Upper level ridging combined with a series of troughs led to the tightening of pressure gradients over interior northern California. The first trough slipped down and paralleled the California coast causing the north and east pressure to develop and tighten. This brought gusty winds Sunday night into Monday. A brief reprieve in winds occurred mid-Monday, before a second shortwave further reinforced the offshore flow Monday night into Tuesday. This shortwave trough dug south from eastern Washington toward the central and southern portion of the Sierra Nevada. Strong and damaging winds developed across interior northern California resulting in power outages, downed trees, downed power lines, and several small wildfires. Peak gusts ranged from 30 to 60 mph in the Valley, and generally between 40 and 80 mph for the mountains and foothills. Stronger winds were observed along the Sierra Crest.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 18-JAN-21 22:00:00 to 20-JAN-21 00:00:00 (PST-8)
Magnitude: 70.00 MG
Reported by: Law Enforcement

California Highway Patrol reported downed trees and/or power lines on state route 88 in Amador County, highway 4 in Calaveras County, highway 50 in El Dorado County, state route 48 in Placer County, state route 20 in Placer County, and along 108 north of Twain Heart in Tuolumne County.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 18-JAN-21 22:00:00 to 20-JAN-21 00:00:00 (PST-8)
Magnitude: 70.00 MG
Reported by: Law Enforcement

At 1:24AM California Highway Patrol reported that US Highway 50 closed by Sierra Pines Rd due to a pole which fell over powerlines, with low hanging wires.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 18-JAN-21 22:00:00 to 20-JAN-21 00:00:00 (PST-8)
Magnitude: 70.00 MG
Reported by: Law Enforcement

At 12:44AM law enforcement reported that a tree fell in front of a truck, which then collided with it . The truck was stuck on top and medical assistance was requested. This happened on State Route 88 and Kirkwood Meadows Dr., in Kirkwood, CA.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 18-JAN-21 22:00:00 to 20-JAN-21 00:00:00 (PST-8)
Magnitude: 70.00 MG
Reported by: Law Enforcement

At 1:46AM California Highway Patrol reported a tree down across all lanes of US Highway 50, near Silver Fork Rd off ramp in Kyburz, CA.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 18-JAN-21 22:00:00 to 20-JAN-21 00:00:00 (PST-8)
Magnitude: 119.00 MG
Reported by: Mesonet

Mesonet stations across zone 69 reported peak wind gusts between 40-80 mph. Wind reports up to 90-137 mph were observed across the higher elevations of the Sierra.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 18-JAN-21 22:00:00 to 20-JAN-21 00:00:00 (PST-8)
Magnitude: 70.00 MG
Reported by: Public

Dodge Ridge Ski Resort posted on social media that this wind event caused widespread wind damage and cut the communication line to their property. Pictures posted to social media showed massive large trees down. Estimated time for clean up is based on their posts saying January 19-January 28. No estimated damage costs.

High Wind in MT SHASTA/WESTERN PLUMAS COUNTY, CALIFORNIA
From 18-JAN-21 22:00:00 to 19-JAN-21 19:00:00 (PST-8)
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet stations across zone 69 reported peak wind gusts between 40-65 mph.

High Wind in MT SHASTA/WESTERN PLUMAS COUNTY, CALIFORNIA
From 18-JAN-21 22:00:00 to 19-JAN-21 19:00:00 (PST-8)
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

California Highway Patrol reported downed trees and debris along the state routes 147, 89, and highway 70 in Plumas County amd state route 44 in Shasta County near Lassen National Park.

Strong Wind in NORTHERN SAN JOAQUIN VALLEY, CALIFORNIA
From 18-JAN-21 22:00:00 to 19-JAN-21 19:00:00 (PST-8)
Magnitude: 45.00 MG
Property damage: 5.00K
Reported by: Law Enforcement

The California Highway Patrol reported downed tree branches, downed trees, debris, and a pop-up canopy across Stanislaus and San Joaquin counties. Costs are estimated based on these reports.
The ASOS stations at Modesto and Stockton Airports each reported peak wind gusts of 36 mph. Mesonet stations across Stanislaus and San Joaquin counties reported peak wind gusts between 30 and 45 mph. Locally higher gusts up to 52 mph were observed on the ridges of San Joaquin County.

Strong Wind in CARQUINEZ STRAIT AND DELTA, CALIFORNIA
From 18-JAN-21 04:00:00 to 19-JAN-21 19:00:00 (PST-8)
Magnitude: 39.00 MG
Property damage: 50.00K
Reported by: Newspaper

The local media reported that high winds brought down several trees and power lines across Solano County. The report also included that several vegetation and car fires were started due to wind damage and that 2000 customers were without power from this event. Damage costs are estimated based on this report.
Via mesonets and AWOS, the peak wind gusts across Solano County and the Delta varied between 35 and 50 mph. Locally higher gusts up to 62 mph were observed at elevations above 2000 feet.

Strong Wind in SOUTHERN SACRAMENTO VALLEY, CALIFORNIA
From 18-JAN-21 04:00:00 to 19-JAN-21 19:00:00 (PST-8)
Magnitude: 49.00 MG
Property damage: 30.00K
Reported by: Law Enforcement

Law enforcement reported multiple downed trees and powerlines across Sacramento and Yolo counties. Damage costs are estimated for this report.
Wind reports across the area include: Sacramento International, Sacramento Executive, and Davis airports reporting peak wind gusts of 41, 43, and 37 mph respectively. Additional peak wind gust reports around Sacramento County varied from 30 to 43 mph and around Yolo County they varied from 35 to 59 mph.

Strong Wind in CENTRAL SACRAMENTO VALLEY, CALIFORNIA
From 18-JAN-21 04:00:00 to 19-JAN-21 19:00:00 (PST-8)
Magnitude: 37.00 MG
Property damage: 25.00K
Reported by: Law Enforcement

Law enforcement reported that a tree fell onto vehicle at 5819 Park Ave, Linda, CA. They also reported a closure of 8th Street at Highway 70 in Marysville due to low-lying power lines. Peak wind gusts reports across the area ranged from 35 to 43 mph via local AWOS and mesonet stations. Damage is estimated for this report.