INFO PAGE
Extreme heat
San Francisco’s climate is changing. Extreme heat events are becoming more frequent and more intense.
Extreme heat is one of the deadliest weather-related hazards, often causing serious health impacts even at less extreme temperatures due to cumulative heat stress. However, heat-related illnesses and deaths are preventable if you take precautions.
Before a heatwave
- Identify nearby places you can go during heatwaves to stay cool, such as libraries, community centers, swimming pools, or shopping malls.
- Check on neighbors, especially older adults, people with disabilities, and those living alone.
- Know your energy assistance options: PG&E offers energy-saving programs to help reduce cooling costs—visit PG&E's Financial Assistance page.
During a heatwave
- Stay cool by limiting outdoor activities, especially between 10 AM and 4 PM when temperatures are highest. Seek air-conditioned spaces if possible.
- Stay hydrated by drinking plenty of water. Avoid sugary drinks, alcohol, and caffeine.
- Dress for the heat, by wearing lightweight, loose-fitting clothes and a hat.
- Take a cool shower or use wet cloths to lower body temperature
- Cool your space, by keeping blinds or curtains closed during the day and open windows at night if it’s cooler. Use fans with caution, as they do not always prevent heat-related illness. Avoid strenuous activities and heavy meals, which generate body heat.
Heat Wave Map
During extreme heat, stay updated on local conditions with our Heat Wave Map.
This interactive map provides real-time information on cooling center locations, public pools, and water fountains around the city. Check it during heat waves to stay safe and find resources near you.
To explore additional layers, click the drop-down menu in the top-right corner of the map and select “layers” (the icon that looks like a stack of papers).
Recognizing and responding to heat-related illness
Heat exhaustion can progress to heat stroke, a life-threatening emergency. Watch for these warning signs:
- Heavy sweating, weakness, dizziness, headache, or muscle cramps
- Nausea, fainting, or pale skin
- Confusion, hallucinations, or loss of consciousness
- Red, hot, dry skin and a body temperature of 103°F or higher
What to do
- Move to a cool place and drink water immediately.
- If symptoms worsen or if someone is confused, unconscious, or has a fever over 103°F, call 911 right away—this may be heat stroke.
Emergency shelters and cooling centers
- Cooling centers or emergency shelters may be available during extreme heat events, especially for those experiencing homelessness. If you see someone in need of shelter, call 311. If you see someone experiencing a medical emergency, call 911.
Sign up for AlertSF to receive important updates before, during and after emergencies.
Text your ZIP Code to 888-777 or sign up at AlertSF.org.
Learn more
- Find out about how disasters and emergencies can affect San Francisco.
- Review the steps to get prepared for any emergency.
About
Brought to you by the San Francisco Department of Emergency Management (DEM). DEM manages San Francisco's everyday and not-so-everyday emergencies.
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