Flood and Heavy Snow in California, March 20 to 22, 2023

Name: Flood and Heavy Snow in California, March 20 to 22, 2023
Start: 2023-03-20T22:00
End: 2023-03-22T22:00
Location: California

March 20 to 22, 2023 · NWS HNX · 29 events in 17 counties and zones

Where it happened

Every event with a place to put it; 27 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $25,000
Crop damage: None recorded
Events: 29

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 HNX wrote it up.

A strong upper trough moved across the region on March 21 and 22. This system produced strong winds across the West Side Hills, the Sierra Nevada and across the Kern County Mountains and Deserts where several stations measured gusts exceeding 60 mph. In addition, heavy snow fell in the Sierra Nevada where several high elevation SNOTEL stations picked up between 18 and 30 inches of new snow while liquid precipitation totals were generally between 1 and 2 inches. Much of the San Joaquin Valley picked up between a quarter and three quarters of an inch of additional rainfall over an already saturated ground while thunderstorm outflow winds knocked down several trees in and around Fresno during the afternoon of March 21.

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 Hanford, CA wrote its last area forecast discussion before the first event at Mar 20, 12:33 PM PST, 9 hours 27 minutes earlier.

Area forecast discussion, Mar 20, 12:33 PM PST, 9 hours 27 minutes before

Area Forecast Discussion
National Weather Service Hanford CA
133 PM PDT Mon Mar 20 2023

.SYNOPSIS...
Brief calm weather conditions will prevail for the rest of the
afternoon, before the next event begins. This event will start to
come into our CWA tonight, with the majority of the precipitation
falling Tuesday through Tuesday night. The system will be petering
out Wednesday afternoon and will have moved out completely by
Thursday morning. Calm weather will prevail for our area through
to Sunday night, with another system coming in Monday morning.

&&

.DISCUSSION...
The calm weather pattern will prevail until tomorrow morning when
an upper level trough will start to push in another storm system
to our CWA. This will bring rainfall to the San Joaquin Valley and
the Sierra foothills and snow showers to the Sierra Nevada above
5000ft. There will also be a chance for thunderstorms in the
valley tomorrow as the cold front associated with the system
moves past. High winds will impact I-5 pass and the mountains
surrounding it by early tomorrow morning and start to effect the
rest of the CWA by the late morning tomorrow. Thunderstorms will
be most likely Tuesday night.

Probabilities for most of our valley locations show 50-75% chance
of receiving 0.5 inches of rain on Tuesday, with Fresno showing a
85% chance of 0.5 inched of rain. Probabilities for some of our
foothills locations show 30-40% chance of 2 inches of rain or more
on Tuesday, and for some of our mountain locations show 45-70%
chance of more than a foot of snow on Tuesday.

After this system moves out of our area, calm weather will prevail
once again and run through Sunday, before another system will come
through the area on Monday. This system appears lighter than this
upcoming one, however this may change as more time passes and
confidence increases.

&&

.AVIATION...
VFR conditions will prevail for rest of the day. Some areas of
MVFR and IFR conditions are possible over the Sierra Nevada due to
the clouds and showers tonight and tomorrow afternoon.

&&

.AIR QUALITY ISSUES...
ISSUED:  03/19/2023 13:28
EXPIRES: 03/20/2023 23:59
None.

&&

.CERTAINTY...

The level of certainty for days 1 and 2 is medium.
The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.html for additional information
and/or to provide feedback.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from late tonight through Wednesday afternoon
for CAZ318-320-322>331.

&&

public...EW
aviation....EW

weather.gov/hanford

The radar

The San Joaquin Valley radar (KHNX), 75 km away, was scanning. The volume nearest the first event began at 18:57 UTC.

Open the radar archive at this moment

Event by event

17 high wind, 10 heavy snow, 1 thunderstorm wind, 1 flood. Local standard time, as filed.

Heavy Snow, Upper San Joaquin River

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Upper San Joaquin River forecast zone
Reported by: SNOTEL
Coordinates: 36.988, -119.706 (the zone’s center; the record gives no point)

The Chilkoot Meadow SNOTEL (7150 feet) picked up an estimated 18 inches of new snowfall.

Heavy Snow, Upper San Joaquin River

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Upper San Joaquin River forecast zone
Reported by: SNOTEL
Coordinates: 36.988, -119.706 (the zone’s center; the record gives no point)

The Kaiser Point SNOTEL (9131 feet) picked up an estimated 19 inches of new snowfall.

Heavy Snow, Kaiser to Rodgers Ridge

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Kaiser to Rodgers Ridge forecast zone
Reported by: SNOTEL
Coordinates: 36.758, -119.649 (the zone’s center; the record gives no point)

The Upper Burnt Corral SNOTEL (9700 feet) picked up an estimated 23 inches of new snowfall.

