7,403 flood insurance claims·$131.8M paid·10 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Sonoma County, California. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
River and general flooding dominate the historical record in Sonoma County, accounting for 244 out of 312 total flood events recorded over the last 30 years, alongside 44 flash floods, 21 coastal floods, and 3 storm surge or tide events.
Recent history illustrates these impacts, such as an atmospheric river and intensifying low pressure system that brought localized flooding and strong winds on November 13, followed by another low pressure system on November 16 and 17. Additionally, a series of storm systems impacted the region from December 19 to 25, leading to widespread flooding issues during the holiday travel period.
Properties situated in FEMA Flood Zone A require the closest attention, as this zone accounts for the vast majority of historical National Flood Insurance Program claims in the county with 6,242 claims resulting in an average payout of $21,851 and an average recorded water depth of 15 inches. Residents in Zone X and unshaded Zone X areas should also remain attentive, having collectively recorded hundreds of claims with average water depths ranging from 13 to 18 inches.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
7% of Sonoma County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
6,689 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 14 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 1995, with 1,731 claims and $36.0M paid, the year of Severe Winter Storms, Flooding, Landslides, Mud Flows and Severe Winter Storms, Flooding Landslides, Mud Flow.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
164 NOAA storm reports from Sonoma County describe what happened, in the words of the forecasters who covered it. Read the California flood stories →
36 federal disaster declarations since 1964, 10 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Winter Storms, Flooding, Landslides, And Mudslides | Mar 9, 2023 |
| Severe Winter Storms, Straight-line Winds, Flooding, Landslides, And Mudslides | Feb 21, 2023 |
| Severe Winter Storms, Flooding, And Mudslides | Jan 8, 2023 |
| Severe Winter Storms, Flooding, Landslides, And Mudslides | Dec 27, 2022 |
| Glass Fire | Sep 27, 2020 |
| Wildfires | Sep 4, 2020 |
| Lnu Lightning Fire Complex | Aug 17, 2020 |
| Wildfires | Aug 14, 2020 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
312 since 1996: 44 flash floods, 244 river or area floods and 24 coastal floods or surges.
| Event | Date | Damage |
|---|---|---|
| Flood | Dec 26, 2025 | — |
| Flood | Dec 21, 2025 | — |
| Flood | Nov 17, 2025 | — |
| Flood | Nov 13, 2025 | — |
| Flood | Feb 13, 2025 | — |
| Flood | Feb 6, 2025 | — |
| Flood | Feb 5, 2025 | — · 1 killed |
| Flood | Feb 5, 2025 | $10 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Dec 26, 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 delays of at least 300 fl…
Flood · Dec 21, 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 delays of at least 300 fl…
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. Over 3,500 customers l…
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Sonoma County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.