A powerful winter storm brought heavy rain, heavy snow and strong winds to Southwestern California. Rainfall totals ranged from 2 to 5 inches across coastal and valleys areas with 4 to 10 inches across the foothills and mountains.
Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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 powerful winter storm brought heavy rain, heavy snow and strong winds to Southwestern California. Rainfall totals ranged from 2 to 5 inches across coastal and valleys areas with 4 to 10 inches across the foothills and mountains. Snow levels dropped down, resulting in significant snowfall across the mountains. Below 5000 feet, 6 to 12 inches of snow was reported while the resort level (greater than 6000 feet) received 2 to 5 feet of snowfall. With the snowfall and strong winds, a Blizzard Warning was issues for the mountains of Ventura and Los Angeles counties. As for winds, peak gusts of 60 to 80 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 Feb 21, 10:06 PM PST, 4 hours 54 minutes earlier.
Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1006 PM PST Tue Feb 21 2023
.SYNOPSIS...21/856 PM.
A strong cold front will move over southwest California through
Wednesday morning, with very windy conditions and rapidly falling
snow levels. Cold, showery weather will persist until an unusual
winter storm brings periods of heavy rain and heavy mountain snow
to the region Friday through Saturday night. Improving conditions
are anticipated by Sunday.
&&
.SHORT TERM (TUE-FRI)...21/856 PM.
***UPDATE***
West to northwest winds are ramping up quickly across the area
this evening, with gusts between 60 to 70 mph noted in many
locations, including the Santa Ynez Range and the San Gabriel
Mountains. Some coastal locations are seeing gusts between 55 to
65 mph, highest across the Ventura Coastal Plain, and expected to
spread across the Malibu coastal strip and Santa Monica Mountains,
and the south coast areas of LA County. A High Wind Warning was
issued for these areas, and a wind advisory added for the
interior coastal section of the LA Basin. Expect the warning level
gusts to diminish after around 6 to 7 AM Wednesday, with Advisory
level speeds likely to persist through the mid-morning hours -
through 6 AM for areas north of Point Conception, and through 10
AM further south.
These strong winds are the result of a very cold low pressure
system dropping down the coast overnight, from just south of Point
Conception late this afternoon, far Southern California by 10 PM.
Precipitation amounts will be fairly light tonight through
Wednesday night, but with very low snow levels, expect to see light
snow accumulations in some of the interior valleys and foothills,
with higher amounts in the mountains. This could potentially
include several inches of snow on the Grapevine. In addition,
other lower elevation passes such as San Marcos Pass, Highway 46
in the Santa Lucias, and the Cuesta Grade could see between a
dusting to 1 to 3 inches of snow.
***From Previous Discussion***
A very complex storm event is on our doorstep with many significant
impacts expected in the next few days, some not experienced in
decades. A very cold low pressure trough and surface front are
dropping southward down the Central Coast this afternoon. There
will be the potential for tree damage and power outages just due
to winds alone through Wednesday, along with travel impacts at our
major airports. Snow levels drop rapidly from the current 6k feet
range to near 1k feet tomorrow. Precipitation will not be too
organized through Wednesday night, however, northwest upslope flow
will bring the risk of several inches of snow to the mountains
with impacts on I-5 near the Grapevine. Other foothill areas and
elevated valley floors may also see light snow at times on
Wednesday. Due to this risk, will issue a winter weather advisory
for the Cuyama and Antelope Valleys with amounts of 3-6 inches on
nearby foothills and less than 3 inches for valley floors. Some
uncommon areas of the LA foothill communities, Santa Clarita
Valley, and Santa Ynez foothill communities could experience a
dusting of snow at times through Wednesday night. Thursday will
remain very cool with snow levels remaining near 2500 ft, so
continued scattered rain and snow showers will occur. Temperatures
will be stuck in the 50s for highs in most valleys and coasts
through the next 2-3 days.
The next big impact will be a closed low pressure system that
evolves off the Oregon coast on Thursday, and then dives
southward along our coast to the Channel Islands late Saturday.
