A late season winter storm brought snow and very gusty winds to the mountains of Ventura and Los Angeles counties. Many areas reported snowfall amounts between 4 and 8 inches.
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 LOX wrote it up.
A late season winter storm brought snow and very gusty winds to the mountains of Ventura and Los Angeles counties. Many areas reported snowfall amounts between 4 and 8 inches. In addition, southerly wind gusts to 61 MPH were reported.
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 Los Angeles, CA wrote its last area forecast discussion before the first event at Apr 12, 8:20 AM PST, 2 hours 40 minutes earlier.
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 920 AM PDT MON APR 12 2010 .SYNOPSIS... COLD UPPER LEVEL LOW PRESSURE SYSTEM ACROSS CALIFORNIA WILL CONTINUE TO BRING SCATTERED SHOWERS WITH A SLIGHT CHANCE OF THUNDERSTORMS TODAY...ALONG WITH MOUNTAIN SNOW SHOWERS. DRIER CONDITIONS TO PREVAIL THE REMAINDER OF THE WEEK WITH TEMPERATURES REMAINING SLIGHTLY BELOW NORMAL. && .SHORT TERM (TODAY-WED)... COLD UPPER LEVEL LOW PRESSURE SYSTEM CURRENTLY CENTERED ACROSS NORTHERN CALIFORNIA WITH MOIST CYCLONIC FLOW CONTINUING ACROSS CENTRAL AND SOUTHERN CALIFORNIA. MAIN COLD FRONT HAS PUSHED WELL SOUTH AND EAST OF AREA... BUT COLD AND SLIGHTLY UNSTABLE AIR MASS WILL CONTINUE TO BRING SCATTTERED SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS TO THE FORECAST AREA TODAY. AREAS NORTH OF POINT CONCEPTION WILL HAVE THE MOST NUMEROUS SHOWER ACTIVITY...SO HAVE CONTINUED TO KEEP HIGHER POPS FOR THOSE AREAS. CURRENT SATELLITE AND DOPPLER RADAR IMAGERY CONFIRM THIS IDEA. AUTOMATED GAUGES SHOWING RAINFALL RATES LESS THAN .20 INCHES PER HOUR SO FAR...BUT IF ANY THUNDERSTORMS WERE TO DEVELOP TODAY...COULD SEE LOCALLY HIGHER RAINFALL RATES. AS FAR AS CONVECTION IS CONCERNED...MSAS LIFTED INDEX ANALYSIS SHOWING MOST UNSTABLE AIR CURRENTLY LOCATED OFF THE CENTRAL COAST. BUT NAM-12 MODEL SHOWING A BROAD AREA OF 0 TO -1 LIFTED INDICES ACROSS THE REGION DURING THE NEXT 4 HOURS. LOOK FOR ATMOSPHERE TO CONTINUE DESTABILIZING NEXT FEW HOURS DUE TO THE COMBINATION OF DAYTIME HEATING DUE TO BREAKS IN CLOUD COVERAGE...ALONG WITH COLD AIR ALOFT. IN FACT...NAM 12 MODEL HAS 500 MB TEMPERATURES BETWEEN -25 AND -27 DEGREES CELSIUS THROUGH EARLY AFTERNOON. AS THE LAPSE RATES STEEPEN NEXT FEW HOURS...BEST CHANCE OF CONVECTION WILL LIKELY OCCUR BETWEEN 18Z-21Z...SO SLIGHT CHANCE OF THUNDERSTORMS STILL LOOKS GOOD ACROSS REGION. ANY STORMS THAT DO DEVELOP WILL BE CAPABLE OF PRODUCING BRIEF HEAVY DOWNPOURS AND SMALL HAIL. BY LATE AFTERNOON...UPPER TROUGH AXIS SHIFTS EASTWARD...RESULTING IN RISING HEIGHTS AND WARMING TEMPERATURES ALOFT. THIS WILL LIKELY HELP TO STABLIZE THE ATMOSPHERE...RESULTING IN DECREASED SHOWER ACTIVITY BY LATE AFTERNOON INTO