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Updated:July 15, 2026 1:00 pm PDT

Coastal Flood Advisory COASTAL FLOOD ADVISORY  
San Mateo County

  Effective: Wed, 7/15 3:38am Severity: Minor
  Updated: July 15, 2026 1:00 pm Urgency: Expected
  Expires: Thu, 7/16 4:00am Certainty: Likely

Areas Affected: San Francisco - North Bay Interior Valleys - San Francisco Bay Shoreline
 
Alert Details:
* WHAT...Up to 1.5 ft of inundation above ground level is
possible in low-lying areas near shorelines and tidal waterways.

* WHERE...Bayshore locations along the San Francisco and San
Pablo Bays.

* WHEN...Until 4 AM PDT Thursday.

* IMPACTS...Flooding of lots, parks, and roads with only
isolated road closures expected.

* ADDITIONAL DETAILS...At the San Francisco tidal gauge, high tide
is expected to be 1.5 ft above normal (7.3 ft MLLW) at 12:48 AM
7/16. These predictions include both astronomical tides and
roughly 3-6 inches of additional water mainly from a combination
of thermal expansion and accumulated sea level rise since the
tidal datum was established (1983-2001). High tide varies up to
90 minutes earlier or later along the Pacific Coast and through
the San Francisco Bay, respectively.

Information:
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.