Deterministic model data have waffled on the over land vs over
water trajectory since last week, but have now matched the
ensembles with a slow moving system staying over the ocean and
increasing the south wind component for our local terrain.
Precipitation will ramp up due to strong orographic flow with
enhanced rain and snow amounts expected late Thursday night
through early Saturday. Snow levels will fluctuate quite a bit as
the southerly flow will raise levels to about 4500 ft briefly on
Friday afternoon. This could create a mixture of rain/snow at the
I-5 Grapevine area before precipitation turns back to all snow
Friday evening. Rainfall rates will range from 0.50-1.0" per hour
near the main frontal band on Friday bringing a threat of urban
flooding and issues near recent burn scars.
The precipitation totals for the majority of the south Santa
Barbara coast, Ventura, and Los Angeles coasts/valleys will be in
the 2-4 inch category. Low snow levels will mean that this could
be the largest amount of 24-48 hour snowfall seen in decades for
our Ventura and Los Angeles County mountains. Depending on the
snow-line, rainfall in the foothills will be from 4-6 inches, but
the mountains above 4000 ft could see upwards of 2-5 FEET of snow
with isolated amounts to 7 feet at higher elevations. Snowfall of
this rate and amount could lead to damage to structures and trees
with an immense threat of avalanches, especially in the eastern
San Gabriel Mountains by Saturday.
.LONG TERM (SAT-TUE)...21/136 PM.
Saturday will be the last day of precipitation in the forecast
period and could be quite interesting as the closed low moves
directly overhead. The cold, unstable air will be conducive to
development of heavy showers, lightning, and small hail or
graupel. Cyclonic spin would allow for waterspout activity over
the ocean with brief small tornadoes near the coast. Precipitation
coverage would not be as widespread, but most areas are likely to
see additional showers through the day Saturday and snow levels
will remain below 3000 ft.
Sunday could be about the only break in the wet conditions as
there is yet another storm system on the horizon possibly as soon
as Monday or Tuesday next week. ECMWF ensemble data supports a
significant trough along the West Coast near Tuesday-Wednesday
which also shows widespread precipitation amounts. Given the
minimal recovery of upper level heights, snow levels are likely to
be on the lower side once again when this system moves into the
region next week.
&&
.AVIATION...22/0602Z.
At 0516Z at KLAX, there was no marine layer nor inversion.
Low confidence in TAFs. There is a 10-20 percent chance of -shra
over the Ventura County sites Wednesday. High confidence that strong
winds will occur, but lower confidence in wind speeds and timing
of wind changes. Wind gusts could be off by 10 knots. LLWS and
UDDFS are likely over the higher terrain. Cigs may bounce between
flight cats or scatter out and reform through the period.
KLAX...Moderate confidence in TAF. Wind gust speed could be 10
knots higher than forecast and wind changes could be off by 2-3
hours. Good confidence in no significant easterly wind component.
KBUR...Moderate confidence in TAF. Wind gust speed could be off
by 10-15 knots. LLWS and moderate turbulence on descent and climb
possible.
&&
.MARINE...21/917 PM.
Overall, moderate confidence in the current forecast. High
confidence in widespread GALE FORCE winds and very large seas
across the entire coastal waters through Wednesday afternoon.
Moderate confidence exists in STORM FORCE (gusts 48+ knots) winds
through late tonight. The highest chances for GALES will across
the entire coastal waters between 10 pm and 4 am tonight. There is
a 50-70 percent chance of STORM FORCE winds, highest for the
waters from near Point Sal to the south and into the southern
California Bight.
There is a moderate (30-50 percent) chance of winds dropping below
GALE FORCE by late Wednesday morning, then there is a moderate-
to-high (30-60 percent) chance Small Craft Advisory (SCA)
conditions (winds and/or seas) between Wednesday night and early
Friday across the entire coastal waters. Winds will shift south to
southwesterly late Thursday into Friday evening, bringing back a
40-60% chance of brief GALE FORCE gusts to the waters north of
Point Conception, and late Friday morning into evening for the
waters South of Point Conception. Winds and seas will likely
diminish and subside respectively below SCA levels on Saturday.
