A fast moving winter storm brought up to a foot of snow above 5000 feet across the west side of the Sierra Nevada Mountains.
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 STO wrote it up.
A fast moving winter storm brought up to a foot of snow above 5000 feet across the west side of the Sierra Nevada Mountains.
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 Sacramento, CA wrote its last area forecast discussion before the first event at Dec 14, 4:25 AM PST, 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SACRAMENTO CA 425 AM PST TUE DEC 14 2010 .DISCUSSION... COLD FRONT BEGINNING TO MOVE INTO WRN SHASTA COUNTY AT PRESS TIME WITH THE LEADING EDGE OF THE FRONTAL BAND PRECIP EXTENDING FROM SRN LAKE COUNTY...EWD TO NEAR BLU. THE FRONT WILL BE SAGGING SWD OVER NORCAL TODAY AS UPPER LEVEL MOVES ACROSS THE PAC NW TODAY...AND THE UPPER LEVEL JET CURRENTLY ALONG THE CA/ORE BORDER ALSO SAGS SWD. BY 18Z...THE FRONT IS FORECAST TO SAG TO ABOUT THE REV/I-80 CORRIDOR WITH PCPN COVERING MOST...IF NOT ALL...OF OUR FORECAST AREA. BY 00Z WED THE FRONT WILL BE WELL S OF OUR AREA. BY MIDDAY...MODERATE TO HEAVY PCPN SHOULD BE AFFECTING MOST OF THE SIERNEV WHERE WE HAVE ALREADY HOISTED THE WINTER STORM WARNING FLAG. THE SHASTA DAM AND CHICO PROFILERS INDICATE 7-8 THOUSAND FOOT SNOW LEVELS AHEAD OF THE FRONT...WITH SNOW LEVELS FORECAST TO LOWER TO 3 TO 4.5 THOUSAND FEET BEHIND THE FRONT THIS EVENING. AFTER 06Z THE PCPN SHOULD BE WINDING DOWN IN THE SIERNEV AS THE DYNAMICS AND OROGRAPHICS ARE FORECAST TO WEAKEN BETWEEN THE 06-12Z WED TIME FRAME. MODEL QPFS SUGGEST OVER A HALF INCH IN THE NRN SAC VLY...TAPERING TO ABOUT .25 INCH NRN SAN JOAQUIN VLY...AND AT LEAST 1 TO 2 INCHES LIQUID IN THE SIERNEV WITH LOCALLY HIGHER AMOUNTS CORRELATING TO 12 TO 18 INCHES SNOW OVER THE HIGHER MTN PEAKS AND A LITTLE OVER A FOOT OVER THE MAJOR PASSES ON 80/50. SATELLITE IMAGERY SHOWS AN IMPRESSIVE PLUME OF MOISTURE MOVING ONSHORE AND EXTENDING WWD PAST 150W. BLENDED TPW SHOWS TWO PLUMES OVER AN INCH WHICH WILL LIKELY MERGE AND THEN DROP S OF THE AREA THIS EVENING WHICH WILL BRING AN END TO THE MODERATE TO HEAVY PCPN IN THE SIERNEV. UNTIL THEN...A CONSOLIDATED AREA OF ENHANCED CLOUDS EXTENDS FROM THE N COAST TO ABOUT 135W WHICH WILL BE AFFECTING NORCAL TODAY. THIS AREA HAS BEEN ENHANCED BY THE JET AND UPPER LEVEL DYNAMICS FROM THE UPPER LOW. THE LAST MAJOR SHORT WAVE ENERGY IS FORECAST TO ROTATE THRU THE AREA BY AROUND 06Z WED...AND AFTER WHICH...THE PCPN WILL DIMINISH. WEAK TROFFING OVER NORCAL ON WED BEHIND THIS SYSTEM MAY CONTINUE SOME ISOLATED SHOWERS MAINLY OVER THE SIERNEV AND COASTAL MTNS...BUT OTHERWISE IT WILL BE A CLOUDY DAY WITH CLEARING SKIES IN THE VALLEY DUE TO DRIER MID LEVEL FLOW AND CROSS MTN FLOW FROM THE COASTAL RANGE. SATELLITE IMAGERY SHOWS SOME CUMULIFORM CLOUDINESS BEHIND THE FRONT WHICH WILL BE OUR AIR MASS FOR WED. SCATTERED CUMULUS CLOUDS ARE POSSIBLE IN THE VALLEY WITH MORE OF A CEILING IN THE SIERNEV DUE TO THE UPSLOPE FLOW. WEAK RIDGING ON THU BUILDS INTO THE AREA WHICH MAY MEAN SOME STRATUS/FOG IN THE VALLEY. BUT THIS RIDGING WILL BE SHORT-LIVED AS ANOTHER DEEP GULF OF AK LOW IS FORECAST