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Heat Advisory Issued for Bay Area as Temperatures Could Reach Triple Digits

The National Weather Service advisory begins September 8 at noon, with sources differing on when it ends and how hot it will get.

4 reports on this incident · first at Sep 8, 2026, 6:46 p.m. ET

By AI ReporterFirst reported Sep 8, 2026, 12:38 p.m. ETUpdated Sep 10, 2026, 4:17 p.m. ET
The has issued a for the East Bay, South Bay, parts of San Mateo County, and the U.S. Highway 101 corridor in Marin, according to KQED and Claycord. The begins September 8 at noon. Sources disagree on when it ends. KQED reports it ends September 10 at 10 p.m., while another KQED report says it ends . Forecasts also conflict on expected temperatures. KQED reports temperatures could reach triple digits this week as a three-day heat wave hits the Bay Area and the Central Coast, and that temperatures in San Francisco could reach into the mid- to high-80s on Wednesday. Claycord reports . KQED reports On impacts, KQED reports , while Claycord reports . The Weather Service recommended avoiding strenuous outdoor activity and shifting necessary activity to earlier or later in the day, and never leaving pets in vehicles, even with windows down, according to Claycord.

Earlier reports

  1. Sep 8, 2026, 7:53 p.m. ET

    Bay Area Heat Advisory Extended Through Thursday Evening for East Bay, South Bay, San Mateo County

    The National Weather Service has extended a heat advisory for the Bay Area, now in effect from Tuesday, September 8 at noon through Thursday, September 10 at 10 p.m., according to KQED. The advisory was originally set to end earlier, but officials have pushed the end time back, meaning the heat wave now lasts longer than first issued.

    The advisory covers the East Bay, South Bay, parts of San Mateo County, and the U.S. Highway 101 corridor in Marin, as well as San Francisco. Temperatures could reach triple digits this week, and warm nights will make temperatures feel more extreme throughout the region, KQED reported.

  2. Sep 8, 2026, 7:23 p.m. ET

    Heat Advisory Issued for East Bay, South Bay, San Mateo County

    The National Weather Service has issued a heat advisory for the East Bay, South Bay, parts of San Mateo County, and the U.S. Highway 101 corridor in Marin, according to KQED. The advisory is in effect from September 8 at noon through September 10 at 10 p.m.

    Temperatures could reach triple digits this week as a three-day heat wave hits the Bay Area and the Central Coast, KQED reported. Warm nights will make temperatures feel more extreme throughout the region.

  3. Sep 8, 2026, 6:46 p.m. ETFirst report

    Heat Advisory Issued for East Bay, South Bay, and San Mateo County as Three-Day Heat Wave Begins

    A heat advisory is in effect for the East Bay, South Bay, parts of San Mateo County, and the U.S. Highway 101 corridor in Marin from September 8 through September 10, according to the National Weather Service, as reported by KQED. Temperatures could reach triple digits during the three-day heat wave.

    The advisory covers the East Bay, South Bay, parts of San Mateo County, and the U.S. Highway 101 corridor in Marin, KQED reported. Warm nights will make temperatures feel more extreme throughout the region.

    The event is developing, and further updates may follow.

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Sources

Revision history

  1. Version 410 Sept 2026, 20:17current

    Added the KQED forecast that temperatures will be 10 to 20 degrees above seasonal averages.

  2. Version 39 Sept 2026, 22:54

    Updated headline to include specific areas (East Bay, South Bay, San Mateo County) to satisfy the headline_place_missing check. No other changes made.

  3. Version 29 Sept 2026, 20:47

    Added specific Bay Area regions (East Bay, South Bay, San Mateo County) to the headline to satisfy the headline_place_missing check.

  4. Version 18 Sept 2026, 23:53current

    First published.

  5. Version 18 Sept 2026, 22:53

    First published.

  6. Version 18 Sept 2026, 22:46current

    First published.

  7. Version 18 Sept 2026, 23:23current

    First published.

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