Dangerous sea conditions are expected through Wednesday as very
large and steep seas build across the entire coastal waters,
peaking near 18 to 22 feet in the very nearshore coastal waters.
Waves this large and steep could be capable of capsizing vessels
or breaking vessels off of anchors or moorings. Breaking waves may
also be possible at Ventura and Morro Bay Harbor entrances.
&&
.BEACHES...21/837 PM.
Strong winds and large seas will bring a high-to-very likely
(50-90 percent) chance of high surf at west and northwest facing
shores by late this evening. Then, increasing to a likely-to-
imminent (70-100 percent) chance by daybreak Wednesday. There is
low-to-moderate (30-50 percent) chance of a HIGH SURF WARNING
being needed between late tonight and Wednesday, highest at
Central Coast beaches.
Frequent steep and chaotic breaking waves along with very strong
winds will create life threatening conditions, even for
experienced ocean swimmers. High surf along with strong rip
currents may continue into Thursday or Friday.
Minor Coastal flooding is possible due to the combination of high
tides and large swells tonight and Wednesday morning. High tides
will be 5.2-5.8 feet occuring between 1000 and 1100 PM tonight
and between 1000 and 1100 AM Wednesday morning.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Winter Storm Warning in effect until 4 AM PST Friday for
zones 53-54. (See LAXWSWLOX).
Blizzard Warning in effect from 4 AM Friday to 4 PM PST
Saturday for zones 53-54-353. (See LAXWSWLOX).
High Wind Warning in effect until 6 AM PST Wednesday for
zones 59-87-349-351-354-362>364-549-550. (See LAXNPWLOX).
Winter Weather Advisory in effect from 4 AM Wednesday to 4 AM
PST Friday for zone 59. (See LAXWSWLOX).
Wind Advisory in effect until 10 AM PST Wednesday for zones
88-350-352-355>359-365-547. (See LAXNPWLOX).
High Surf Advisory in effect until 3 AM PST Friday for zones
340-346. (See LAXCFWLOX).
Wind Advisory in effect until 6 AM PST Wednesday for zones
340>348-353. (See LAXNPWLOX).
Winter Weather Advisory in effect until 1 PM PST Thursday for
zones 342-351-352. (See LAXWSWLOX).
Winter Weather Advisory in effect from 10 AM Wednesday to 1
PM PST Thursday for zone 344. (See LAXWSWLOX).
Winter Storm Warning in effect from 4 AM Wednesday to 4 PM
PST Saturday for zone 345. (See LAXWSWLOX).
High Surf Advisory in effect until 3 AM PST Thursday for
zones 349-350-354-362-364. (See LAXCFWLOX).
Winter Storm Warning in effect from 4 AM Wednesday to 4 AM
PST Friday for zone 353. (See LAXWSWLOX).
PZ...Gale Warning in effect until 3 PM PST Wednesday for zone 645. (See LAXMWWLOX).
Gale Warning in effect until 9 AM PST Wednesday for zone 670. (See LAXMWWLOX).
&&
PUBLIC...EB/Smith
AVIATION...Lund/Rorke
MARINE...Sweet/Lund
BEACHES...Sweet/Hall
SYNOPSIS...EB/Smith
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=loxPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1143 PM PST TUE FEB 21 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1045 PM NON-TSTM WND DMG 4 ENE TORRANCE 33.86N 118.29W
02/21/2023 LOS ANGELES CA LAW ENFORCEMENT
TREE DOWN ON INTERSTATE 110 OFFRAMP.
&&
HALLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1145 PM PST TUE FEB 21 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1141 PM NON-TSTM WND DMG 1 ENE GOLETA 34.44N 119.82W
02/21/2023 SANTA BARBARA CA LAW ENFORCEMENT
TREE DOWN ON HIGHWAY 101 NEAR PATTERSON AVE.
