A cold winter storm dropped significant snowfall amounts over Northwest California. This resulted in chain restrictions on the higher elevation roads.
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 EKA wrote it up.
A cold winter storm dropped significant snowfall amounts over Northwest California. This resulted in chain restrictions on the higher elevation roads.
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 Eureka, CA wrote its last area forecast discussion before the first event at Mar 18, 3:23 AM PST, 37 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE EUREKA CA 423 AM PDT FRI MAR 18 2011 .SYNOPSIS...THE WET AND COLD PATTERN CONTINUES INTO THE WEEKEND AS A LARGE STORM SYSTEM LINGERS OFFSHORE. DISCUSSION...FRONT GOING THROUGH OVERNIGHT WITH SIGNIFICANT LINE OF THUNDERSTORMS MOVING THROUGH COASTAL WATERS BUT ACTIVITY RAPIDLY DECREASED AS IT APPROACHED THE MAINLAND. BUOYS SHOWED WIND SHIFT FROM SE TO SW WITH FRONTAL PASSAGE AND TEMPS DROPPED 4-6 DEGREES. ADDED MODERATE PRECIPITATION WITH THE LINE AS IT MOVES THROUGH THIS MORNING BUT OTHERWISE NO SIGNIFICANT CHANGES FOR TODAY AND THROUGH THE WEEKEND. NSSL HAS SNOW LEVEL AROUND 3800 FEET WHICH MAY BE A FEW HUNDRED FT LOW GIVEN THE MESOWEST OBS. IT DOES SHOW LOWER SNOW LEVELS FURTHER WEST BEHIND THE FRONT WITH VALUES NEAR 2900 FEET. AS COLD AIR FILTERS IN BEHIND FRONT...SNOW LEVELS WILL DROP AND LEFT WINTER STORM WARNING AT 2500 FEET. IN BIGGER PICTURE...UPPER LEVEL LOW 500 MILES W OF PORTLAND WILL GRADUALLY SAG SOUTHWEST TO OFF OF THE MENDOCINO COAST BY SUN AFTERNOON. HEAVIEST PCPN WILL BE TODAY ASSOCIATED WITH FRONT AND SHORT WAVE ROTATING THROUGH AREA. MODELS DO NOT SHOW THE SECONDARY LOW DEVELOPING ON THE SOUTH SIDE OF THE MAIN LOW BUT RATHER JUST AN OPEN TROUGH. MODELS HAVE MAIN IDEA OF SHIFTING LOW INLAND LATE SUNDAY NIGHT OR MON. BUMPED UP POPS IN MENDOCINO COUNTY FOR SUN AS LOW APPROACHES. AIRMASS IS STILL UNSTABLE AND CONTINUED CONVECTION INTO SATURDAY. FOR NEXT WEEK...BRIEF BREAK IN RAIN ABOUT TUESDAY THOUGH COULD STILL HAVE A FEW SHOWERS. ANOTHER LOW APPROACHES WED FROM THE PACIFIC WITH BOTH GFS AND EC HAVING IT ABOUT 36N 130W AND GEM FASTER WITH AN OPEN TROUGH. THIS LOW MOVES INLAND WITH SPECIFIC TIMING IN QUESTION BUT SOMEWHERE IN THE WED...WED NIGHT TIME FRAME. YET ANOTHER LOW DROPS DOWN FROM THE GULF OF ALASKA ABOUT THU. AGAIN MODELS DIFFER IN TIMING AND STRENGTH BUT STILL HAVE MOIST SOUTHWEST FLOW SHOWED CONTINUED WITH POPS IN THE 50-60 PERCENT VALUES AS SHOWED GET SOME RAIN. DEAN && .AVIATION...MORNING IR SAT SHOWS OPEN CELL CU MOVING INTO NW CALIFORNIA TODAY. THIS WILL ALLOW FOR VFR TO DOMINATE THE DAY, BUT SHOWERS AND THUNDERSTORMS WILL REMAIN A THREAT. DURING CONVECTIVE CONDITIONS, VFR WILL FALL TO IFR AS WELL AS BRING GUSTY WINDS AND POSSIBLE LIGHTNING. SO IN TOTAL, IT WILL BE A MIXED BAG TODAY ACROSS NW CALIFORNIA WITH A COLD UNSTABLE AIR MASS POOLING IN. BFG && .MARINE...WINDS ARE DIMINISHING IN THE WAKE OF THE FRONT OVERNIGHT. HOWEVER, POST FRONTAL SWELL IS BEGINNING TO BUILD IN TO THE WATERS. THE EARLY MORNING BUOY REPORTS ARE SHOWING BUILDING SEAS. W SWELL SHOULD PEAK AROUND 17 FT OFFSHORE AND 15 FT NEAR SHORE. THIS WILL BE RELATIVELY SHORT PERIOD SWELL, WITH PERIODS OF 12 TO 14 SECONDS. AS SUCH, A HAZ SEAS WARNING HAS BEEN ISSUED