A strong ridge of high pressure encompassed the Western CONUS from September 1st through 8th, leading to anomalously hot temperatures along the California coast, and even more extreme temperatures in interior valleys and all mountain zones, where very hot daytime temperatures combined with a lack of overnight cooling created extreme heat risk . Excessive Heat Warnings were issued for interior areas and mountains of Monterey/San Benito Counties for the period September 1st through 8th, and for interior valleys and mountain zones around the San Francisco Bay Area from September 4th through 8th. A combination of Heat Advisories and an Excessive Heat Warning was issued for parts of Monterey Bay and its near coastal valleys, the San Francisco Bay Shoreline, and Marin Coastal Mountains from September 4th through 8th, along with a Heat Advisory for the Central Coast, San Francisco, and coastal North Bay on September 6th. Several daily record high temperature records were shattered, along with a handful of monthly and all-time records. Triple digit temperatures were reported across a vast swath of the interior, with some sites reaching 110 degrees and higher. Reports of power outages, heat related illnesses and deaths were received. Counties opened/operated one or more cooling centers to provide relief from the heat.

Heat in MOUNTAINS OF SAN BENITO COUNTY AND INTERIOR MONTEREY COUNTY INCLUDING PINNACLES NATIONAL PARK, CALIFORNIA
From 04-SEP-22 14:00:00 to 04-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Pinnacles NP reported a max temperature of 111 degrees. Several other unofficial sites in the surrounding mountains reported high temperatures between 102 and 108 degrees.

Heat in SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST, CALIFORNIA
From 04-SEP-22 14:00:00 to 04-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Arroyo Seco RAWS reported a max temperature of 111 deg. Various other unofficial sites in the surrounding mountains reported temperatures between 101 and 108 deg.

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 04-SEP-22 09:00:00 to 08-SEP-22 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Public libraries were used as cooling shelters throughout the county. Cost of operating libraries beyond normal business hours was $1732.04.

Heat in EAST BAY INTERIOR VALLEYS, CALIFORNIA
From 08-SEP-22 14:00:00 to 08-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Livermore set a daily record high temperature of 113 deg, beating its previous record 110 deg set in 1944.

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 04-SEP-22 14:00:00 to 04-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A daily record high temperature of 107 deg was set at the Gilroy Coop site, breaking the previous record 103 deg set in 1998. Various other stations reported temperatures in the upper 90s to mid 100s throughout the valley.

Heat in SAN FRANCISCO BAY SHORELINE, CALIFORNIA
From 05-SEP-22 14:00:00 to 05-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

SFO ASOS set a new daily max temperature record of 97 deg., breaking the previous record of 93 deg., set in 2004. Downtown Oakland Coop site set a new daily max temperature record of 100 deg., breaking the previous record of 95 deg. set in 2008. Redwood City Coop site set a new daily max temperature record of 107 deg., breaking the previous record of 97 deg., set in 1983.

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 04-SEP-22 12:00:00 to 09-SEP-22 20:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Santa Clara County EMS reported 60 calls were received for heat-related illness.

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 05-SEP-22 14:00:00 to 05-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Gilroy Coop site equaled its monthly record max temperature of 112 deg., set in 2017. It also set a new daily record, breaking the previous record of 106 deg., set in 2020. SJC Airport set a new daily max temperature record of 104 deg., breaking the previous record of 99 deg. set in 2008.

Heat in NORTHERN SALINAS VALLEY / HOLLISTER VALLEY / CARMEL VALLEY, CALIFORNIA
From 05-SEP-22 14:00:00 to 05-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Salinas Airport set a new daily max temperature of 103 deg., breaking the previous record of 92 deg., set in 2004.

Heat in NORTHERN SALINAS VALLEY / HOLLISTER VALLEY / CARMEL VALLEY, CALIFORNIA
From 04-SEP-22 14:00:00 to 04-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Hollister ASOS reported a max temperature of 106 deg. Carmel Valley coop site reported a max temperature 101 deg. Other unofficial sites in the vicinity reported max temperatures in the upper 90s to 104 deg.

Heat in EAST BAY INTERIOR VALLEYS, CALIFORNIA
From 05-SEP-22 14:00:00 to 05-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Livermore Coop site set an all time record of 116 deg., breaking the previous all time record of 115 deg. set in 1950. Livermore ASOS reported a max temperature of 113 degrees.