EVENING. ANY ADDITIONAL RAINFALL ACCUMULATIONS TODAY SHOULD GENERALLY BE UNDER .25 INCHES...BUT AREAS UNDER A HEAVY SHOWER OR THUNDERSTORM COULD PICK UP A QUICK .50 INCH BURST. SINCE THERE IS NO LONGER ANY ORGANIZED SNOWFALL IN THE MOUNTAINS...WILL DOWNGRADE WINTER STORM WARNING TO A WINTER WEATHER ADVISORY. MOUNTAINS COULD STILL SEE AN ADDITIONAL 1 TO 3 INCHES OF SNOW ACCUMULATION TODAY. SNOW LEVELS WILL REMAIN BETWEEN 4000 AND 5000 FEET THROUGH THE DAY...WITH LOCALLY LOWER SNOW LEVELS UNDER CONVECTION. *** FROM PREVIOUS DISCUSSION *** SHOWER ACTIVITY (WHICH WILL MOSTLY BE OVER THE MTNS AND THE CENTRAL COAST) WILL QUICKLY DIMINISH THIS EVENING...EXCEPT ON THE MOUNTAIN SLOPES NEAR THE KERN COUNTY LINE WHERE UPSLOPE FLOW WILL KEEP CLOUDS AND A SLIGHT CHC OF SHOWERS GOING THROUGH TUESDAY MORNING. FAIRLY DRY WESTERLY FLOW SETS UP TUESDAY. SKIES WILL BE PARTLY CLOUDY. WITH ONLY 566 DM HGTS OVERHEAD MAX TEMPS WILL REMAIN SEVERAL DEGREES BELOW NORMAL. A COLD UPPER LOW WILL SPIN RAIN AND GLOOM INTO OREGON WEDNESDAY. THIS LOW WILL TILT THE FLOW OVER CALIFORNIA TO THE SW. THE FLOW IS FAIRLY DRY AND SKIES WILL BE AT WORST PARTLY CLOUDY. HGTS ACTUALLY RISE A FEW DM AND MAX TEMPS ACROSS THE COASTS AND VLYS WILL BUMP UP INTO THE UPPER 60S AND LOWER 70S. .LONG TERM (THU-SUN)... THE SW FLOW CONTINUE THU AND FRI. THERE IS ENOUGH ONSHORE FLOW TO CREATE A MARINE LAYER OVER THE CENTRAL COAST AND THE L.A. COAST. ON FRIDAY A LITTLE IMPULSE EMBEDDED IN THE SW FLOW RIPPLES THROUGH THE AREA. THE 06Z GFS BRINGS A LITTLE MORE MOISTURE WITH THIS SYSTEM AND WILL HAVE WATCH THE TRENDS WITH THIS SYSTEM. COOLER WITH HGTS DIPPING TO 568 DM. FRIDAY MIGHT BE COOLER STILL IF THAT EXTRA MOISTURE CREATES MOSTLY CLOUDY SKIES. BOTH THE EC AND THE GFS POP UP A LITTLE RIDGE SATURDAY AND RIGHT NOW THIS LOOKS LIKE IT WILL BE THE WARMEST DAY OF THE NEXT 7. THE MDLS HAVE BEEN STRUGGLING WITH THE SUNDAY FORECAST WITH THE GFS ALTERNATING BETWEEN WET AND DRY WITH EACH SUCCESSIVE RUN. EC HAS BEEN CONSISTENTLY DRY AND FOLLOWED ITS LEAD WITH A DRY FCST FOR SUNDAY. && .AVIATION...12/1130Z... MOIST AND UNSTABLE AIR MASS IN THE WAKE OF A COLD FRONTAL PASSAGE WILL PRODUCE A PARTLY TO MOSTLY CLOUDY DAY ACROSS THE TERMINALS. THERE WILL LIKELY BE SOME PERIODS OF MVFR CIGS THROUGH THIS EVENING ALL COASTAL AND VALLEY TAF SITES...MAKING FOR A RATHER LOW CONFIDENCE FORECAST FOR MOST TAF SITES. WILL INDICATE A GENERAL SCT DECK AROUND 025 THROUGH THIS AFTERNOON. IN ADDITION...THERE WILL BE SOME SCATTERED SHOWERS AROUND THE AREA THROUGH THIS EVENING ALONG WITH A SLIGHT CHANCE OF TSTMS. KLAX...LOW TO MODERATE CONFIDENCE IN 12Z TAF. THERE IS A 50% CHANCE OF MVFR CIGS AT THE AIRFIELD THROUGH THIS EVENING. KBUR...LOW TO MODERATE CONFIDENCE IN 12Z TAF. THERE IS A 50% CHANCE THAT THE FORECAST MVFR CIGS MAY DISSIPATE ANYTIME THROUGH THE