San Francisco Prepares for Severe Storms

October 22, 2021

The National Weather Service is forecasting significant rain Sunday into Monday, with the potential of 3 to 4 inches of rainfall in span of 24 to 36 hours, gusty southerly winds of up to 45mph and 50mph on the coast, and a high surf warning Sunday evening through Tuesday morning.  

Low-lying and historically flood-prone areas in San Francisco will likely flood. Coastal flooding may be possible along shorelines during high tides. City crews are ready to respond to weather impacts including clearing catch basins and removing downed trees. 

Strong winds may blow down limbs, trees and power lines. Power outages are expected. Members of the public are reminded to report flooding or downed tree limbs to 311 and to treat all downed power lines as active and to report them by calling 911.  

Heavy storms may cause localized flooding, power outages and unsafe street conditions. The following information can help people prepare for and stay safe during the storm:

  • Prevent urban flooding – if you are a San Francisco resident or business, you can pick up 10 free sandbags at the Public Works Operations Yard at the corner of Kansas and Marin Streets on Saturday and Sunday between 8:00 a.m. and 2:00 p.m.
  • Avoid non-essential travel during the storm. If you have to be out, stay away from flooded areas and downed power lines.
  • Call 311 to report downed trees or flooding; treat all downed power lines as live wires and call 911 to report them.  
  • If the power goes out, unplug and turn off appliances. Leave one light on to signal when power is restored.
  • Avoid using candles because they are a fire hazard.
  • Have flashlights and extra batteries available.
  • Stay connected by signing up for emergency text and email alerts from AlertSF. Text your zip code to 888-777 or visit to subscribe.
  • For more storm preparedness information, visit 

The City is taking the following actions to prepare for and respond to weather impacts:

The San Francisco Department of Emergency Management:

The San Francisco Department of Emergency Management will be activating the City’s Emergency Operations Center (EOC) on Sunday to support citywide coordination, situational awareness, and resource management. The public is encouraged to register for AlertSF at or by texting their zip code to 888-777. This is the fastest way to be informed of any type of emergency impacting your area.

The San Francisco Public Utilities Commission:

The San Francisco Public Utilities Commission (SFPUC) will be deploying strike teams and heavy equipment to keep catch basins and storm drains clear of debris. SFPUC will deploy flood barriers on 17th and Folsom starting at 10:00 p.m. tonight and will be distributing sandbags to low-lying neighborhoods, including 15th Avenue at Wawona and Rousseau Street and Cayuga Avenue, among other locations. All property owners, renters and business owners are encouraged to take advantage of resources available to prepare for the storm.

San Francisco Public Works:

San Francisco Public Works is preparing for regular flooded areas by checking on and cleaning up catch basins. Public Works crews will clear leaves and debris that surround the catch basins. The Bureau of Urban Forestry will have an arborist crew on standby Sunday to respond to tree emergencies. To prepare for landslides, Public Works geotechnical engineers assessed eight sites in the City that have had a history of soil erosion and/or rock slippage during heavy rains. Public Works will provide San Francisco residents and businesses up to 10 free sandbags leading up to and during severe rainstorms. Sandbags can be retrieved Saturday and Sunday from 8:00 a.m. to 2:00 p.m. at the Public Works Operations Yard at the corner of Kansas and Marin Streets. Proof of address is required. Sandbags also are sold at many local hardware and home improvement stores.

The media is invited to the Public Works’ operations yard at 12:00 p.m. Saturday, October 22 to capture b-roll of the sandbag distribution and the Public Works spokesperson will be available for media interviews at the Operations Yard sandbag distribution site.

Department of Homelessness and Supportive Housing:

The Department of Homelessness and Supportive Housing (HSH) has activated additional support staff to increase weekend wellness checks for unhoused residents and people experiencing homelessness.  The Homeless Outreach Team will distribute emergency blankets, ponchos, socks, and other warm clothes to unhoused residents and will check for medical needs, including signs of hypothermia.  Unhoused residents will be informed of the severity and duration of the storm and encouraged to take shelter at a location within the existing system of care.  All tents at Safe Sleep Sites have been provided platforms and additional tarps to prevent local flooding and exposure.  Additional placements have also been made available at Sanctuary shelter.  In addition, a 100-person capacity temporary shelter will be opened at Moscone Convention Center West for Sunday and Monday nights. This shelter will be available via referral from the street on a first-come, first served basis and will include transportation via shuttle.

San Francisco Municipal Transportation Agency:

The San Francisco Municipal Transportation Agency (SFMTA) follows standard procedures to weatherize its assets. Track, Overhead Lines, Signal and Power Control units will be staffed 24/7 for support and response during the weather events. SFMTA will coordinate with City Departments and external partners to respond to possible drainage and power issues impacting transportation assets. 

Port of San Francisco:

The Port of San Francisco maintenance crews are monitoring flood prone areas and checking pump stations along the Embarcadero. The maritime division is conducting patrol of small harbors and monitoring needs of port tenants in case they need to move around heavy weather and wind.

San Francisco Recreation and Parks Department:

Park Rangers and the urban forestry tree crew are ready to assist members of the public when needed.

San Francisco Department of Public Health:

The San Francisco Department of Public Health (DPH) has mitigation plans in place for COVID-19 testing and vaccination events. DPH will discontinue operations of outdoor testing and vaccination sites starting Sunday afternoon and will reopen them on Monday, pending safe weather conditions.