California, 2023Winter Storm and Winter Weather in California, February 4 to 5, 2023
February 4 to 5, 2023 · NWS STO · 2 events in 2 counties and zones
A winter storm in early February brought widespread rain with heavy mountain snow for the northern Sierra, which along with gusty winds brought mountain travel impacts. Thunderstorms produced small hail and locally heavy rain in the northern San Joaquin Valley and Motherlode foothills.
- 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.
A winter storm in early February brought widespread rain with heavy mountain snow for the northern Sierra, which along with gusty winds brought mountain travel impacts. Thunderstorms produced small hail and locally heavy rain in the northern San Joaquin Valley and Motherlode foothills. Rainfall amounts in the Valley generally ranged from a tenth of an inch in the northern San Joaquin Valley to around an inch over the northern Sacramento Valley. In the foothills rainfall totals were around a half inch to two and a half inches.
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 Sacramento, CA wrote its last area forecast discussion before the first event at Feb 3, 2:05 PM PST, 9 hours 55 minutes earlier.
Area forecast discussion, Feb 3, 2:05 PM PST, 9 hours 55 minutes before
Area Forecast Discussion
National Weather Service Sacramento CA
205 PM PST Fri Feb 3 2023
.SYNOPSIS...
Dry weather with patchy morning fog before a stronger system
moves through Saturday night and Sunday bringing gusty winds, rain
and heavy mountain snow. Dry weather returns and continues for
much of next week.
&&
.Discussion...
The main part of the upper level trough and low pressure center is
begining to push into BC this afternoon with a short wave trough
pushing to our east. A few light showers are lingering over
southeast portions of the area. These showers will continue to
diminish as the afternoon goes on. Ridging will be building to our
east tonight into tomorrow and that will bring a break from rain
and snow into Saturday. We will see some clearing this evening but
high clouds will quickly move in overnight ahead of our next
system for later Saturday into Sunday. This does bring some
uncertainty for fog potential tonight but given the light rain
today and some clearing expected we should see some patchy fog
develop from around Marysville south. If we see more clearing
some of the fog could be dense.
Upper level trough and cold front then approach the region
Saturday afternoon into Sunday. This will bring the return of rain
and snow. Precip will move in mainly after 4 pm but some light
activity will be possible before that. Widespread rain and snow is
expected for the evening into the overnight. The cold front will
push south of us by daybreak Sunday with the trough axis digging
down the coast. This is going to keep showers in the forecast
throughout the day Sunday.
Models build in 100-500 j/kg of CAPE by Sunday afternoon mainly
from about Chico south. This is also the same area that should see
better forcing during the afternoon with the trough. A few
isolated thunderstorms will be possible. Soundings are not overly
impressive with most of the better shear above 500 mb. We still
see 0-1 km shear up to 20 knots which might be enough for a funnel
cloud or two but overall the threat looks low. The main concern
with any convection would be brief heavy rain and small hail.
A few showers will linger into Sunday night over the mountains,
otherwise dry conditions set in with upper level ridging
developing on Monday. QPF with this system are looking to be
0.25-0.75" in the Valley, 0.75-2" in the foothills, and 1-3" in
the mountains. Snow levels initially start out 5500 to 6500 feet
late Saturday afternoon and lower to 3500 to 4500 feet on Sunday.
The majority of the snow accumulation will be above 4500 feet but
light snow accumulation is expected down to around 4000 feet
Sunday. 1 to 3 feet of snow is expected above 5000 feet and 3 to
15 inches above 4000 feet.
Quiet and dry weather is expected on Monday.
-CJM
&&
.EXTENDED DISCUSSION (Tuesday THROUGH Friday)...
Overall we will see quiet weather for the extended period.
Ensembles bring in a trough mid-week and are struggling with the
placement. It is favored to stay to our north over the PacNW but
30% or so of the members bring it further south. If we would see
this further south solutions some light mountain showers will be
possible Wednesday. Ridging is then favored for the end of the
week. Highs will be seasonal with chilly overnight lows.
-CJM
&&
.AVIATION...
Lingering light showers possible through this afternoon, tapering
off by the evening hours. Southerly wind gusts up to 25-40 kts
over higher terrain through 00Z Saturday. Local MVFR/IFR
visibilities after 10Z-12Z Saturday with BR/FG across portions of
the Sacramento Valley and northern San Joaquin Valley. A stronger
weather system will bring widespread precipitation after 22z
Saturday.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 4 PM Saturday to 10 PM PST Sunday for
West Slope Northern Sierra Nevada-Western Plumas County/Lassen
Park.
&&
Winter Storm, West Slope Northern Sierra Nevada
- When
- February 4, 12:00 AM PST to February 5, 10:00 PM PST
- Where
- West Slope Northern Sierra Nevada forecast zone
- Reported by
- Department of Highways
Caltrans reported traffic was held off and on through the late afternoon and evening of the 5th due to spin-outs. Ski resorts reported more than a foot of snow through February 4-6, 2023. For storm total snowfall UC Berkeley Central Sierra Snow Lab reported 20.9 inches, Kirkwood Ski Resort reported 17 inches, Sierra-at-Tahoe Ski Resort reported 15 inches, Sugar Bowl Ski Resort reported 21 inches, and 18 inches at Palisades Tahoe. Caltrans reported 11 inches at Kingvale, 11 inches at Eagle Lakes, and 8 inches of Blue Canyon.
Winter Weather, Mt Shasta/Western Plumas County
- When
- February 4, 4:00 AM PST to February 5, 10:00 PM PST
- Where
- Mt Shasta/Western Plumas County forecast zone
- Reported by
- SNOTEL
Lower Lassen Peak weather station reported 10 inches of storm total snow. Shingletown 5.4 ENE CoCoRaHS reported 0.2 inches of snow, and Chester Cocorahs reported 1 inch of snow. Gusty winds were observed with this storm, with 70 mph reported at 2.2 NW Pulga (PG&E), 46 mph reported at Carpenter Ridge RAWS, and 58 mph reported at Camel Peak (PG&E).
- Winter Storm
- A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.
- Winter Weather
- Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.
After NWS Directive 10-1605, the rules offices file Storm Data by.
- Flood and Damaging Winds in California, February 4 to 6, 2023$3,000 · 57 kt wind · 13 events
- Heavy Snow and High Wind in California, February 4 to 6, 2023103 kt wind · 6 events
- Heavy Snow and High Wind in Nevada, February 4 to 6, 202399 kt wind · 4 events
- High Wind and Strong Wind in California, February 4, 202358 kt wind · 4 events
- Winter Storm and Extreme Cold in Alaska, February 4 to 7, 20233 events
- Extreme Cold in Connecticut, February 4, 20232 events
- High Wind in Montana, February 4, 202351 kt wind · 2 events
- Winter Weather in Alaska, February 4 to 5, 20232 events
- Flash Flood in Hawaii, February 4, 20231 event
- Lightning Strike in Hawaii, February 4, 2023$1,000 · 1 event
- Heavy Snow in California, February 4 to 5, 20231 event
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: 1082851, 1083018.