California, 2012

Winter Storm in California, March 25 to 26, 2012

March 25 to 26, 2012 · NWS LOX · 2 events in 2 counties and zones

A second late-season storm brought another round of rain, wind and snow to Southwestern California. Rainfall totals across the area generally ranged between 1 and 3 inches which resulted in numerous reports of urban flooding.

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
2

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.

What happened

The episode as NWS LOX wrote it up.

A second late-season storm brought another round of rain, wind and snow to Southwestern California. Rainfall totals across the area generally ranged between 1 and 3 inches which resulted in numerous reports of urban flooding. In the mountains, significant snowfall was reported with areas above 5000 feet receiving over 10 inches. The heavy snowfall combined with strong southerly winds to produce dangerous winter weather conditions.

What forecasters said that day

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 Mar 25, 6:30 PM PST, 30 minutes earlier.

Area forecast discussion, Mar 25, 6:30 PM PST, 30 minutes before
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
730 PM PDT SUN MAR 25 2012

.SYNOPSIS...
A COLD SPRING STORM SYSTEM WILL MOVE THROUGH THE AREA THIS AFTERNOON
AND EVENING. PERIODS OF RAIN...MOUNTAIN SNOW...AND A CHANCE OF
THUNDERSTORMS WILL AFFECT THE REGION. FAIR WEATHER WILL RETURN
MONDAY AND TUESDAY WITH OUR NEXT CHANCE OF RAIN ALONG THE CENTRAL
COAST COMING MIDWEEK.

&&

.SHORT TERM (TONIGHT-WED)...DO NOT ANTICIPATE AN UPDATE THIS
EVENING. SURFACE LOW WAS CENTERED 80 MILES WEST OF SAN MIGUEL ISLAND
AND THE NMID/UPPER LEVEL LOW WAS CENTERED OVER THE NORTHERN CHANNEL
ISLANDS THIS EVENING. SURFACE LOW WILL DISSIPATE OVERNIGHT AND THE
REMNANTS WILL MOVE ASHORE WHILE THE MID/UPPER LEVEL LOW SHIFTS EAST
THROUGH EARLY MONDAY MORNING. IN THE MEANTIME RELATIVELY UNSTABLE
SOUNDING AND DEEP MOISTURE WAS OVER THE BIGHT THIS EVENING AND
ISOLATED THUNDERSTORMS WERE MOVING NORTHEAST AT 17 KT. THUNDERSTORMS
WILL LIKELY MOVE ASHORE EARLY THIS EVENING WITH ISOLATED RAIN RATES
BETWEEN .25-.50.

EXCERPT FROM THE FOLLOWING DISCUSSION

SNOW REPORTS THIS AFTERNOON INDICATE SNOW LEVELS AT OR NEAR 5000 FT.
FOCUS OF HEAVIEST RAIN HAS BEEN ALONG THE SANTA MONICA MOUNTAINS IN
THE LAST FEW HOURS WITH SPOTTERS REPORTING SLIGHTLY OVER 2 INCHES IN
THE HILLS BEHIND MALIBU.

UPPER LEVEL LOW QUICKLY EXITS THE REGION TO THE EAST TONIGHT TO BE
FOLLOWED BY A FLAT RIDGE TO START THE WEEK. MONDAY WILL BE A PARTLY
CLOUDY DAY. MAX TEMPS WILL REMAIN BELOW NORMAL.

DRY SOUTHWEST FLOW ALOFT AND WEAK ONSHORE FLOW WILL MAKE FOR A
MOSTLY CLEAR DAY ON TUESDAY WITH A SLIGHT WARMING TREND. STILL MAX
TEMPS WILL REMAIN BELOW NORMAL.

A WEAK FRONT WILL PUSH ACROSS THE CENTRAL COAST ON WEDNESDAY AND
RESULT IN A CHANCE OF LIGHT RAIN NORTH OF PT. CONCEPTION. MAX TEMPS
WILL REMAIN BELOW NORMAL AND WILL ACTUALLY BE A FEW DEGREES BELOW
TUESDAYS NUMBERS.

