Forecast Of Extreme Heat Expands To Include SF, Pacific Coastline

Often blanketed in fog during California heat waves, San Francisco will not escape unscorched this time.

The National Weather Service has expanded its heat advisory to include The City as well as the Pacific Coastline.

San Francisco’s downtown and its neighborhoods along the bay could see highs reach into the low 90s Tuesday, before cooling slightly Wednesday but then climbing again Thursday.

Early Tuesday, the service expanded its heat advisory to include the entire Pacific Coastline stretching from Sonoma County to Big Sur through 8 p.m. Tuesday. Along the coast on the peninsula, temperatures are expected in the upper 70s, in the mid 90s in Santa Cruz and in the 80s down the coast in Monterey County.

Among the hottest will be in Big Sur, which could reach 102 degrees Tuesday and maintain highs in the 90s through the end of the week.

The service considers these conditions a moderate risk for heat-related illness and the warning encompasses a wide geographic area, including the coastal mountains of Marin County, north Monterey Bay, the northern Salinas Valley, Hollister Valley and Carmel Valley. Highs in these additional areas will range upper 80s to low 100s with lows only falling into the 60s and 70s through Thursday.

What is normal is that the inland areas will see the hottest temperatures — approaching 120 degrees in Walnut Creek on Tuesday — which the service considers an extreme risk for heat-related illness Tuesday and Thursday. Wednesday’s slightly cooler conditions are considered a major extreme risk.

The areas affected by the most severe temperatures include the interior areas of the North Bay and East Bay, Santa Clara Valley, Santa Cruz Mountains, interior Monterey County, southern Salinas Valley and San Benito County.

Overnight lows will likely only drop into the mid to upper 60s in interior valleys, with 70s and 80s in the hills.