Winter Storm and Heavy Snow in Nevada, January 30 to 31, 2016

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
302 PM PST SAT JAN 30 2016

.SYNOPSIS...

ANOTHER WINTER STORM WILL PUSH THROUGH THE REGION TONIGHT THROUGH
SUNDAY NIGHT, BRINGING ADDITIONAL SNOW AMOUNTS TO THE SIERRA AND
VALLEYS OF WESTERN NEVADA. WINDS WILL INCREASE SUNDAY NIGHT
ESPECIALLY SOUTH OF HIGHWAY 50. BE PREPARED FOR TRAVEL IMPACTS
TONIGHT AND INTO MONDAY MORNING.

&&

.SHORT TERM...

THE ATMOSPHERIC RIVER STORM THAT AFFECTED THE REGION IS NOW
EXITING WESTERN NEVADA, AFTER LEAVING MANY AREAS WITH SNOWFALL
THIS MORNING. SNOW LEVELS CAME DOWN PRETTY FAST THIS MORNING
BEHIND THE COLD FRONT, WITH SNOWFALL AMOUNTS UP TO 4 TO 5 INCHES
AROUND THE FERNLEY-FALLON-YERINGTON AREAS. ELSEWHERE IN WESTERN
NEVADA, MOST LOCATIONS GOT LESS THAN 2 INCHES. STORM TOTAL
RAINFALL AMOUNTS IN THE SIERRA HAVE BEEN IMPRESSIVE, WITH AROUND 3
TO 5 INCHES WEST OF HIGHWAY 89 IN THE TAHOE BASIN AND UP INTO
PLUMAS COUNTY.

A FEW SHOWERS ARE DEVELOPING OVER NORTHEAST CA AND NORTHERN NEVADA
THIS AFTERNOON UNDER THE UNSTABLE CONDITIONS ALOFT. TONIGHT AND
INTO SUNDAY, THE NEXT SHORTWAVE MOVES INTO THE CENTRAL CA COAST,
WITH ANOTHER ROUND OF WINTER WEATHER FOR OUR REGION. THE JET DIVES
INTO SOUTHERN CA SUNDAY, WHICH WILL TAKE THE BRUNT OF THE PACIFIC
MOISTURE WELL SOUTH OF OUR AREA, BUT ALSO DRIVE COLDER AIR INTO
OUR AREA WITH STRONG INSTABILITY. A SURFACE LOW WILL DEVELOP IN
SOUTHERN NEVADA, A HYBRID "TONOPAH LOW", BRINGING GOOD WRAP-
AROUND BANDED PRECIPITATION OUR AREA. THE ONLY PROBLEM WITH THIS
BANDED PRECIPITATION IS THAT THE LOCATION IS VERY DIFFICULT TO
PINPOINT, LEADING TO LOWER FORECASTER CONFIDENCE TO WHERE THE
HEAVIEST SNOW OCCURS.

WE HAVE ISSUED WINTER WEATHER ADVISORIES STARTING TONIGHT THROUGH
SUNDAY NIGHT. IN GENERAL, MOST AREAS WILL BE CAPABLE OF GETTING 3
TO 6 INCHES MAINLY SOUTH OF INTERSTATE 80. LOCALIZED HIGHER
AMOUNTS OF SNOW UP TO 8 INCHES MAY BE POSSIBLE UNDER THE HEAVIER
BANDS. IN THE LAKE TAHOE BASIN AND EASTERN SIERRA OF ALPINE AND
MONO COUNTY, WE COULD SEE SNOW AMOUNTS OF 4-8 INCHES WITH UP TO 12
INCHES ABOVE 7000 FEET. NORTH TO NORTHEAST FLOW WILL BE FAVORABLE
FOR SEEING ENHANCED UPSLOPE PRECIPITATION. DURING THE AFTERNOON ON
SUNDAY, SNOW WILL PROBABLY MELT OFF SOME OF THE ROADS, THEN BECOME
SLICK AGAIN SUNDAY EVENING AFTER THE SUN GOES DOWN.

LASTLY, AS THE HYBRID "TONOPAH LOW" STARTS TO DEEPEN SUNDAY NIGHT
OVER SOUTHERN NEVADA, INCREASING THE PRESSURE GRADIENTS ACROSS
OUR AREA. WE'VE TRENDED THE WINDS STRONGER FOR MUCH OF THE AREA. THESE
WINDS MAY PRODUCE NEAR WHITEOUT CONDITIONS SUNDAY NIGHT ESPECIALLY
AREAS SOUTH OF HIGHWAY 50 IN MONO AND MINERAL COUNTIES AND INTO
THE HIGH SIERRA.

