A moist but relatively warm west to east flow across the Pacific brought heavy high elevation snow to the Carson Range along with strong winds in the immediate lee of the Sierra.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS REV wrote it up.
A moist but relatively warm west to east flow across the Pacific brought heavy high elevation snow to the Carson Range along with strong winds in the immediate lee of the Sierra.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Reno, NV wrote its last area forecast discussion before the first event at Dec 21, 3:24 AM PST, 36 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
324 AM PST MON DEC 21 2015
.SYNOPSIS...
A WET STORM WILL IMPACT THE SIERRA AND NORTHWEST NEVADA TODAY AND
TUESDAY BRINGING SIGNIFICANT SNOW ACCUMULATION TO THE HIGH SIERRA.
AFTER A BRIEF BREAK WEDNESDAY, WHICH WILL BE THE BEST TRAVEL DAY
THIS WEEK IF NEEDING TO CROSS THE SIERRA BEFORE CHRISTMAS, ANOTHER
COLDER STORM WILL FOLLOW FOR CHRISTMAS EVE INTO CHRISTMAS DAY.
COLD AND DRY CONDITIONS WILL FOLLOW FOR THE WEEKEND WITH THE
POSSIBILITY OF ADDITIONAL WINTER WEATHER BY EARLY NEXT WEEK.
&&
.SHORT TERM...
THE WETTER TREND FOR THE TODAY INTO TUESDAY STORM, WHICH BEGAN
SHOWING UP IN FORECAST SIMULATIONS ABOUT 24 HOURS AGO, HAS
CONTINUED AND IF ANYTHING HAS EVEN GOTTEN A BIT WETTER. A
SIGNIFICANT PLUME OF MOISTURE IS BEING DRIVEN INTO THE NORTHWEST
BY A 150 KT JET BRINGING THE INGREDIENTS FOR COPIOUS AMOUNTS OF
PRECIPITATION AND STRONG AND GUSTY WINDS. 48-HOUR LIQUID TOTALS
ALONG THE WESTERN SIERRA CREST COULD EASILY REACH THE 4 TO 5 INCH
RANGE, TRANSLATING TO HEAVY SNOW ACCUMULATION IN THE HIGH SIERRA.
FOR ELEVATIONS BELOW 6500-7000 FEET, SNOW LEVELS ARE GOING TO BE
EXTREMELY TRICKY. DETAILS ON EACH PART OF THE SYSTEM ARE BROKEN UP
INTO SEGMENTS BELOW.
PRECIPITATION...
RADAR IS SHOWING PRECIPITATION RAPIDLY MOVING INTO THE REGION WITH
WEBCAMS AND OBSERVATIONS CONFIRMING SNOW FALLING ALONG THE WESTERN
SIERRA SLOPES INTO THE TAHOE BASIN EARLY THIS MORNING AS WELL AS
PORTIONS OF NORTHEAST CALIFORNIA. THE BROAD 1-1.5 INCH PWAT PLUME
WILL REACH THE SIERRA AND NORTHWEST NEVADA LATER THIS MORNING WITH
SEVERAL EMBEDDED WAVES IN THE FLOW ENHANCING THE PRECIPITATION
PRODUCTION. ELEVATIONS IN THE SIERRA ABOVE 7000 FEET COULD EASILY
SEE 1 TO 3 FEET OF SNOW BETWEEN THIS MORNING AND TUESDAY NIGHT,
WITH THE HIGHEST AMOUNTS LIKELY TO BE ALONG AND WEST OF HIGHWAY
89. THIS WILL CAUSE MAJOR TRAVEL DELAYS OVER SIERRA PASSES AND THE
INCREASED VOLUME OF TRAFFIC DUE TO THE HOLIDAYS WILL ONLY COMPOUND
THE EFFECTS. FOR THE TAHOE BASIN, THE SNOW AMOUNTS ARE GOING TO
BE HIGHLY DEPENDENT ON SNOW LEVELS. JUST A FEW HUNDRED FEET
DIFFERENCE COULD MEAN THE DIFFERENCE BETWEEN A COUPLE INCHES AND A
FOOT OF SNOW.