DAY. ***NOTE*** THE ASOS EQUIPMENT AT KBUR...KVNY...KHHR...KCMA...AND KOXR HAS A SOFTWARE ERROR THAT MAY LEAD TO INCORRECT CLOUD HEIGHTS WHEN THERE ARE TWO OR MORE CLOUD LAYERS PRESENT. OBSERVATIONS AT KBUR WILL BE QUALITY CONTROLLED 24 HOURS A DAY...OBSERVATIONS AT KVNY WILL BE QUALITY CONTROLLED FROM 13Z-07Z...OBSERVATIONS AT KOXR WILL BE QUALITY CONTROLLED FROM 15Z-05Z. TAFS FOR KVNY AND KOXR WILL NOT BE AMENDED FOR CIGS DURING THE TIME THE OBSERVATIONS ARE NOT MONITORED AND THERE ARE TWO OR MORE CLOUD LAYERS PRESENT. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXMWWLOX). WINTER WEATHER ADVISORY (SEE LAXWSWLOX). && PUBLIC...GOMBERG/RORKE AVIATION...THOMPSON SYNOPSIS...ASR WWW.WEATHER.GOV/LOSANGELES
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 600 AM PDT MON APR 12 2010 CAZ034>041-044>046-051>054-059-087-088-547-548-131300- SAN LUIS OBISPO COUNTY CENTRAL COAST- SANTA BARBARA COUNTY CENTRAL COAST-SANTA YNEZ VALLEY- SAN LUIS OBISPO COUNTY INTERIOR VALLEYS-CUYAMA VALLEY- SANTA BARBARA COUNTY SOUTH COAST-VENTURA COUNTY COAST- LOS ANGELES COUNTY COAST INCLUDING DOWNTOWN LOS ANGELES- VENTURA COUNTY INTERIOR VALLEYS-VENTURA COUNTY COASTAL VALLEYS- SANTA MONICA MOUNTAINS RECREATIONAL AREA- SAN LUIS OBISPO COUNTY MOUNTAINS- SANTA BARBARA COUNTY MOUNTAINS-VENTURA COUNTY MOUNTAINS- LOS ANGELES COUNTY MOUNTAINS EXCLUDING THE SANTA MONICA RANGE- ANTELOPE VALLEY-CATALINA ISLAND-SANTA CLARITA VALLEY- LOS ANGELES COUNTY SAN FERNANDO VALLEY- LOS ANGELES COUNTY SAN GABRIEL VALLEY- 600 AM PDT MON APR 12 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA. .DAY ONE... TODAY AN UNSTABLE AIR MASS IN THE WAKE OF A COLD FRONTAL PASSAGE WILL CONTINUE TO GENERATE SCATTERED SHOWERS ACROSS THE AREA THROUGH THIS AFTERNOON. ALONG WITH THE SHOWERS...THERE WILL BE THE SLIGHT CHANCE OF THUNDERSTORMS. IN THE MOUNTAINS OF VENTURA AND LOS ANGELES COUNTIES...DANGEROUS WINTER STORM CONDITIONS WILL PERSIST THROUGH THIS MORNING. SNOW LEVELS WILL REMAIN AROUND 4500 TO 5000 FEET. * WINTER STORM WARNING.......SEE WWUS46 KLOX - WSWLOX FOR DETAILS * .DAYS TWO THROUGH SEVEN... TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. THOMPSON
2 winter storm. Local standard time, as filed.
A powerful late season winter storm brought snow and gusty winds to the mountains of Los Angeles county. Mountain High and Big Pines both reported 6 inches of snowfall. Along with the snowfall, strong southerly winds developed with gusts to 61 MPH reported.
A powerful late season winter storm brought snow and gusty winds to the mountains of Ventura county. Cuddy Valley reported 4 to 8 inches of snowfall. Along with the snowfall, strong southerly winds developed with gusts to 61 MPH reported.
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, April 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: 224432, 224433.