TO DEVELOP AND RETURN RAIN AND MOUNTAIN SNOW TO NORCAL BY LATE THU NITE AND INTO FRI. THIS LOW IS FORECAST TO DEEPEN OVER THE ERN PAC AND OFF THE CA COAST THRU THE MIDDLE OF NEXT WEEK WHICH MEANS A WET PATTERN IS IN STORE FOR NORCAL. COMPARED TO THE SCHEMATIC OF A LA NINA YEAR...THE BLOCKING HIGH OR OMEGA BLOCK IN THE UPCOMING PATTERN HAS BEEN SHIFTED FARTHER W...NEAR THE DATELINE INSTEAD OF THE GULF OF AK. THIS WILL ALLOW THE POLAR JET TO BRING COLDER AIR INTO NORCAL MEANING LOWER SNOW LEVELS WHICH WILL ALSO LESSEN THE FLOOD THREAT. JHM .EXTENDED DISCUSSION (FRIDAY NIGHT THROUGH TUESDAY)... A LARGE GULF OF ALASKA UPPER LEVEL LOW DROPS SOUTHWARD JUST OFF THE COAST ON FRIDAY NIGHT. THIS WILL BRING A VERY WET PATTERN THROUGH THE EXTENDED. MODELS ARE COMING INTO FAIRLY GOOD AGREEMENT NOW EVEN WITH THE TIMING FOR THIS EVENT. MODELS SHOW AN IMPRESSIVE PLUME OF PACIFIC MOISTURE AIMED INTO CENTRAL AND NRN CAL FOR LATE FRIDAY INTO SATURDAY...WITH A 1.25-1.5 PW PLUME PERPENDICULAR INTO THE SIERRA. THERE IS ALSO AMPLE DYNAMIC SUPPORT AS 130-150+ KT WEST TO EAST JET PUSHES OVER NRN CAL FRIDAY NIGHT INTO SATURDAY NIGHT. THE POTENTIAL IS THERE FOR ABUNDANT RAIN IN THE VALLEY AND HEAVY SNOWFALL IN THE MOUNTAINS...AS WELL AS GUSTY WINDS AT MOUNTAIN PASSES AND RIDGES. SNOW LEVELS FOR THE NORTHERN MOUNTAINS MAY DROP BELOW 4000 FEET AT TIME...AND AROUND 5000-5500 FEET IN THE NRN SIERRA. THERE MAY BE LITTLE BREAK FROM THIS PATTERN THROUGH AT LEAST TUESDAY AS JET STREAM REMAINS OVER NRN CAL. HOWEVER, WARMER AIR IS ENTRAINED INTO NRN CAL EARLY NEXT WEEK, RAISING SNOW LEVELS ABOVE 5500-6000 FEET IN THE SIERRA. I PLAYED IT MORE CONSERVATIVELY AS THE GFS WANTED TO GO HIGHER...ABOVE 7000 FEET BY TUESDAY. IN ANY CASE, ANYONE PLANNING TRAVEL OVER THE THIS WEEKEND AND EARLY NEXT WEEK SHOULD STAYED TUNED FOR FURTHER INFORMATION FOR THIS PROLONGED PRECIPITATION EVENT. JCLAPP && .AVIATION... PAC FRONT IMPACT INTERIOR NORCAL THIS MORN AND MOVING SLOWLY THRU TUE NIGHT. FOR CNTRL VALLEY...WIDESPREAD MVFR CIGS WITH LCL IFR CIGS LATE MORN/EARLY AFTN TO LATE AFTN TODAY. FOR MTNS...WIDESPREAD IFR IN NRN INTR MTNS WITH AREAS LIFR SPREADING FROM N TO S OVER THE SIERRA NEVADA THIS MORN. FREEZING LVLS OVER VALLEY NEAR FL090 WHILE LOWER OVER MTNS. SN LVLS MAINLY AT OR ABOVE 060 MSL THIS LOWERING TO 040 IN THE NRN MTNS AND AROUND 045-055 OVER SIERRA NEVADA THIS AFTN. JCLAPP && .STO WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 10 PM TUESDAY EVENING ABOVE 5000 FEET FOR THE WESTERN PLUMAS COUNTY/LASSEN PARK. WINTER STORM WARNING UNTIL 10 PM TUESDAY EVENING ABOVE 6000 FEET FOR THE WEST SLOPE NORTHERN SIERRA NEVADA. &&
2 winter storm. Local standard time, as filed.
Up to a foot of snow fell at Lassen Volcanic National Park and in the elevations above 5000 feet. Winds through the passes gusted up to 40 mph.
Up to a foot of snow fell in the backcountry and higher elevations. Up to four inches fell on I-80, with gusts to 40 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2010Every state in 2010This day in weather historyWarnings in California, December 2010
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: 275797, 275798.