Heavy Snow, Kings Canyon Np

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Kings Canyon Np forecast zone
Reported by: SNOTEL
Coordinates: 36.489, -119.224 (the zone’s center; the record gives no point)

The Mitchell Meadow SNOTEL (9900 feet) picked up an estimated 31 inches of new snowfall.

Heavy Snow, Kings Canyon Np

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Kings Canyon Np forecast zone
Reported by: SNOTEL
Coordinates: 36.489, -119.224 (the zone’s center; the record gives no point)

The Volcanic Knob SNOTEL (10050 feet) picked up an estimated 31 inches of new snowfall.

Heavy Snow, Kings Canyon Np

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Kings Canyon Np forecast zone
Reported by: SNOTEL
Coordinates: 36.489, -119.224 (the zone’s center; the record gives no point)

The State Lakes SNOTEL (10419 feet) picked up an estimated 27 inches of new snowfall.

Heavy Snow, Sequoia Np

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Sequoia Np forecast zone
Reported by: SNOTEL
Coordinates: 36.220, -118.800 (the zone’s center; the record gives no point)

The Chagoopa Plateau SNOTEL (9450 feet) picked up an estimated 23 inches of new snowfall.

Heavy Snow, Sequoia Np

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: Sequoia Np forecast zone
Reported by: SNOTEL
Coordinates: 36.220, -118.800 (the zone’s center; the record gives no point)

The Farewell Gap SNOTEL (9500 feet) picked up an estimated 27 inches of new snowfall.

Heavy Snow, South End of the Upper Sierra

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: South End of the Upper Sierra forecast zone
Reported by: SNOTEL
Coordinates: 35.782, -118.765 (the zone’s center; the record gives no point)

The Casa Vieja Meadows SNOTEL (8300 feet) picked up an estimated 20 inches of new snowfall.

Heavy Snow, South End of the Upper Sierra

When: March 20, 10:00 PM PST to March 22, 10:00 PM PST
Where: South End of the Upper Sierra forecast zone
Reported by: SNOTEL
Coordinates: 35.782, -118.765 (the zone’s center; the record gives no point)

The Wet Meadows SNOTEL (9019 feet) picked up an estimated 23 inches of new snowfall.

High Wind, Tehachapi

When: March 21, 7:00 AM PST
Where: Tehachapi forecast zone
Measured: 56 kt (64 mph) measured gust
Reported by: Utility Company
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Southern California Edison station at Bear Valley Springs measured a peak wind gust of 65 mph.

High Wind, Tehachapi

When: March 21, 7:40 AM PST
Where: Tehachapi forecast zone
Measured: 55 kt (63 mph) measured gust
Reported by: Utility Company
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Southern California Edison station at Pigeon Spring measured a peak wind gust of 63 mph.

High Wind, Tehachapi

When: March 21, 8:00 AM PST
Where: Tehachapi forecast zone
Measured: 56 kt (64 mph) measured gust
Reported by: Utility Company
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Southern California Edison station at Beartrap Road measured a peak wind gust of 64 mph.

High Wind, Grapevine

When: March 21, 8:10 AM PST
Where: Grapevine forecast zone
Measured: 63 kt (72 mph) measured gust
Reported by: Utility Company
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Southern California Edison station at Tejon Overlook measured a peak wind gust of 72 mph.

High Wind, Frazier Mountain Communities

When: March 21, 9:00 AM PST
Where: Frazier Mountain Communities forecast zone
Measured: 60 kt (69 mph) measured gust
Reported by: Utility Company
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Southern California Edison station at Pelato Peak measured a peak wind gust of 69 mph.

High Wind, West Side Mountains South of Highway 198

When: March 21, 9:20 AM PST
Where: West Side Mountains South of Highway 198 forecast zone
Measured: 52 kt (60 mph) measured gust
Reported by: Utility Company
Coordinates: 36.059, -119.398 (the zone’s center; the record gives no point)

The Southern California Edison station at Las Yeguas measured a peak wind gust of 60 mph.

High Wind, Tehachapi

When: March 21, 10:30 AM PST
Where: Tehachapi forecast zone
Measured: 62 kt (71 mph) measured gust
Reported by: Utility Company
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Southern California Edison station at Tejon Hills measured a peak wind gust of 71 mph.

High Wind, Mariposa - Madera Lower Sierra

When: March 21, 10:40 AM PST
Where: Mariposa - Madera Lower Sierra forecast zone
Measured: 70 kt (81 mph) measured gust
Reported by: Utility Company
Coordinates: 37.400, -119.834 (the zone’s center; the record gives no point)

The PG&E station at Penon Blanco measured a peak wind gust of 80 mph.