&&
HALLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1204 AM PST WED FEB 22 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1110 PM NON-TSTM WND GST 21 SW GAVIOTA 34.27N 120.48W
02/21/2023 M56 MPH PZZ673 CA MESONET
STORM FORCE WINDS OBSERVED AT BUOY 46054.
&&
HALLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
125 AM PST WED FEB 22 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0953 PM HIGH SUST WINDS 2 WNW HAWTHORNE 33.93N 118.38W
02/21/2023 M41 MPH LOS ANGELES CA ASOS
ASOS STATION KLAX L.A. INTL APT.
1030 PM HIGH SUST WINDS 4 E SAN PEDRO 33.75N 118.27W
02/21/2023 M41 MPH LOS ANGELES CA MESONET
MESONET STATION PFXC1 PORT OF LA, PIER F.
1100 PM NON-TSTM WND DMG 2 SW TORRANCE 33.82N 118.36W
02/21/2023 LOS ANGELES CA BROADCAST MEDIA
POWER LINES DOWN NEAR CALLE MAYOR AND CARLOW
RD.
1100 PM NON-TSTM WND DMG 2 S TORRANCE 33.81N 118.34W
02/21/2023 LOS ANGELES CA BROADCAST MEDIA
POWER LINES DOWN NEAR THE INTERSECTION OF
LOMITA BLVD AND GARNIER ST.
1100 PM NON-TSTM WND DMG TORRANCE 33.83N 118.34W
02/21/2023 LOS ANGELES CA BROADCAST MEDIA
TREE DOWN NEAR THE INTERSECTION OF CARSON ST
AND MERRILL DR.
1100 PM NON-TSTM WND DMG 2 SSW TORRANCE 33.81N 118.35W
02/21/2023 LOS ANGELES CA BROADCAST MEDIA
TREE DOWN ON 23800 BLOCK OF HAWTHORNE BLVD.
&&
HALLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
221 AM PST WED FEB 22 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0522 PM NON-TSTM WND DMG 2 NNW SAN LUIS OBISPO 35.30N 120.67W
02/21/2023 SAN LUIS OBISPO CA LAW ENFORCEMENT
LARGE TREE DOWN ON 200 BLOCK OF N CHORRO ST.
&&
HALLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
227 AM PST WED FEB 22 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0855 PM NON-TSTM WND DMG 3 ESE VENTURA 34.25N 119.21W
02/21/2023 VENTURA CA PUBLIC
LARGE TREE DOWN NEAR HIGHWAY 101 AND
VICTORIA AVE.
&&
HALLThe Vandenberg AFB radar (KVBX), 61 km away, was scanning. The volume nearest the first event began at 19:29 UTC.
9 flash flood, 6 high wind, 4 winter storm, 3 blizzard, 1 tornado. Local standard time, as filed.
Winter storm conditions developed across the mountains of Los Angeles county. Snowfall totals of 6-12 inches with southerly wind gusts, up to 55 MPH, were reported above 5000 feet.
Winter storm conditions developed across the mountains of Ventura county. Snowfall totals of 6-12 inches with southerly wind gusts, up to 55 MPH, were reported above 5000 feet.
Winter storm conditions developed across the mountains of San Luis Obispo county. Snowfall totals of 1-2 feet were reported above 3500 feet with southerly wind gusts up to 50 MPH.
Winter storm conditions developed across the interior mountains of Santa Barbara county. Snowfall totals of 1-2 feet were reported above 3500 feet with southerly wind gusts up to 50 MPH.
Multiple reports of tree damage, associated with a non-supercell tornado, south of East Whitter. The tornado was very small and no injuries were reported.
Rare blizzard conditions developed in the mountains of Santa Barbara county. Heavy snowfall was reported with totals between 1 and 3 feet reported above 4500 feet. Along with the heavy snowfall, strong southerly winds, gusting up to 65 MPH, produced dangerous winter weather conditions with visibilities of near zero miles.
