Enter any address in Alameda County, California to see its FEMA flood zone
Flooding from standard flood events dominates Alameda County, accounting for 148 recorded events and 1 death over the last 30 years, alongside 27 flash flood events and 3 coastal flood events.
Recent impacts are illustrated by a series of storm systems that impacted the Bay Area and Central Coast from December 19 to December 25, 2025, disrupting Christmas holiday travel with flight delays at San Francisco International Airport and widespread power outages.
Property owners and residents should examine their specific FEMA flood zones, as historical NFIP claims vary significantly by designation. Zone A recorded 177 claims with an average payout of $16,634 and an average recorded water depth of 13 inches. Zone X recorded 120 claims with an average payout of $30,215 and an average recorded water depth of 35 inches. Zone X_UNSHADED logged 107 claims with an average payout of $7,020 and an average recorded water depth of 3 inches, while Zone X_SHADED recorded 36 claims averaging $22,892 in payouts with an average water depth of 2 inches. Properties with unknown zones recorded 128 claims averaging a $3,450 payout and an average water depth of 2 inches.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
86 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Alameda County, California has recorded 178 flood-related events since 1996 according to NOAA's Storm Events Database, including 27 flash floods and 148 river or area floods. The county has received 24 federal disaster declarations, 8 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1970–2023)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Winter Storms, Straight-line Winds, Flooding, Landslides, And Mudslides | Severe Storm | Feb 21, 2023 |
| Severe Winter Storms, Flooding, And Mudslides | Flood | Jan 8, 2023 |
| Severe Winter Storms, Flooding, Landslides, And Mudslides | Flood | Dec 27, 2022 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Winter Storms, Flooding, And Mudslides | Flood | Feb 1, 2017 |
| Severe Winter Storms, Flooding, And Mudslides | Severe Storm | Jan 18, 2017 |
| Severe Storms, Flooding, Landslides, And Mudslides | Severe Storm | Mar 29, 2006 |
| Severe Storms, Flooding, Mudslides, And Landslides | Severe Storm | Dec 17, 2005 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Dec 25, 2025 | 0.00K |
| Flood | Dec 24, 2025 | 0.00K |
| Flood | Dec 22, 2025 | 0.00K |
| Flood | Nov 17, 2025 | 0.00K |
| Flood | Nov 13, 2025 | 0.00K |
| Flood | Feb 13, 2025 | 0.00K |
| Flood | Feb 4, 2025 | 0.00K |
| Flood | Jan 31, 2024 | 0.00K |
| Flood | Dec 29, 2024 | 0.00K |
| Flood | Dec 27, 2024 | 0.00K |
Flash Flood — Dec 25, 2025
A series of storm systems impacted the Bay Area and Central Coast from December 19 to 25th, impacting Christmas holiday travel across the region. The most impactful systems arrived on Christmas Eve and Christmas Day. Two tornado warnings were issued for the coastal regions of San Mateo and Santa Cruz counties based off radar indicated rotation. San Francisco International Airport reported delay...
Flood — Dec 24, 2025
A series of storm systems impacted the Bay Area and Central Coast from December 19 to 25th, impacting Christmas holiday travel across the region. The most impactful systems arrived on Christmas Eve and Christmas Day. Two tornado warnings were issued for the coastal regions of San Mateo and Santa Cruz counties based off radar indicated rotation. San Francisco International Airport reported delay...
Flood — Dec 22, 2025
A series of storm systems impacted the Bay Area and Central Coast from December 19 to 25th, impacting Christmas holiday travel across the region. The most impactful systems arrived on Christmas Eve and Christmas Day. Two tornado warnings were issued for the coastal regions of San Mateo and Santa Cruz counties based off radar indicated rotation. San Francisco International Airport reported delay...
Flood — Nov 17, 2025
A low pressure system brought rain and winds to the Bay Area and Central Coast on November 16 and 17th. Special Marine Warnings and Special Weather Statements were issued due to isolated thunderstorms causing localized heavy rain and gusty winds. The main frontal rain band came through in the overnight hours, with isolated to scattered showers and some thunderstorms continuing into the 17th.
Flood — Nov 13, 2025
An rapidly intensifying low pressure system impacted the Bay Area and Central Coast on November 13, with the associated frontal systems and atmospheric river resulting in numerous flooding impacts and strong winds across the region. High Wind Warnings and Wind Advisories were issued throughout the Bay Area and Central Coast, with the High Wind Warnings focused on the immediate coastal areas. Ov...
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Alameda County, California:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Alameda County, California that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with a mortgage from a federally regulated or insured lender, or a federally backed loan, are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.