An unusually cold winter storm dropped up to 12 to 24 inches of snow over the southern Cascade and northern Sierra Nevada mountains. Snow levels dropped to 1500 to 2500 feet in the latter half of the storm, bringing several inches of accumulation to the foothills of the western slope.
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.
An unusually cold winter storm dropped up to 12 to 24 inches of snow over the southern Cascade and northern Sierra Nevada mountains. Snow levels dropped to 1500 to 2500 feet in the latter half of the storm, bringing several inches of accumulation to the foothills of the western slope.
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 Mar 21, 8:10 AM PST, 3 hours 50 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SACRAMENTO CA 910 AM PDT SAT MAR 21 2009 .DISCUSSION... RAPID CHANGE IN THE WX OVER INTERIOR NORCAL THIS WEEKEND AFTER A COUPLE OF DELIGHTFUL SPRING DAYS. EVEN THO SPRING HAS OFFICIALLY BEGUN...NATURE WILL THROW A RATHER POWERFUL WINTER STORM AT NORCAL...COMING IN 2 PARTS. THE INITIAL SHORT WAVE IS CURRENTLY OFF THE CA COAST AND WILL BE ROTATING INLAND LATER THIS AFTERNOON. MORNING RAOBS SHOWED POSITIVE LIS OVER MFR/OAK...BUT NEGATIVE AT REV. MORNING RADAR INDICATED ISOLATED TRW W OF BURNEY AND S OF YOSEMITE INDICATIVE OF THE MORE UNSTABLE AIR OVER THE MTNS. THE AIR MASS IS INITIALLY QUITE DRY WITH PWS NO MORE THAN .50 INCHES SO PCPN AHEAD OF THE SHORT WAVE WILL BE MEAGER. BUT CLOUD ENHANCEMENT OFF THE COAST ALONG THE INITIAL SHORT WAVE INDICATES PCPN RATES SHOULD BE INCREASING AS THIS PART OF THE STORM MOVES INLAND LATE AFTERNOON AND EARLY EVENING. BEHIND THE INITIAL SHORT WAVE...COMES THE 2ND AND MORE POWERFUL PUNCH LATER TONIGHT AND INTO SUN. SATELLITE INDICATES A LARGE AREA OF OPEN/CLOSED CELLULAR CUMULUS UNDER A VERY COLD POOL OF AIR THAT WILL BE ROTATING INLAND AFTER 06Z SUN...AND INTO SUN. THE STRONGEST Q-VECTOR CONVERGENCE AND LARGE SCALE ASCENT SHOULD BE MOVING ACROSS INTERIOR NORCAL FROM JUST BEFORE 06Z SUN THRU A LITTLE AFTER 18Z SUN. STRONG JET DYNAMICS WILL ALSO BE KICKING IN AROUND 06Z AS NORCAL WILL BE N OF THE UPPER JET AND IN THE INDIRECT CIRCULATION OF THE UPPER JET OVERNITE WITH INCREASING UPWARD MOTION. A STRONG COLD FRONT WILL BE MOVING INTO THE AREA BETWEEN 06Z-12Z SUN...AND THIS WILL LIKELY ACT AS A FOCUS FOR HEAVY SHOWERS/THUNDERSTORMS AS THE AIR MASS RAPIDLY COOLS AND DESTABILIZES. THIS PATTERN LOOKS FAVORABLE FOR A NICF /COLD FRONTAL RAIN BAND/ TO DEVELOP ALONG WITH SOME STRONG STORMS...MAINLY EARLY SUN AS THE TROF AXIS IS JUST OFF THE COAST...LEADING TO BACKING SURFACE WINDS AHEAD OF THE FRONTAL BOUNDARY. THIS WOULD RESULT IN FAVORABLE WIND SHEAR PROFILES FOR ROTATING STORMS ON