A cold upper low moved through the region in early March bringing widespread showers and isolated thunderstorms to the Greater Bay Area. This system caused roadway flooding, debris flows, lightning, and small hail. Snow was also reported on some of the areas peaks throughout the region as snow levels dropped down to 2,000 ft. A mudslide occurred along the River Fire burn scar in Monterey County sending mud and debris into nearby homes.

Flood in MONTEREY, CALIFORNIA
From 10-MAR-21 04:48:00 to 10-MAR-21 06:50:00 (PST-8)
Location: ALTA VISTA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Mudslide reported on River Road between Chualar and Chualar River Road. Over a foot of mud into several homes. Homes were condemned in January so were not occupied at the time.

Flood in ALAMEDA, CALIFORNIA
From 10-MAR-21 06:32:00 to 10-MAR-21 06:52:00 (PST-8)
Location: PIEDMONT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

This roadway flooding occurred at 3601 Telegraph Ave.

Flood in SANTA CLARA, CALIFORNIA
From 10-MAR-21 08:08:00 to 10-MAR-21 08:38:00 (PST-8)
Location: SAN JOSE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Roadway flooding northbound 280 & 87 due to heavy rain.

Flood in SANTA CLARA, CALIFORNIA
From 10-MAR-21 08:08:00 to 10-MAR-21 08:38:00 (PST-8)
Location: ALUM ROCK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Roadway flooding due to heavy rain at the southbound 280 offramp to Alum Rock offramp.

Hail in SONOMA, CALIFORNIA
From 10-MAR-21 10:00:00 to 10-MAR-21 10:30:00 (PST-8)
Location: SANTA ROSA
Magnitude: 0.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Santa Rosa Fire Department reports multiple vehicle accidents on hwy 101 due to accumulating small hail.

Hail in MARIN, CALIFORNIA
From 10-MAR-21 07:45:00 to 10-MAR-21 08:00:00 (PST-8)
Location: MARIN CITY
Magnitude: 0.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image on social media shows small hail in Marin.

Hail in SANTA CLARA, CALIFORNIA
From 10-MAR-21 12:30:00 to 10-MAR-21 12:45:00 (PST-8)
Location: (SJC)SAN JOSE INTL A
Magnitude: 0.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image on social media showing small hail near the San Jose Airport.

Hail in SAN FRANCISCO, CALIFORNIA
From 10-MAR-21 12:25:00 to 10-MAR-21 12:40:00 (PST-8)
Location: SAN FRANCISCO
Magnitude: 0.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter reported small hail in San Francisco.

Winter Weather in SANTA CRUZ MOUNTAINS, CALIFORNIA
From 10-MAR-21 07:00:00 to 10-MAR-21 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image on social media showing about an inch of snow in the Santa Cruz Mountains at 3000 ft.

Hail in SANTA CRUZ, CALIFORNIA
From 10-MAR-21 07:25:00 to 10-MAR-21 07:40:00 (PST-8)
Location: APTOS
Magnitude: 0.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image on social media shows small hail in Aptos.

Hail in SANTA CRUZ, CALIFORNIA
From 10-MAR-21 06:25:00 to 10-MAR-21 06:40:00 (PST-8)
Location: SCOTTS VLY
Magnitude: 0.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported accumulating hail in Scotts Valley at around 1500 ft.