High pressure aloft centered over Reno, NV along with weak offshore flow at the surface caused temperatures to rise to near 100 degrees in the inland valleys of north-central California. Heat exhausted individuals, blown electric transformers and power outages accompanied the heat.

Heat in SAN FRANCISCO PENINSULA COAST, CALIFORNIA
From 17-MAY-09 11:00:00 to 17-MAY-09 13:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures rose into the upper 80s to mid 90s across the peninsula of the San Francisco Bay Area.

Heat in EAST BAY HILLS AND THE DIABLO RANGE, CALIFORNIA
From 17-MAY-09 12:00:00 to 17-MAY-09 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Temperatures rose into the upper 80s to mid 90s across the mountains of the East San Francisco Bay Area. One hiker was escorted off of Mount Diablo by fire fighter due to heat exhaustion.

Heat in SANTA CRUZ MOUNTAINS, CALIFORNIA
From 17-MAY-09 12:00:00 to 17-MAY-09 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures rose into the 80s to lower 90s across the mountains of Santa Cruz County.

Heat in SANTA CLARA VALLEY INCLUDING SAN JOSE, CALIFORNIA
From 17-MAY-09 10:00:00 to 17-MAY-09 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Temperatures rose into the 90s to just over 100 degrees in the valleys of Santa Clara County. Cooling centers were open across the area to mitigate heat related illnesses.

Heat in SAN FRANCISCO, CALIFORNIA
From 17-MAY-09 12:00:00 to 17-MAY-09 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Temperatures rose into the 80s across San Francisco.

Heat in COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE, CALIFORNIA
From 17-MAY-09 11:00:00 to 17-MAY-09 13:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures rose into the 80s along the coast of the Northern San Francisco Bay Area.

Heat in SAN FRANCISCO BAY SHORELINE, CALIFORNIA
From 17-MAY-09 10:00:00 to 17-MAY-09 19:00:00 (PST-8)
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Newspaper

An overloaded electric transformer failed in Oakland causing more than 5,000 customers to lose power for about three hours.

Heat in EAST BAY INTERIOR VALLEYS, CALIFORNIA
From 17-MAY-09 10:00:00 to 17-MAY-09 19:00:00 (PST-8)
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Newspaper

Several people sought medical attention due to heat-induced fainting spells in Anitoch and Walnut Creek. Also, an electric transformer failed sparking a fire in Walnut Creek near the intersection of Wiget Lane and Ygnacio Valley Road causing 108 customers to lose power. The fire damaged nearby vegetation and an olive tree.

Heat in NORTH BAY INTERIOR VALLEYS, CALIFORNIA
From 17-MAY-09 11:00:00 to 17-MAY-09 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures rose into the mid to upper 90s in the interior valleys of the Northern San Francisco Bay Area.

Heat in NORTH BAY MOUNTAINS, CALIFORNIA
From 17-MAY-09 11:00:00 to 17-MAY-09 15:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures rose into the 80sto lower 90s in the mountains of the Northern San Francisco Bay Area.