THROUGH SAT MORNING. THE OUTER WATERS WILL ALSO CONTINUE TO HAVE LOW END SMALL CRAFT ADVISORY WINDS THROUGH SAT EVENING. CONDITIONS WILL COME DOWN SAT NIGHT AS THE GRADIENT RELAXES AND THE SWELL FADES. N OF THE CAPE WILL REMAIN GENERALLY FAIR INTO EARLY NEXT WEEK, BUT S OF THE CAPE WILL TELL A DIFFERENT STORY. AN AREA OF LOW PRESSURE WILL SLIP BY THE SRN OUTER WATERS ON SUN, CAUSING AN INCREASE IN WINDS AND SEAS S OF SHELTER COVE AND MORE TOWARD FORT BRAGG AND POINT ARENA. THESE WINDS WILL BE OFFSHORE WINDS AND COULD PRODUCE GALE CONDITIONS FOR THE OUTER WATERS. THE 00Z MODEL SUITE IS IN GOOD AGREEMENT WITH THIS SOLUTION, SO THE FORECAST HAS BEEN ADJUSTED TO REFLECT SUCH. AS THE LOW DROPS PAST, WINDS WILL AGAIN TAKE A NORTHERLY FORM. DURING LOW PASSAGE, OFFSHORE WINDS WILL PREVAIL ALL ALONG THE COAST. THIS IS EXPECTED TO LAST FROM SUN NIGHT INTO MON. A LONG PERIOD W SWELL WILL BUILD INTO THE REGION BY MON, BUT MAY BE CONTAMINATED BY A SOUTHERLY SWELL GENERATED BY THE PASSING LOW. WE WILL HAVE TO SEE HOW MODELS CONTINUE TO HANDLE THIS PATTERN OVER THE NEXT FEW DAYS. BFG && .EKA WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 6 PM PDT TODAY ABOVE 2500 FEET FOR THE CAZ003-004-076. HAZARDOUS SEAS WARNING IN EFFECT UNTIL 9 AM SATURDAY PZZ470-475-450 SMALL CRAFT ADVISORY IN EFFECT UNTIL 9 PM SATURDAY PZZ470-475-455 && VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE EUREKA CA 321 PM PDT THU MAR 17 2011 CAZ001-002-182230- REDWOOD COAST-MENDOCINO COAST- 321 PM PDT THU MAR 17 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST CALIFORNIA. .DAY ONE...THIS AFTERNOON AND TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED TONIGHT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. ISOLATED THUNDERSTORMS ARE EXPECTED FRIDAY AFTERNOON THROUGH SATURDAY. SMALL HAIL WILL BE THE PRIMARY THREAT WITH ANY THUNDERSTORMS. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER TO THE NATIONAL WEATHER SERVICE IN EUREKA. CAZ003-004-076-182230- NORTH COAST INTERIOR-UPPER TRINITY RIVER-MENDOCINO INTERIOR- 321 PM PDT THU MAR 17 2011 ...WINTER STORM WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 6 PM PDT FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST CALIFORNIA. .DAY ONE...THIS AFTERNOON AND TONIGHT. A WINTER STORM WARNING IS CURRENTLY IN EFFECT. FOR FURTHER DETAILS PLEASE REFER TO NOAA WEATHER RADIO OR WEATHER.GOV/EUREKA. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. A WINTER STORM WARNING IS CURRENTLY IN EFFECT THROUGH FRIDAY AFTERNOON. ISOLATED THUNDERSTORMS ARE ALSO POSSIBLE FRIDAY AFTERNOON THROUGH SATURDAY...WITH THE PRIMARY THREAT BEING SMALL HAIL. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER TO THE NATIONAL WEATHER SERVICE IN EUREKA.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
138 AM PDT FRI MAR 18 2011
CAZ001>003-180930-
DEL NORTE CA-HUMBOLDT CA-MENDOCINO CA-
138 AM PDT FRI MAR 18 2011
THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
EXTREME NORTHWESTERN MENDOCINO COUNTY IN NORTHWEST CALIFORNIA
WESTERN HUMBOLDT COUNTY IN NORTHWEST CALIFORNIA
DEL NORTE COUNTY IN NORTHWEST CALIFORNIA
UNTIL 230 AM PDT
AT 133 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 6 MILES WEST OF
SMITH RIVER TO 16 MILES WEST OF FORTUNA TO 47 MILES WEST OF FORT
BRAGG..AND MOVING NORTHEAST AT 30 MPH.
WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THESE STORMS...ALONG WITH
OCCASIONAL LIGHTNING AND SMALL HAIL.
THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.
LAT...LON 4190 12357 4182 12368 4168 12365 4159 12370
4150 12363 4000 12389 3999 12395 3996 12391
3990 12393 4002 12407 4008 12408 4025 12436
4042 12440 4097 12412 4113 12416 4137 12406
4171 12414 4179 12425 4200 12420 4200 12357
TIME...MOT...LOC 0837Z 247DEG 25KT 4193 12422 4065 12440
3938 12464
BFGSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
223 AM PDT FRI MAR 18 2011
CAZ001-003-004-181000-
HUMBOLDT CA-
223 AM PDT FRI MAR 18 2011
THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
HUMBOLDT COUNTY IN NORTHWEST CALIFORNIA
UNTIL 300 AM PDT
AT 220 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM ARCATA TO
HONEYDEW..AND MOVING NORTHEAST AT 40 MPH.
IN ADDITION TO WIND GUSTS UP TO 40 MPH... THESE STORMS MAY PRODUCE
SMALL HAIL AND OCCASIONAL LIGHTNING.
THESE STORMS MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
AND TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.
LAT...LON 4083 12419 4102 12409 4124 12366 4052 12360
4009 12370 4005 12401 4021 12430
TIME...MOT...LOC 0922Z 231DEG 37KT 4093 12401 4028 12404SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE
302 AM PDT FRI MAR 18 2011
CAZ001>004-076-181045-
TRINITY CA-DEL NORTE CA-HUMBOLDT CA-MENDOCINO CA-
302 AM PDT FRI MAR 18 2011
THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
MENDOCINO COUNTY IN NORTHWEST CALIFORNIA
HUMBOLDT COUNTY IN NORTHWEST CALIFORNIA
DEL NORTE COUNTY IN NORTHWEST CALIFORNIA
TRINITY COUNTY IN NORTHWEST CALIFORNIA
UNTIL 345 AM PDT
AT 257 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 12 MILES WEST OF
ORLEANS TO GUALALA..AND MOVING EAST AT 30 MPH.
IN ADDITION TO WIND GUSTS UP TO 40 MPH... THESE STORMS MAY PRODUCE
SMALL HAIL AND OCCASIONAL LIGHTNING.
LAT...LON 3892 12373 3903 12369 3934 12382 3956 12376 3982
12384 4008 12408 4025 12436 4046 12440
4097 12412 4113 12416 4137 12406 4150 12408
4152 12363 4138 12364 4138 12350 4118 12340
4107 12314 3880 12313 3875 12352
TIME...MOT...LOC 0959Z 257DEG 25KT 4137 12372 3938 12409SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE
349 AM PDT FRI MAR 18 2011
CAZ002-003-076-181130-
HUMBOLDT CA-MENDOCINO CA-
349 AM PDT FRI MAR 18 2011
THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
MENDOCINO COUNTY IN NORTHWEST CALIFORNIA
HUMBOLDT COUNTY IN NORTHWEST CALIFORNIA
TRINITY COUNTY IN NORTHWEST CALIFORNIA
UNTIL 430 AM PDT
AT 344 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM SHELTER COVE TO
POINT ARENA..AND MOVING NORTHEAST AT 15 MPH.
IN ADDITION TO WIND GUSTS UP TO 40 MPH... THESE STORMS MAY PRODUCE
SMALL HAIL AND OCCASIONAL LIGHTNING.
LAT...LON 3892 12373 3907 12370 3934 12382 3955 12376
3970 12379 3983 12385 4002 12407 4007 12403
4015 12413 4019 12412 4001 12315 3881 12319
3880 12335 3877 12337 3875 12352
TIME...MOT...LOC 1048Z 211DEG 14KT 4011 12389 3857 124363 heavy snow. Local standard time, as filed.
Several spotters reported snowfall meeting warning criteria. Chain restrictions were also required on some of the main roads.
Several spotters reported snowfall meeting warning criteria. Chain restrictions were also required on some of the main roads.
Several spotters reported snowfall meeting warning criteria. Chain restrictions were also required on some of the main roads.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2011Every state in 2011This day in weather historyWarnings in California, March 2011
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: 283423, 283425, 283427.