FLAT ZONAL FLOW FILLS IN OVER THE AREA THURSDAY TO BE FOLLOWED BY A
WEAK RIDGE ON FRIDAY. MOSTLY CLEAR SKIES WILL PREVAIL AND THERE WILL
BE A COUPLE OF DEGREES OF WARMING. A MARINE LAYER CLOUD DECK SHOULD
DEVELOP OVER LA AND VTA COUNTY COASTS AND VALLEYS NIGHTS AND
MORNINGS.

ANOTHER DEEPER TROUGH APPROACHES FOR THE WEEKEND FOR CLOUDS...
COOLING...AND A CHANCE OF PRECIPITATION REGION-WIDE BY SUNDAY.

&&

.AVIATION...26/0000Z.

LOW PRESSURE SYSTEM CENTERED OVER THE AREA WILL CONTINUE TO SHIFT
EAST AND MOVE OVER SOUTHERN NEVADA BY 26/12Z. MID/UPPER LEVEL
MODERATE/STRONG SOUTHWEST WINDS THROUGH 26/06Z THEN  MODERATE/STRONG
NORTHWEST BETWEEN 26/06-26/12Z THEN MODERATE WEST SOUTHWEST AFTER
26/12Z. ISOLATED THUNDERSTORMS THROUGH 26/06Z AND WILL MOVE
NORTHEAST AT APPROXIMATELY 30KT WITH TOPS AROUND 25KFT. STABILITY
WILL INCREASE AFTER 26/06Z.

KLAX...CHANCE THUNDERSTORMS IN THE VICINITY THROUGH 26/05Z.
OTHERWISE SHOWERS WITH CHANCE OF CIGS 025 THROUGH 26/08Z THEN CHANCE
CIGS 040 BETWEEN 26/08-26/11Z.

KBUR...CHANCE THUNDERSTORMS AT TIMES THROUGH 26/03Z. OTHERWISE
SHOWERS WITH CHANCE OF CIGS 025-030 THROUGH 26/16Z.

VIRTUALLY CERTAIN - 95-100%
VERY LIKELY       - 80-95%
LIKELY            - 60-80%
CHANCE            - 30-60%
VERY UNLIKELY     - 20% OR LESS

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING (SEE LAXWSWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&

PUBLIC...TRM
SYNOPSIS...TRM

WWW.WEATHER.GOV/LOSANGELES
Hazardous weather outlook, Mar 25, 1:47 PM PST, 5 hours 13 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
247 PM PDT SUN MAR 25 2012

CAZ034>041-044>046-051>054-059-087-088-547-548-261300-
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-
247 PM PDT SUN MAR 25 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

.DAY ONE... TODAY AND TONIGHT

A WINTER STORM WILL CONTINUE MOVING ACROSS THE AREA THROUGH TONIGHT.
SNOW STORM TOTALS WILL RANGE FROM 8 TO 16 INCHES ABOVE 5500 FEET AND
POSSIBLE LOCAL AMOUNTS UP TO 18 TO 20 INCHES ABOVE 7000 FEET BY
MORNING. SNOW LEVELS MAY POSSIBLY LOWER LOCALLY TO 4000 FEET AND
POSSIBLY AFFECT THE INTERSTATE 5 CORRIDOR THIS EVENING. THERE IS A
SLIGHT CHANCE OF THUNDERSTORMS CAUSING BRIEF PERIODS OF HEAVY RAIN
AND SMALL HAIL. MARINERS SHOULD BE PREPARED FOR A SLIGHT CHANCE OF
THUNDERSTORMS AND ISOLATED WATERSPOUTS ARE POSSIBLE...MAINLY FOR THE
COASTAL WATERS EXTENDING FROM VENTURA HARBOR TO NEWPORT HARBOR.