Heat in SAN FRANCISCO BAY SHORELINE, CALIFORNIA
From 04-SEP-22 09:00:00 to 10-SEP-22 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Forty cooling centers opened in Alameda County Bay Shoreline communities.

Heat in EAST BAY INTERIOR VALLEYS, CALIFORNIA
From 04-SEP-22 09:00:00 to 10-SEP-22 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

Six cooling sites opened in Alameda interior valley communities.

Heat in SOUTHERN SALINAS VALLEY / ARROYO SECO / LAKE SAN ANTONIO, CALIFORNIA
From 05-SEP-22 14:00:00 to 05-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

King City Coop site set a new daily max temperature record of 106 deg., breaking the previous record of 105 deg., set in 2020.

Heat in SOUTHERN SALINAS VALLEY / ARROYO SECO / LAKE SAN ANTONIO, CALIFORNIA
From 04-SEP-22 14:00:00 to 04-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

King City coop site tied its daily record of 104 deg set in 1975. Bradley RAWS reported a high temperature of 111 degrees. Various other unofficial sites reported high temperatures between 105 and 111 degrees.

Heat in NORTH BAY INTERIOR VALLEYS, CALIFORNIA
From 05-SEP-22 14:00:00 to 05-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Santa Rosa Coop site set a new monthly max temperature record of 112 deg., breaking the previous record of 110 deg recorded in 2020, 2017, and 1971. Napa Coop site set a new daily max temperature record of 109 deg., breaking the previous record of 102 deg. set in 2020. Kentfield Coop site set a new daily record of 107 deg., breaking the previous record of 103 deg., set in 1950.

Heat in EAST BAY INTERIOR VALLEYS, CALIFORNIA
From 06-SEP-22 14:00:00 to 06-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Livermore tied its all-time record high temperature of 116 deg, which was set the previous day.

Heat in NORTH BAY INTERIOR VALLEYS, CALIFORNIA
From 06-SEP-22 14:00:00 to 06-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Santa Rosa set an all-time record high temperature of 115 deg, beating its previous record 113 deg set in 1913. Downtown Napa set an all-time record high temperature of 114 deg, beating its previous record 113 deg set in 1961.

Heat in SAN FRANCISCO BAY SHORELINE, CALIFORNIA
From 06-SEP-22 14:00:00 to 06-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Redwood City tied its all-time record high temperature of 110 deg set in 1972. It also beat its monthly record 108 deg set in 2020.

Heat in SOUTHERN SALINAS VALLEY / ARROYO SECO / LAKE SAN ANTONIO, CALIFORNIA
From 06-SEP-22 14:00:00 to 06-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

King City reported an all-time record high temperature of 116 deg, beating the previous record 115 deg set in 2017.

Heat in SAN FRANCISCO PENINSULA COAST, CALIFORNIA
From 06-SEP-22 14:00:00 to 06-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Half Moon Bay set a daily record high temperature of 81 deg, beating its previous record 80 deg set in 2004.

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 06-SEP-22 14:00:00 to 06-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

San Jose Airport set an all-time record high temperature of 109 deg, beating the previous record 108 deg set in 2017. Gilroy coop site set a monthly high temperature record of 113 deg, beating the previous record 112 deg set the previous day.

Heat in MOUNTAINS OF SAN BENITO COUNTY AND INTERIOR MONTEREY COUNTY INCLUDING PINNACLES NATIONAL PARK, CALIFORNIA
From 04-SEP-22 10:00:00 to 08-SEP-22 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Two libraries were used as cooling shelters and a third building was opened as a cooling shelter during the event. $300 total was spent by cities and the county to provide bottled water. No fatalities reported.

Heat in NORTH BAY INTERIOR VALLEYS, CALIFORNIA
From 04-SEP-22 12:00:00 to 08-SEP-22 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Four calls received by EMS for heat-related illness. Of those, three were low-priority and one was Code 3 (emergency).

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 08-SEP-22 14:00:00 to 08-SEP-22 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Gilroy set a daily record high temperature of 110 deg, beating its previous record 108 deg set in 1957. San Jose set a daily record high temperature of 104 deg, beating its previous record 100 deg set in 1904.