FOR NORTHEAST CALIFORNIA, THE SURPRISE VALLEY, AND NORTHERN WASHOE
COUNTY, THERE WILL BE DECENT AMOUNTS OF SPILLOVER WITH LIQUID
TOTALS GENERALLY IN THE 0.5 TO 1 INCH RANGE. THE HEAVIEST SNOW
TOTALS WILL BE ABOVE 5500 FEET WEST OF HIGHWAY 395, WITH LESSER
AMOUNTS TO THE EAST AND RAIN IN THE LOWEST ELEVATIONS. THIS IS
ALSO LIKELY TO BRING TRAVEL IMPACTS TO THESE AREAS THROUGH
TUESDAY.
WESTERN NEVADA WILL INITIALLY BE LARGELY SHADOWED, BUT THERE IS A
PERIOD TONIGHT INTO TUESDAY MORNING WHERE SPILLOVER LOOKS LIKELY.
LIQUID TOTALS FOR WESTERN NEVADA WILL GENERALLY BE IN THE
0.10-0.25 INCH RANGE WITH SNOW ACCUMULATION LIMITED TO ABOVE
6000-6500 FEET. IN THE HEAVIER PRECIPITATION BANDS, IT IS POSSIBLE
SNOW COULD MIX WITH RAIN AS LOW AS 5000 FEET, BUT IT WILL BE
SLUSHY WITH NO ACCUMULATION EXPECTED. HOWEVER, PLACES LIKE THE
VIRGINIA CITY HIGHLANDS COULD SEE UPWARDS OF 2 TO 5 INCHES OF
SNOW.
SNOW LEVELS...
WHILE WARMING TEMPERATURES ALOFT WOULD SUGGEST SNOW LEVELS RISING
TO THE 7000 FOOT RANGE, THE HEAVY PRECIPITATION IS LIKELY TO KEEP
SNOW LEVELS MUCH LOWER. FORECAST SOUNDINGS ARE INDICATING SNOW
LEVELS STAYING AROUND 5500-6000 FEET IN THE SIERRA, TAHOE BASIN,
AND NORTHEAST CALIFORNIA; WITH HIGHER SNOW LEVELS IN WESTERN
NEVADA DUE TO WINDS AHEAD OF THE SYSTEM MIXING THE VALLEYS OUT,
WARMING TEMPERATURES. FOR THE AREAS UNDER THE HEAVIEST
PRECIPITATION, IT IS LIKELY HOWEVER THE CHARACTER OF THE
PRECIPITATION BEGINS (RAIN OR SNOW), THAT IS HOW IT WILL STAY
UNTIL THE PRECIP LIGHTENS UP.
WIND...
STRONG AND GUSTY WINDS WILL ACCOMPANY THIS SYSTEM WITH 700 MB
WINDS INCREASING TO THE 60 TO 70 KT RANGE AND A DECENT SURFACE
GRADIENT IN PLACE. WHILE THERE IS SOME INDICATION OF A DOWNSLOPE
SIGNATURE IN THE LEE OF THE SIERRA, THE WIND PROFILE ALOFT AND
COPIOUS AMOUNTS OF MOISTURE ARE NOT INDICATIVE OF A TRUE DOWNSLOPE
EVENT. THAT BEING SAID, WINDS ARE STILL LIKELY TO GUST IN THE 50
TO 60 MPH RANGE IN VALLEY LOCATIONS WITH GUSTS EXCEEDING 100 MPH
IN THE SIERRA. THIS WILL LEAD TO TRAVEL RESTRICTIONS FOR HIGH
PROFILE VEHICLES, TURBULENCE AND MOUNTAIN WAVE ACTIVITY FOR
AVIATION, AND DANGEROUS CONDITIONS ON AREA LAKES.