Strong southerly winds impacted the Santa Lucia Mountains in San Luis Obispo county. |Some peak wind gusts from the local mesonet include: TV Towers (gust 64 MPH), Whale Rock (gust 61 MPH) and High School Hill (gust 61 MPH).
Rare blizzard conditions developed in the mountains of Los Angeles county. Heavy snowfall was reported with totals between 3 and 6 feet reported above 5000 feet. Along with the heavy snowfall, strong southerly winds produced dangerous winter weather conditions with visibilities of near zero miles. Some peak wind gusts from the area include: Magic Mountain Truck Trail (gust 86 MPH), Camp Nine (gust 87 MPH), Ford Observatory (gust 73 MPH), and Mill Creek RAWS (gust 65 MPH).
Rare blizzard conditions developed in the mountains of Ventura county. Heavy snowfall was reported with totals between 2 and 4 feet reported above 5000 feet. Along with the heavy snowfall, strong southerly winds produced dangerous winter weather conditions with visibilities of near zero miles. Some peak gusts from the area include: San Guillermo (gust 87 MPH) and Rose Valley (gust 64 MPH).
Strong southerly winds impacted the mountains of San Luis Obispo county. Some peak wind gusts from the local mesonet include: Mount Lowe (gust 64 MPH) and Branch Mountain (gust 58 MPH).
Strong southerly winds impacted the Santa Monica Mountains. Some peak wind gusts from the local mesonet include: Sandstone Peak (gust 93 MPH), Saddle Peak (gust 76 MPH), Topanga RAWS (gust 66 MPH) and Backbone Trail (59 MPH).
Heavy rainfall produced flash flooding on Interstate 5 near Lankershim Boulevard near Burbank. A couple of vehicles were stuck in the flooded roadway.
Strong southerly winds impacted the San Fernando Valley in Los Angeles county. Some peak wind gusts from the local mesonet include: Pacoima (gust 60 MPH) and Ridgebrook Drive (gust 60 MPH).
Strong southerly winds impacted the southeastern valleys of Ventura county. Some peak wind gusts from the local mesonet include: North Ranch (gust 70 MPH), Las Posas Hill (gust 69 MPH) and Miller Ranch (gust 60 MPH).
Heavy rainfall produced flash flooding on Highway 150 at the intersection of Santa Ana Road near Lake Casitas. A couple of vehicles were stuck in the flood waters.
Strong southerly winds impacted the Santa Clarita Valley in Los Angeles county. Some peak wind gusts from the local mesonet include: Newhall Pass (gust 63 MPH), Saugus (gust 63 MPH) and Golden Valley (gust 60 MPH).
Heavy rainfall generated flash flooding and significant mud and debris flows near the 19000 block of Placerita Canyon Road. Several vehicles were stuck in mud that was 25 feet deep.
Heavy rainfall generated flash flooding near the 1300 block on Highway 135, near Vandenberg Village. Swift water rescue team had to rescue two people who drove their vehicles around barricades and into the flooded roadway.
Heavy rainfall generated flash flooding on Ladera Canyon Road near the community of Ojai. Swift water rescue team had to rescue a couple people trapped in a vehicle, due to the flood waters.
Heavy rainfall generated flash flooding on Highway 101 near Campo de Cahuenga. All lanes of the 101 experienced significant flooding.
Heavy rainfall generated flash flooding on Highway 134 near Buena Vista Drive.
Heavy rainfall produced flooding as well as mud and debris flows on Interstate 405 near Rinaldi Drive in the San Fernando Valley.
Heavy rainfall generated flash flooding and significant mud and debris flows across Soledad Canyon Road near Aqua Dulce Road.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2023Every state in 2023This day in weather historyThe tornado archive for California, 2023Warnings in California, February 2023
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: 1084338, 1084339, 1084341, 1084343, 1084329, 1084336, 1084347, 1084334, 1084335, 1084349, 1084346, 1084301, 1084353, 1084350, 1084302, 1084351, 1084322, 1084319, 1084327, 1084324, 1084328, 1084316, 1084320.