* WINTER STORM WARNING.......SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

* MARINE WEATHER STATEMENT...SEE FZUS76 KLOX - MWSLOX FOR DETAILS *

* SPECIAL WEATHER STATEMENT..SEE WWUS86 KLOX - SPSLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... MONDAY THROUGH SATURDAY

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.

TRM

In the hours before

Local storm report, Mar 25, 3:50 PM PST, 3 hours 10 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OXNARD CA
450 PM PDT SUN MAR 25 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0200 PM     HIGH SUST WINDS  3 NW LONG BEACH         33.82N 118.19W
03/25/2012  M41.00 MPH       LOS ANGELES        CA   MESONET

            SOUTHEAST WINDS 41 MPH IN THE VICINITY OF LONG
            BEACH...ELEVATION 20 FEET.

0254 PM     NON-TSTM WND GST 6 N ALTADENA            34.27N 118.15W
03/25/2012  M58.00 MPH       LOS ANGELES        CA   OTHER FEDERAL

            SOUTHEAST WINDS 28 MPH GUSTING TO 58 MPH AT CLEAR CREEK
            RAWS...ELEVATION 3000 FEET.

0259 PM     NON-TSTM WND GST 9 SE ACTON              34.39N 118.08W
03/25/2012  M59.00 MPH       LOS ANGELES        CA   OTHER FEDERAL

            SOUTHWEST WINDS 31 MPH GUSTING TO 59 MPH AT MILL CREEK
            RAWS...ELEVATION 5021 FEET.

0259 PM     NON-TSTM WND GST 14 WSW LANCASTER        34.64N 118.41W
03/25/2012  M57.00 MPH       LOS ANGELES        CA   OTHER FEDERAL

            SOUTH WINDS 32 MPH GUSTING TO 57 MPH AT GRASS MOUNTAIN
            RAWS...ELEVATION 4626 FEET.

0353 PM     NON-TSTM WND GST 8 NNE MOUNT WILSON      34.33N 118.03W
03/25/2012  M71.00 MPH       LOS ANGELES        CA   OTHER FEDERAL

            SOUTHEAST WINDS 39 MPH GUSTING TO 71 MPH AT CHILAO
            RAWS...ELEVATION 5450 FEET.

0430 PM     NON-TSTM WND GST 1 WSW MOUNT WILSON      34.22N 118.07W
03/25/2012  M60.00 MPH       LOS ANGELES        CA   OFFICIAL NWS OBS

            SOUTHWEST WINDS 39 MPH GUSTING TO 60 MPH AT MOUNT
            WILSON...ELEVATION 5705 FEET.

&&

HALL

Event by event

2 winter storm. Local standard time, as filed.

Winter Storm, Los Angeles County Mountains Excluding the Santa Monica Range

When
March 25, 7:00 PM PST to March 26, 2:00 AM PST
Where
Los Angeles County Mountains Excluding the Santa Monica Range forecast zone
Reported by
Trained Spotter

A late-season winter storm brought dangerous winter weather conditions to the mountains of Los Angeles county. Above 5000 feet, significant snowfall occurred. Some reports include: Mountain High (14 inches) and Wrightwood (14 inches). The heavy snowfall combined with gusty south winds in excess of 60 MPH to produce dangerous winter storm conditions.

Winter Storm, Ventura County Mountains

When
March 25, 7:00 PM PST to March 26, 2:00 AM PST
Where
Ventura County Mountains forecast zone
Reported by
Trained Spotter

A late-season winter storm brought dangerous winter weather conditions to the mountains of Ventura county. Above 5000 feet, significant snowfall occurred. Some reports include: Mount Pinos (12 inches), Pine Mountain Club (8 inches), and Frazier Park (10 inches). The heavy snowfall combined with gusty south winds in excess of 60 MPH to produce dangerous winter storm conditions.

What these are

Winter Storm
A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in California in 2012Every state in 2012This day in weather historyWarnings in California, March 2012

Sources

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: 368337, 368338.