SUN...THROUGH MIDDAY SUN. HOWEVER...INSTABILITY WILL CONTINUE OVER THE AREA ALL DAY DUE TO THE COLD POOL ALOFT. THUS...WE COULD SEE THUNDER LAST VIRTUALLY THROUGH MUCH OF THE DAY. GIVEN THE CONVECTIVE NATURE OF THIS EVENT...RAINFALL QPFS ARE LIKELY TO VARY WIDELY. THE 5H COLD POOL IS FORECAST TO MOVE OVER INTERIOR NORCAL LATE TONIGHT AND SUN WITH TEMPS MINUS 28-32 DEG C. 7H TEMPS ARE ALSO FORECAST TO LOWER TO MINUS 12-14 DEG C BY EARLY SUN. THIS WOULD LOWER SNOW LEVELS TO THE 1500 TO 2500 FOOT LEVEL...AND GIVEN THE QPF FOR THE NRN MTNS AND SIERNEV FOOTHILLS...WE ARE CONTEMPLATING WINTER WX ADVSRYS FOR 13/68...AND A WINTER STORM WARNING FOR THE MOTHERLODE ZONE 67. THE POSSIBILITY OF THUNDER SNOW COULD RESULT IN RAPID SNOW ACCUMULATIONS. THE PROGS HAVE THIS SYSTEM MOVING E OF INTERIOR NORCAL SUN EVENING...WITH SHORT WAVE RIDGING BUILDING IN ON MON. JHM .EXTENDED (MON NIGHT THROUGH SATURDAY)... NUMERICAL MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH MOST OF THE EXTENDED PERIOD WITH A DIRTY RIDGE OF HIGH PRESSURE DOMINANT OVER INTERIOR NORTHERN CALIFORNIA. THE ONLY WEATHER FEATURE OF NOTE WILL BE AN ELONGATED SHORTWAVE THAT WILL QUICKLY MOVE APPROACH THE AREA WEDNESDAY. LATEST RUNS HAVE BEEN KEEPING THIS SYSTEM TO THE NORTH AND EAST OF THE AREA...MOST LIKELY KEEPING PRECIPITATION TO THE EAST OF THE SIERRA CREST. OTHERWISE A GRADUAL WARMING TREND WILL BE IN THE WORKS AS SURFACE HIGH PRESSURE SETTLES INTO THE GREAT BASIN TOWARDS THE END OF THE WEEK AND PUSHES HIGH TEMPERATURES WELL ABOVE NORMAL. NORTH TO NORTHEASTERLY OFFSHORE FLOW WILL DEVELOP IN RESPONSE TO THE GREAT BASIN HIGH BRINGING POSSIBLY GUSTY CONDITIONS THURSDAY INTO FRIDAY...THOUGH THE TIMING ON THIS HAS BEEN SHIFTING. DANG && .AVIATION... A COLD FRONT WILL USHER IN MOUNTAIN SNOWS...VALLEY RAINS AND SOME THUNDERSTORMS DURING THE NEXT 24 HRS. VFR CONDITIONS WILL GRADUALLY DETERIORATE AS THE FRONT NEARS THE REGION THIS AFTERNOON. PRIOR TO THIS...A FEW ISOLATED THUNDERSHOWERS MAY DEVELOP. THESE STORMS WILL MOVE ENE AS THEY DEVELOP. EXPECT GENERALLY VFR CIGS TO SAG TO MVFR IN THE NORTH AROUND 00Z AND ABOUT FOUR TO SIX HOURS LATER ALONG THE SOUTHERN SACRAMENTO VALLEY. LOWER CIGS AND VIS ARE LIKELY IN SNOW OR HEAVIER RAIN SHOWERS. SNOW LEVELS WILL BEGIN AROUND 5000 FT THIS MORNING AND DROP AS LOW AS 2000 FT OVERNIGHT BREEZY S TO SW WINDS AHEAD OF THE FRONT WILL PRODUCE LOCAL GUSTS TO 30 KT IN THE VALLY DURING THE AFTERNOON AND EVENING...WITH STRONGER GUSTS TO 45KT AROUND RIDGETOPS AND NEAR CHANNELED AREAS OF HIGHER TERRAIN. DK2 && .STO WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING FOR WESTERN PLUMAS COUNTY AND LASSEN PARK FROM 4 PM TODAY THROUGH 9 AM SUNDAY MORNING. WINTER STORM WARNING FOR THE WESTERN SLOPES OF THE SIERRA NEVADA FROM 4 PM TODAY THROUGH 4 PM SUNDAY AFTERNOON. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SACRAMENTO CA 700 AM PDT SAT MAR 21 2009 CAZ013>019-063-064-066>069-221400- SHASTA LAKE AREA/NORTHERN SHASTA COUNTY- BURNEY BASIN/EASTERN SHASTA COUNTY-NORTHERN SACRAMENTO VALLEY- CENTRAL SACRAMENTO VALLEY-SOUTHERN SACRAMENTO VALLEY- CARQUINEZ STRAIT AND DELTA-NORTHERN SAN JOAQUIN VALLEY- MOUNTAINS SOUTHWESTERN SHASTA TO NORTHERN LAKE COUNTIES- CLEAR LAKE/SOUTHERN LAKE COUNTY-MOTHERLODE- EAST FOOTHILLS/NORTH SACRAMENTO VALLEY- WESTERN PLUMAS COUNTY/LASSEN PARK-WEST SLOPE NORTHERN SIERRA NEVADA- 700 AM PDT SAT MAR 21 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR INTERIOR NORTHERN CALIFORNIA. .DAY ONE...TODAY A WINTER STORM WILL MOVE INTO THE REGION LATER TODAY. SOME LIGHT SHOWERS MAY DEVELOP AHEAD OF THE FRONT LATER THIS MORNING AND AFTERNOON AHEAD OF THE MAIN PART OF THE SYSTEM THAT WILL BRING WITH IT HEAVY SNOW AT TIMES OVERNIGHT IN THE MOUNTAINS. THUNDERSTORMS WILL BE POSSIBLE TODAY OVER THE NORTHERN HALF OF THE VALLEY AND SURROUNDING FOOTHILLS AND THEN OVER THE ENTIRE REGION OVERNIGHT. SOME HEAVY PRECIPITATION MAY OCCUR OVERNIGHT AS THE FRONT MOVES THROUGH THE REGION. SEE WINTER STORM WARNING AND SPECIAL WEATHER STATEMENT FOR MORE DETAILS. * WINTER STORM WARNING.......SEE WWUS46 KSTO - WSWSTO FOR DETAILS * * SPECIAL WEATHER STATEMENT..SEE WWUS86 KSTO - SPSSTO FOR DETAILS * .DAYS TWO THROUGH SEVEN... SUNDAY THROUGH FRIDAY LOW SNOW LEVELS WILL START THE DAY WITH SNOW ACCUMULATING IN THE FOOTHILLS. THE THREAT OF THUNDERSTORMS WILL ALSO PERSIST BUT SHIFT SOUTH AND EAST OVER THE AREA DURING THE DAY. BEYOND SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. * WINTER STORM WARNING.......SEE WWUS46 KSTO - WSWSTO FOR DETAILS * * SPECIAL WEATHER STATEMENT..SEE WWUS86 KSTO - SPSSTO FOR DETAILS * .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS TO THEIR LOCAL NATIONAL WEATHER SERVICE OFFICE. THE LATEST WEATHER INFORMATION IS AVAILABLE ON THE INTERNET AT (LOWER CASE): HTTP://WWW.WRH.NOAA.GOV/STO
3 winter storm. Local standard time, as filed.
Snow amounts up to 10 inches were reported over the higher elevations of Shasta County.
Up to 18 inches of heavy snow were reported in Lassen Volcanic National Park.
Ten to thirty inches of heavy snow were reported over the higher elevations and at ski resorts. Gusty winds and blowing snow caused additional travel problems on Interstate 80 and Highway 50.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2009Every state in 2009This day in weather historyWarnings in California, March 2009
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: 154904, 154717, 154899.