High Wind, Fresno - Tulare Lower Sierra

When: March 21, 10:50 AM PST
Where: Fresno - Tulare Lower Sierra forecast zone
Measured: 63 kt (72 mph) measured gust
Reported by: Utility Company
Coordinates: 36.489, -119.224 (the zone’s center; the record gives no point)

The PG&E station at Pine Flat Lake Overlook measured a peak wind gust of 72 mph.

Thunderstorm Wind, Fresno

When: March 21, 11:00 AM PST to 2:17 PM PST
Where: Fresno County, 1.11 mi N of Highway City to 2.36 mi N of Calwa
Measured: 40 kt (46 mph) estimated gust
Property damage: $25,000
Reported by: Fire Department/Rescue
Coordinates: 36.836, -119.882

Several reported trees and power lines were downed in Fresno during the early afternoon of March 21.

High Wind, Mariposa - Madera Lower Sierra

When: March 21, 11:30 AM PST
Where: Mariposa - Madera Lower Sierra forecast zone
Measured: 57 kt (66 mph) measured gust
Reported by: Utility Company
Coordinates: 37.400, -119.834 (the zone’s center; the record gives no point)

The PG&E station at Yosemite Pilot Peak measured a peak wind gust of 66 mph.

High Wind, Yosemite Np Outside of the Valley

When: March 21, 12:00 PM PST
Where: Yosemite Np Outside of the Valley forecast zone
Measured: 56 kt (64 mph) measured gust
Reported by: RAWS
Coordinates: 37.609, -119.874 (the zone’s center; the record gives no point)

The Crane Flat RAWS measured a peak wind gust of 65 mph.

High Wind, West Side Mountains North of Highway 198

When: March 21, 12:20 PM PST
Where: West Side Mountains North of Highway 198 forecast zone
Measured: 55 kt (63 mph) measured gust
Reported by: RAWS
Coordinates: 36.975, -120.184 (the zone’s center; the record gives no point)

The Alcalde RAWS measured a peak wind gust of 63 mph.

High Wind, West Side Mountains North of Highway 198

When: March 21, 12:27 PM PST
Where: West Side Mountains North of Highway 198 forecast zone
Measured: 53 kt (61 mph) measured gust
Reported by: RAWS
Coordinates: 36.975, -120.184 (the zone’s center; the record gives no point)

The Panoche Road RAWS measured a peak wind gust of 61 mph.

High Wind, Coalinga - Avenal

When: March 21, 12:50 PM PST
Where: Coalinga - Avenal forecast zone
Measured: 61 kt (70 mph) measured gust
Reported by: RAWS
Coordinates: 36.417, -119.732 (the zone’s center; the record gives no point)

The Kettlemen Hills RAWS measured a peak wind gust of 70 mph.

High Wind, Mojave Desert Slope(S)

When: March 21, 1:25 PM PST
Where: Mojave Desert Slope(S) forecast zone
Measured: 50 kt (58 mph) measured gust
Reported by: RAWS
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Jawbone Station RAWS measured a peak wind gust of 58 mph.

High Wind, Indian Wells Valley

When: March 21, 3:26 PM PST
Where: Indian Wells Valley forecast zone
Measured: 52 kt (60 mph) measured gust
Reported by: RAWS
Coordinates: 35.343, -118.730 (the zone’s center; the record gives no point)

The Laural Mountain RAWS measured a peak wind gust of 60 mph.

High Wind, West Side Mountains North of Highway 198

When: March 21, 4:50 PM PST
Where: West Side Mountains North of Highway 198 forecast zone
Measured: 60 kt (69 mph) measured gust
Reported by: Utility Company
Coordinates: 36.975, -120.184 (the zone’s center; the record gives no point)

The PG&E station at Joaquin Ridge measured a peak wind gust of 69 mph.

Flood, Fresno

When: March 22, 6:22 PM PST to 9:22 PM PST
Where: Fresno County, 7.51 mi SSW of Oro Loma to 7.59 mi SSW of Oro Loma
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 36.776, -120.721

California Highway Patrol reported southbound Interstate 5 was flooded south of Little Panoche Rd.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
High Wind: Sustained non-thunderstorm winds of 40 mph or more for an hour, or gusts of 58 mph or more.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

Every storm in California in 2023 Every state in 2023 This day in weather history Warnings in California, March 2023

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: 1077908, 1077909, 1077910, 1077911, 1077912, 1077913, 1077914, 1077915, 1077917, 1077918, 1077356, 1077358, 1077357, 1077363, 1077366, 1077354, 1077355, 1077360, 1077364, 1077675, 1077361, 1077368, 1077352, 1077353, 1077367, 1077359, 1077362, 1077351, 1077676.