAY. HOWEVER, THE POTENTIAL FOR HEAVY PRECIP AMOUNTS IS
NOT A GUARANTEE, AS SOME OF THE MODEL SOLUTIONS WEAKEN THIS LOW AND
MOVE IT ACROSS SOUTHERN CA AND SOUTHERN NV, KEEPING THE BEST PRECIP
SOUTH OF OUR REGION. MJD

&&

.AVIATION...

VFR CONDITIONS WITH GENERALLY LIGHT WINDS EXPECTED THRU THANKSGIVING
DAY WITH AREAS OF HIGH CLOUDS SPREADING OVERHEAD. MORE ACTIVE
WEATHER PATTERN WITH INCREASING WINDS ARRIVES FRIDAY, WITH
PRECIPITATION CHANCES INCREASING SATURDAY AND SUNDAY. MJD

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&

$$

FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)







USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.