Station Name: SAN FRANCISCO BAY A NE SHORE ALCATRAZ ISLAND CA
Data Source: Water Data - usgc.gov

Elevation Above Sea Level: 0 feet

Nearest Address:
Alcatraz Island
San Francisco, CA 94133-1312
San Francisco County

GPS Coordinates: 37.8272222, -122.4216667

Nearby Water Temperatures

Coastal Flood Advisory issued December 29 at 2:38AM PST until January 4 at 2:00PM PST by NWS San Francisco CA

Effective: Mon December 29, 2025, 2:38 AM
Expires: Mon December 29, 2025, 3:00 PM

* WHAT...Up to 1.3 ft of inundation above ground level is possible in low lying areas near shorelines and tidal waterways. * WHERE...Bayshore locations along San Francisco and Monterey Bay. * WHEN...From 5 AM Wednesday to 2 PM PST Sunday. * IMPACTS...Flooding of lots, parks, and roads with only isolated road closures expected. * ADDITIONAL DETAILS...The San Francisco tidal gauge high tide is expected to be 1.02 ft above normal (6.86 ft MLLW) at 7:51 AM Wednesday, 1.21 ft above normal (7.05 ft MLLW) at 8:41 AM Thursday, 1.32 ft above normal (7.16 ft MLLW) at 9:34 AM Friday, 1.29 ft above normal (7.13 ft MLLW) at 10:26 AM Saturday, and 1.08 ft above normal (6.92 ft MLLW) at 11:18 AM Sunday. High tide timing varies up to 90 minutes earlier or later along the Pacific Coast and throughout the San Francisco Bay respectively. There is a chance these higher tides coincide with storm surge during an active weather period, so actual tidal levels may be slightly higher than forecast.

If travel is required, allow extra time as some roads may be closed. Do not drive around barricades or through water of unknown depth. Take the necessary actions to protect flood-prone property.

Cold Weather Advisory issued December 28 at 11:13AM PST until December 29 at 9:00AM PST by NWS San Francisco CA

Effective: Sun December 28, 2025, 11:13 AM
Expires: Mon December 29, 2025, 9:00 AM

* WHAT...Cold conditions with temperatures as low as 34 expected. * WHERE...Interior Central Coast, The Santa Clara Valley and Eastern Hills, The East Bay Hills and Valleys, and North Bay Interior Valleys. * WHEN...From 1 AM to 9 AM PST Monday. * IMPACTS...Cold conditions will be hazardous to sensitive populations such as unhoused individuals. Prolonged exposure to the cold conditions will lead to hypothermia for people, pets, and livestock. Cold conditions may damage or kill sensitive crops, plants, and vegetation if appropriate precautions are not taken.

Ensure portable heaters are working properly and are used correctly to avoid sparking a fire indoors. Do not use generators or grills inside as carbon monoxide poisoning can result. Check with your local, city, or county officials for information on available warming centers. Be sure to dress in layers if outdoors. Make sure that pets and livestock have adequate food, unfrozen water, and warmth. Cover or tend to sensitive crops, plants, and vegetation.

Frost Advisory issued December 28 at 11:11AM PST until December 29 at 9:00AM PST by NWS Sacramento CA

Effective: Sun December 28, 2025, 11:11 AM
Expires: Mon December 29, 2025, 9:00 AM

* WHAT...Temperatures as low as 33 to 36 degrees will result in frost formation. * WHERE...Elevations below 2,000 feet in the Motherlode, Carquinez Strait and Delta, Central and Southern Sacramento Valley, and Northern San Joaquin Valley. * WHEN...From 1 AM to 9 AM PST Monday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered. * ADDITIONAL DETAILS...Frost formation may be inhibited by northerly flow along and west of Interstate 5, or in areas where fog forms early on in the night.

Take steps now to protect tender plants from the cold.

Dense Fog Advisory issued December 28 at 11:31PM PST until December 29 at 11:00AM PST by NWS Sacramento CA

Effective: Sun December 28, 2025, 11:31 PM
Expires: Mon December 29, 2025, 11:00 AM

* WHAT...For the Dense Fog Advisory, visibility one quarter mile or less in dense fog. For the Frost Advisory, temperatures as low as 33 to 36 degrees will result in frost formation. * WHERE...Carquinez Strait and Delta, Northern San Joaquin Valley, and Southern Sacramento Valley. * WHEN...For the Dense Fog Advisory, until 11 AM PST Monday. For the Frost Advisory, until 9 AM PST Monday. * IMPACTS...Low visibility could make driving conditions hazardous. Frost could harm sensitive outdoor vegetation, especially if left uncovered. * ADDITIONAL DETAILS...Frost formation may be inhibited by northerly flow along and west of Interstate 5, or in areas where fog forms early on in the night.

Take steps now to protect tender plants from the cold. If driving, slow down, use your headlights, and leave plenty of distance ahead of you.

Frost Advisory issued December 28 at 11:31PM PST until December 29 at 9:00AM PST by NWS Sacramento CA

Effective: Sun December 28, 2025, 11:31 PM
Expires: Mon December 29, 2025, 11:00 AM

* WHAT...For the Dense Fog Advisory, visibility one quarter mile or less in dense fog. For the Frost Advisory, temperatures as low as 33 to 36 degrees will result in frost formation. * WHERE...Carquinez Strait and Delta, Northern San Joaquin Valley, and Southern Sacramento Valley. * WHEN...For the Dense Fog Advisory, until 11 AM PST Monday. For the Frost Advisory, until 9 AM PST Monday. * IMPACTS...Low visibility could make driving conditions hazardous. Frost could harm sensitive outdoor vegetation, especially if left uncovered. * ADDITIONAL DETAILS...Frost formation may be inhibited by northerly flow along and west of Interstate 5, or in areas where fog forms early on in the night.

Take steps now to protect tender plants from the cold. If driving, slow down, use your headlights, and leave plenty of distance ahead of you.