BOTTOM LINE IS THIS...WE HAVE HIGH CONFIDENCE IS A VERY WET SYSTEM
WITH STRONG WINDS IMPACTING THE REGION OVER THE NEXT 36-48 HOURS.
HOWEVER, CONFIDENCE IN SNOW LEVELS AND THEREFORE SNOW TOTALS
BELOW 6500 FEET IS LOW. DJ
.LONG TERM...WEDNESDAY THROUGH SUNDAY...
MADE A FEW CHANGES TO THE LONG TERM, MAINLY TO COOL TEMPERATURES
FRIDAY/SATURDAY WITH THE VERY COLD AIR COMING IN BEHIND THE
CHRISTMAS EVE STORM. WEDNESDAY CONTINUES TO LOOK LIKE THE BEST
TRAVEL DAY AND HAVE CUT BACK ON PRECIPITATION CHANCES LEAVING ONLY A
FEW SHOWERS NORTH OF SUSANVILLE/GERLACH. MOISTURE REALLY THINS
BEHIND THE TUESDAY STORM SO DON'T SEE MUCH IN THE SIERRA AT ALL.
TEMPERATURES WILL ALSO START THEIR DOWNWARD TREND AND BE NEAR
AVERAGE.
MAIN FEATURE IS THEN THE CHRISTMAS EVE STORM. THE TREND FROM
YESTERDAY OF A FASTER/LESS MOIST STORM IS ON TRACK. IT WILL BE COLD
WITH SNOW LEVELS STARTING AT THE VALLEY FLOORS. THE BEST PERIOD FOR
SNOW LOOKS TO BE FROM 6 AM THROUGH 3 PM ON THURSDAY FROM NORTH TO
SOUTH. TOTAL QPF STILL LESS THAN AN INCH IN THE SIERRA WITH MAYBE UP
TO A 1/4" IN WESTERN NEVADA, BUT WITH THE COLD TEMPS, SNOW RATIOS
WILL AVERAGE 15:1 SO WE COULD SEE AROUND A FOOT ALONG THE CREST AND
A COUPLE INCHES IN WESTERN NEVADA.
THE STORM QUICKLY MOVES SOUTHEAST THURSDAY NIGHT WITH SNOW SHOWERS
RAPIDLY DIMINISHING. DEPENDING ON HOW QUICKLY SKIES CLEAR, FRIDAY
MORNING COULD BE QUITE A BIT COLDER THAN FORECAST. CHRISTMAS DAY
WILL BE COLD AS 700 MB TEMPS ARE -14 TO -16 C AND HIGHS WILL
STRUGGLE TO REACH FREEZING IN WRN NV AND REMAIN IN THE 20S IN THE
SIERRA. THEN, WITH CLEAR SKIES FRIDAY NIGHT, A VERY COLD NIGHT IS
IN STORE AND MAY BE THE COLDEST OF THE SEASON SO FAR. THE SIERRA
VALLEYS WILL BE COLD, BUT WESTERN NV VALLEYS WILL DEPEND ON HOW
MUCH SNOW FALLS CHRISTMAS EVE.
SHORT WAVE RIDGING IS THEN EXPECTED OVER THE WEEKEND WITH TEMPS
ALOFT RAPIDLY WARMING TO NEAR FREEZING AT RIDGE LEVEL. DEPENDING ON
SNOW COVER, VALLEY INVERSIONS COULD BE VERY STRONG WITH LITTLE IF
ANY WARMING IN WESTERN NEVADA WHILE MTN TEMPS RISE INTO THE 30S TO
LOW 40S. WALLMANN
&&
.AVIATION...
