A strong upper low pressure system moved through California on December 27. This system had abundant moisture associated with it as it pulled up a deep fetch of moisture of tropical origin. This system brought widespread moderate to heavy precipitation to the area between the early morning until the early evening of December 27. The heavy rainfall produced a rockslide in Yosemite National Park which resulted in two fatalities. The precipitation tapered off by the early morning of December 28. Much of the higher Sierra Nevada picked up between an inch and a half and three inches of liquid precipitation with the precipitation mainly falling as snow above 7500 feet where many stations picked up between 18 and 30 inches of new snowfall. The snow level briefly lowered to around 6000 feet during the evening of December 27 and some light snowfall was observed between 6000 and 7500 feet. The Sierra foothills generally received between 1 to 2 inches of rain while 0.75 to 1.5 inches of rain fell in the San Joaquin Valley and the Tehachapi Mountains. Several reports of nuisance flooding were reported by law enforcement and on social media. Rain shadowing effects limited precipitation in the Kern County Deserts to a quarter inch or less. This system also brought some strong wind gusts to the mountains as several stations measured gusts exceeding 40 mph and a few low impact stations had brief gusts above 60 mph.

High Wind in MARIPOSA - MADERA LOWER SIERRA, CALIFORNIA
From 27-DEC-22 05:30:00 to 27-DEC-22 05:30:00 (PST-8)
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Utility Company

The PG&E station at Yosemite Pilot Peak measured a peak wind gust of 59 mph.

High Wind in MOJAVE DESERT SLOPE(S), CALIFORNIA
From 27-DEC-22 13:32:00 to 27-DEC-22 13:32:00 (PST-8)
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Blue Max RAWS measured a peak wind gust of 61 mph.

High Wind in SOUTH END OF THE UPPER SIERRA, CALIFORNIA
From 27-DEC-22 06:27:00 to 27-DEC-22 06:27:00 (PST-8)
Magnitude: 67.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Bird Springs Pass RAWS measured a peak wind gust of 77 mph.

Flood in KERN, CALIFORNIA
From 27-DEC-22 18:56:00 to 27-DEC-22 20:56:00 (PST-8)
Location: MYRICKS CORNER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported flooding near the intersection of SR 43 and Merced Ave. near Shafter.

Heavy Snow in SEQUOIA NP, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Crabtree Meadow SNOTEL (10700 feet) picked up an estimated 23 inches of new snowfall.

Heavy Snow in SEQUOIA NP, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Upper Tyndall Creek SNOTEL (11443 feet) picked up an estimated 23 inches of new snowfall.

High Wind in SOUTH END OF THE UPPER SIERRA, CALIFORNIA
From 27-DEC-22 07:10:00 to 27-DEC-22 07:10:00 (PST-8)
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Bear Peak RAWS measured a peak wind gust of 70 mph.

High Wind in SOUTH END OF THE UPPER SIERRA, CALIFORNIA
From 27-DEC-22 06:00:00 to 27-DEC-22 06:00:00 (PST-8)
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Walker Pass RAWS measured a peak wind gust of 63 mph.

Heavy Snow in UPPER SAN JOAQUIN RIVER, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Green Mountain SNOTEL (7900 feet) picked up an estimated 26 inches of new snowfall.

Heavy Snow in UPPER SAN JOAQUIN RIVER, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Devil's Postpile SNOTEL (8004 feet) picked up an estimated 24 inches of new snowfall.

Debris Flow in MARIPOSA, CALIFORNIA
From 27-DEC-22 09:00:00 to 27-DEC-22 10:00:00 (PST-8)
Location: FORESTA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Yosemite National Park employees reported two people were killed by a rockslide near the intersection of SR 140 and Big Oak Flat Road in Yosemite National Park.

Flood in TULARE, CALIFORNIA
From 27-DEC-22 14:17:00 to 27-DEC-22 16:17:00 (PST-8)
Location: PAIGE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported roadway flooding at Ave 224 and Ave 216 south of SR 137 west of Tulare.

Flood in FRESNO, CALIFORNIA
From 27-DEC-22 05:34:00 to 27-DEC-22 07:34:00 (PST-8)
Location: BIG CREEK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported rocks on the road blocking east bound lanes of Huntington Lake Road.

Flood in MERCED, CALIFORNIA
From 27-DEC-22 09:33:00 to 27-DEC-22 11:33:00 (PST-8)
Location: SANTA NELLA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported roadway flooding at SR 152 and the Romero Visitor Center.

Heavy Snow in UPPER SAN JOAQUIN RIVER, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Kaiser Point SNOTEL (9131 feet) picked up an estimated 24 inches of new snowfall.

Heavy Snow in KAISER TO RODGERS RIDGE, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The West Woodchuck Meadow SNOTEL (9209 feet) picked up an estimated 23 inches of new snowfall.

Flood in FRESNO, CALIFORNIA
From 27-DEC-22 10:02:00 to 27-DEC-22 12:02:00 (PST-8)
Location: LAKESHORE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported a huge boulder on the roadway on SR 168 4E Huntington Lake.

Flood in FRESNO, CALIFORNIA
From 27-DEC-22 10:52:00 to 27-DEC-22 12:52:00 (PST-8)
Location: MINKLER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported both sides of the roadway flooded at S. Reed Ave. and E. Annadale Ave.

Heavy Snow in KAISER TO RODGERS RIDGE, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Upper Burnt Corral SNOTEL (9700 feet) picked up an estimated 25 inches of new snowfall.

Heavy Snow in KAISER TO RODGERS RIDGE, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Blackcap Basin SNOTEL (10300 feet) picked up an estimated 23 inches of new snowfall.

Flood in KERN, CALIFORNIA
From 27-DEC-22 16:43:00 to 27-DEC-22 18:43:00 (PST-8)
Location: PUMPKIN CENTER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported flooding on southbound SR 99 as well as on the off ramp of southbound SR 99 to SR 119.

Flood in KERN, CALIFORNIA
From 27-DEC-22 17:18:00 to 27-DEC-22 19:18:00 (PST-8)
Location: TUPMAN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported a small mudslide blocking the southbound lane of Tupman Road north of SR 119.

Flood in MARIPOSA, CALIFORNIA
From 27-DEC-22 11:26:00 to 27-DEC-22 13:26:00 (PST-8)
Location: EL PORTAL
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

California Highway Patrol reported SR 140 entrance to Yosemite closed due to a rockfall 3 miles east of the tollbooths.

Heavy Snow in YOSEMITE NP OUTSIDE OF THE VALLEY, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Tenaya Lake SNOTEL (8150 feet) picked up an estimated 18 inches of new snowfall.

Heavy Snow in KINGS CANYON NP, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Volcanic Knob SNOTEL (10050 feet) picked up an estimated 28 inches of new snowfall.

Heavy Snow in KINGS CANYON NP, CALIFORNIA
From 27-DEC-22 04:00:00 to 27-DEC-22 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Charlotte Lake SNOTEL (11961 feet) picked up an estimated 28 inches of new snowfall.

Flood in KERN, CALIFORNIA
From 27-DEC-22 18:13:00 to 27-DEC-22 20:13:00 (PST-8)
Location: ROSEDALE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported flooding on Calloway Dr. underneath the railroad bridge north of Slinker Dr.

Flood in KERN, CALIFORNIA
From 27-DEC-22 18:26:00 to 27-DEC-22 20:26:00 (PST-8)
Location: KERN JCT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported flooding on westbound SR 58 at the intersection of Cottonwood Rd.