San Francisco Heat Watch

Feeling the heat in your neighborhood?

On Friday 9/2, on the five year anniversary of San Francisco’s most extreme heat event, volunteers are mapping urban heat islands to discover which neighborhoods get hottest during heat waves.

The climate crisis is global. Its impacts are local.



In San Francisco, extreme heat events are increasing in frequency and intensity, with significant, cascading, and compounding impacts on public health. And while all San Franciscans are vulnerable to the health impacts of extreme heat, some neighborhoods and communities may be disproportionately impacted. Urban heat islands are areas that can be up to 20 degrees hotter than nearby neighborhoods.


The Urban Heat Watch is an action to map heat in San Francisco’s neighborhoods to understand how our built environment: our green space and our tree canopy, our pavement and our skyscrapers, can create neighborhood-level heat islands that fuel health impacts.




To keep up with the Summer 2022 campaigns, subscribe to the Heat Beat Newsletter, check out the National Integrated Heat Health Information System website, or follow #UrbanHeatMaps2022 on social media.

Matt WolffSan Francisco Urban Heat Watch