SIGNIFICANT IMPACTS ARE EXPECTED THE NEXT 36 HOURS FOR AREA
TERMINALS. THE NEXT MOIST STORM IS NOW MOVING IN WITH MVFR CONDS
ALREADY IN THE SIERRA. EXPECT KTRK/KTVL TO HAVE PREDOMINANT IFR
CONDS THRU 18Z TUE IN SN/RA. TIMING OF SNOW LEVEL RISING OFF
VALLEY FLOORS THERE DIFFICULT AND COULD OCCUR ANYWHERE FROM
00-12Z. THIS WOULD IMPACT RUNWAY ACCUMULATIONS WITH 4" AT THE LOW
END AND NEAR A FOOT AT THE HIGH END. CONFIDENCE REMAINS LOW ON
TIMING OF SNOW LEVELS RISING. IN ADDITION, EXPECT LLWS DUE TO WNW
WINDS ALOFT AT RIDGE LEVEL.
FOR KRNO/KCXP, MAIN IMPACTS WILL BE WIND AND LLWS TODAY. PEAK GUSTS
TO 40 KTS AT BOTH TERMINALS FROM THE SW. WINDS ALOFT ARE MORE 290,
SO EXPECT STRONG CROSS WINDS AND WIND SHEAR AOA 1500 FEET TODAY.
WINDS SHOULD WEAKEN AFT 03Z AS PRECIP BEGINS TO MOVE IN BUT LLWS
WILL STILL BE AN ISSUE. SOME MVFR CIGS/VIS POSSIBLE AFTER 06Z IN RA
FOR BOTH TERMINALS WITH PRECIP ENDING AFT 12Z TUE. WIND GUSTS TO 35
KTS POSSIBLE FROM THE WNW TUESDAY AFTERNOON WITH VFR CONDS.
CONFIDENCE HIGH ON LLWS/WINDS, BUT LOW ON PRECIP TIMING.
KMMH IMPACTS WILL BE MAINLY WIND AND WIND SHEAR INTO 06Z TONIGHT
BEFORE RA/SN AND MVFR CIGS/VIS BEGIN. IT WILL CONTINUE THROUGH AT
LEAST 18Z TUE. RUNWAY ACCUMULATIONS LOOK MINIMAL AS WE EXPECT IT
TO BE MORE RAIN THAN SNOW THERE.
BOTTOM LINE, CONDITIONS WILL BE FAIR TO POOR OVER THE NEXT 36 HOURS
IN THE SIERRA AND EXTREME WESTERN NEVADA. MAIN IMPACTS ARE LLWS,
WIND GUSTS TO 40 KTS AND IFR CIGS/VIS IN RA/SN. WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM PST
TUESDAY NVZ005.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 10 AM PST
TUESDAY NVZ002.
WIND ADVISORY FROM 9 AM THIS MORNING TO 10 PM PST THIS EVENING
NVZ003.
LAKE WIND ADVISORY FROM 9 AM THIS MORNING TO 5 PM PST THIS
AFTERNOON FOR PYRAMID LAKE IN NVZ004.
CA...WINTER STORM WARNING UNTIL 4 AM PST TUESDAY ABOVE 5500 FEET FOR
CAZ071.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM PST
TUESDAY CAZ070.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 PM PST
TUESDAY CAZ073.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 10 AM PST
TUESDAY CAZ072.
&&
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)The national radar mosaic for the moment the first event began.
1 heavy snow, 1 high wind. Local standard time, as filed.
One to two feet of snow fell above 7000 feet, including 18 inches at Daggett Pass. Up to 8 inches of snow fell down to around 6700 feet, with mainly rain below that level around Lake Tahoe.
Wind gusts of 60 to 65 mph were recorded along I-580 and highway 395 in the north valleys of Reno and in the Washoe and Carson Valleys. Winds were sustained over 40 mph for a time as well. Wind prone areas along I-580 south of Reno reported wind gusts between 73 and 88 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nevada in 2015Every state in 2015This day in weather historyWarnings in Nevada, December 2015
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 615376, 615377.