ANYONE WITH TRAVEL PLANS OR BACKCOUNTY PLANS TONIGHT THROUGH
SUNDAY NIGHT SHOULD BE PREPARED FOR WINTER DRIVING CONDITIONS. IF
YOU HAVE TRAVEL PLANS SUNDAY NIGHT BE AWARE OF THE POTENTIAL OF
DANGEROUS WHITEOUT CONDITIONS, ESPECIALLY SOUTH OF HIGHWAY 50.
SLICK AND ICY ROAD CONDITIONS WILL LIKELY CONTINUE INTO MONDAY AS
WELL. A SLIGHT CHANCE OF SNOW SHOWERS RETURNS FOR AREAS NORTH OF
HIGHWAY 50 ON MONDAY AS A WEAK WAVE MOVES THROUGH THE REGION, BUT
LITTLE TO NO ACCUMULATIONS ARE EXPECTED. HOON

.LONG TERM...TUESDAY THROUGH SATURDAY...

NO MAJOR CHANGE WAS MADE TO THE ONGOING FORECAST AS A GENERALLY
QUIET WEATHER PATTERN IS EXPECTED FOR THE UPCOMING WEEK. WHILE
MOST MEDIUM RANGE GUIDANCE KEEPS A RIDGE AXIS NEAR THE SIERRA AND
WESTERN NV FOR MUCH, WEAK SHORTWAVES MOVING ACROSS THE WESTERN
U.S. WILL BRING AREAS OF CLOUD COVER AND POSSIBLE LIGHT SHOWERS AT
TIMES.

THE FIRST OF THESE WEAK WEATHER SYSTEMS APPEARS TO BE ON TRACK TO
BRUSH ACROSS THE SIERRA AND FAR WESTERN NV DURING THE DAY TUESDAY,
THEN EXITING MONO AND MINERAL COUNTY TUESDAY EVENING. FORCING DOES
NOT APPEAR VERY STRONG AND MOISTURE WILL BE SHALLOWER, PRODUCING
LIMITED SNOWFALL TOTALS, WITH SIGNIFICANT TRAVEL IMPACTS UNLIKELY.

LATER IN THE WEEK, THE TIMING AND TRACK FOR SUBSEQUENT SHORTWAVE
PASSAGES BECOME MORE UNCERTAIN, SO OVERALL FORECAST CONFIDENCE IN
PRECIP CHANCES IS BELOW AVERAGE. SOME GUIDANCE SCENARIOS KEEP ALL OF
EASTERN CA-WESTERN NV DRY, WHILE OTHERS BRING 1 OR 2 WEAK SHORTWAVE
PASSAGES BETWEEN WEDNESDAY AND SATURDAY, MAINLY NORTH OF SUSANVILLE-
GERLACH. NONE OF THESE ARE EXPECTED TO BE MAJOR PRECIPITATION
EVENTS. LIGHT WINDS WILL PREVAIL FOR MUCH OF NEXT WEEK, WITH
POTENTIAL FOR SOME INVERSION CONDITIONS BRINGING MINOR AIR QUALITY
ISSUES IN URBAN AREAS AT TIMES WED-SAT. MJD

&&

.AVIATION...

THROUGH THIS EVENING, VFR CONDS ARE LIKELY TO PREVAIL BUT BANDS OF
CLOUDS AND SNOW SHOWERS WILL LIKELY OBSCURE HIGHER TERRAIN NEAR THE
MAIN TERMINALS. IF ANY OF THESE BANDS MOVE OVER TERMINAL SITES THEN
CIGS/VSBY WOULD QUICKLY DROP TO IFR/LIFR. PATCHY FOG IS ALSO
POSSIBLE ESPECIALLY AFTER HEAVIER SNOW SHOWERS TAPER OFF.

ANOTHER ROUND OF SNOW/SNOW SHOWERS IS LIKELY TO DEVELOP LATE TONIGHT
AND CONTINUE THROUGH SUNDAY AND SUNDAY NIGHT WITH IFR OR WORSE
CIGS/VSBY. NOT ALL AREAS WILL HAVE CONTINUOUS SNOW, BUT COULD
RECEIVE HEAVIER CONVECTIVELY ENHANCED SNOW BANDS PERSISTING FOR 1-3
HOURS. SNOW ACCUMULATIONS OF 2 OR MORE INCHES ON RUNWAYS ARE LIKELY
AT ALL MAIN TERMINALS (WHICH MAY MELT DURING THE DAY IF SNOW IS
LIGHT), WITH POSSIBLY UP TO 6 INCHES ESPECIALLY NEAR THE SIERRA. THE
MOST LIKELY TIMES FOR SNOW ACCUMULATIONS IN LOWER ELEVATIONS ARE
SUNDAY MORNING, THEN AGAIN FROM LATE SUNDAY AFTERNOON AND EVENING
BETWEEN 3 AND 8 PM. MJD

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST
     MONDAY NVZ002.

     WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST
     MONDAY NVZ001-003-004.

CA...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST
     MONDAY CAZ071.

     WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST
     MONDAY CAZ073.

     WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST
     MONDAY CAZ072.

&&

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