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Sonoma County, California

Natural disaster risk, federal disaster history and flood insurance facts.

Relatively High overall risk
13th of 58highest risk in California
$605Mexpected losses a year
33federal declarations
1 in 91homes with flood insurance
Photo: U.S. Geological Survey, CC0

Sonoma County, California has a relatively high overall risk from natural hazards in FEMA's National Risk Index. Its risk score is in the top 1% of US counties. It ranks 13th of 58 counties in California. The costliest hazards here are earthquakes, inland flooding and wildfires. FEMA estimates about $605 million a year in expected losses, or roughly $1,238 per resident. Since 1964 it has been included in 33 federal disaster or emergency declarations for natural events (21 major disasters). The most recent was in April 2023 (severe winter storms, straight-line winds, flooding, landslides and mudslides). About 1 in 91 homes here carry federal flood insurance (1,790 policies). Since 1978, federal flood insurance has paid about $132 million on 7,403 claims here.

FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.

Top risks in Sonoma County

$284 million a yearExpected losses. Damaging events about once every 9 years.
  • Ask whether an older house is bolted to its foundation.
  • Consider separate earthquake insurance where risk is high.
$280 million a yearExpected losses. Damaging events about 3 times a year.
  • Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
  • Price a flood policy now. Most new federal policies take 30 days to start.
$16.8 million a yearExpected losses. Damaging events about once every 260 years.
  • Clear dry plants and debris within 5 feet of the house.
  • Get home insurance quotes early; availability varies by area.
HazardRatingScoreExpected loss a year
EarthquakeHigh99.5
$284M
Inland floodingHigh99.2
$280M
WildfireHigh98.2
$17M
DroughtHigh99.3
$14M
LandslideHigh99.8
$5M
Heat waveModerate88.8
$3M
Coastal floodingModerate68.6
$1M
LightningModerate58.7
$341K
TsunamiVery Low26.2
$244K
TornadoVery Low15.4
$163K
Strong windVery Low13.6
$119K
HailVery Low16.1
$60K
Winter weatherVery Low8.1
$6K
Volcanic activityLow85.0
$3K
AvalancheVery Low10.8
$10

Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is relatively low and community resilience is relatively high in FEMA's measures.

Federal disaster history

Recent disasters nationwide ›

Declarations by decade

Federal declarations for natural events that included Sonoma County. 2020s bar runs to November 2026.

By type

Fire11
Flood9
Severe Storm9
Drought1
Coastal Storm1
Freezing1

Most recent

Apr 3, 2023Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and MudslidesMajor disaster
Mar 10, 2023Severe Winter Storms, Flooding, Landslides, and MudslidesEmergency
Jan 14, 2023Severe Winter Storms, Flooding, Landslides, and MudslidesMajor disaster
Jan 9, 2023Severe Winter Storms, Flooding, and MudslidesEmergency
Oct 16, 2020WildfiresMajor disaster
Sep 27, 2020Glass FireFire management
Aug 22, 2020WildfiresMajor disaster
Aug 18, 2020Lnu Lightning Fire ComplexFire management
Oct 24, 2019Kincade FireFire management
May 17, 2019Severe Winter Storms, Flooding, Landslides, and MudslidesMajor disaster
Show all 33
Oct 10, 2017WildfiresMajor disaster
Oct 9, 2017Tubbs FireFire management
Oct 9, 2017Nuns FireFire management
Oct 9, 2017Partrick FireFire management
Apr 1, 2017Severe Winter Storms, Flooding, and MudslidesMajor disaster
Feb 14, 2017Severe Winter Storms, Flooding, and MudslidesMajor disaster
Sep 13, 2015Valley FireFire management
Jun 5, 2006Severe Storms, Flooding, Landslides, and MudslidesMajor disaster
Feb 3, 2006Severe Storms, Flooding, Mudslides, and LandslidesMajor disaster
Sep 13, 2005Hurricane Katrina EvacuationEmergency
Sep 4, 2004Ca-Geysers Fire-09-04-2004Fire management
Feb 9, 1998Severe Winter Storms and FloodingMajor disaster
Jan 4, 1997Severe Storms, Flooding, Mud and LandslidesMajor disaster
Mar 12, 1995Severe Winter Storms, Flooding Landslides, Mud FlowMajor disaster
Jan 10, 1995Severe Winter Storms, Flooding, Landslides, Mud FlowsMajor disaster
Feb 3, 1993Severe Winter Storm, Mud & Land Slides, & FloodingMajor disaster
Feb 11, 1991Severe FreezeMajor disaster
Feb 21, 1986Severe Storms & FloodingMajor disaster
Feb 9, 1983Coastal Storms, Floods, Slides & TornadoesMajor disaster
Jan 7, 1982Severe Storms, Flood, Mudslides & High TideMajor disaster
Jan 20, 1977DroughtEmergency
Jan 26, 1969Severe Storms & FloodingMajor disaster
Dec 24, 1964Heavy Rains & FloodingMajor disaster

California also had 35 statewide declarations that did not name single counties.

Storm history since 1958

Tornado risk by county ›

The National Weather Service has logged 423 storm reports in Sonoma County since 1958, with 10 deaths and 9 injuries and about $245 million in reported damage. The strongest on record here was an F2 tornado on June 1, 1958.

13tornadoes
21hail reports, largest 0.75 inches
1damaging thunderstorm winds
300floods and flash floods

Strongest tornadoes

DateStrengthNearHurt / killed
Jun 1, 1958F2–0 / 0
Dec 5, 1998F1Santa Rosa0 / 0
Dec 2, 1992F1–0 / 0
Jan 27, 2005F1Jenner0 / 0
Mar 18, 2011EF1Santa Rosa0 / 0

Most damaging storms

DateTypeNearDamage
Dec 31, 2005FloodCountywide$107M
Jan 1, 2006FloodCountywide$107M
Jun 4, 2011Heavy RainAnnapolis$20M
Feb 3, 1998Flash FloodRio Nido$5M
Feb 2, 1998Flash FloodPetaluma$2M
Dec 5, 1998TornadoSanta Rosa$1M

Source: NOAA Storm Events Database, county-based reports through Jan 5, 2026. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.

Flood insurance in Sonoma County

Check your address flood zone ›
1.1%of homes have federal flood insurance (1,790 policies)
31.3%of homes in mapped high-risk flood zones are insured
$132 millionpaid on 7,403 flood claims since 1978
1995costliest year, with $35.9 million paid

National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.

Homes in Sonoma County

$815,500median home value (California $734,700, US $332,700)
1979median year homes were built (California 1976, US 1980)
52%of homes built before 1980, before many modern wind, quake and flood building rules
4.8%of homes are mobile homes, which are the least safe in tornadoes and high winds

Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 207,699 housing units.

Compare in California

All 58 ›
Largest countiesOverall riskTop hazard
Los Angeles CountyVery HighEarthquake
San Diego CountyVery HighInland flooding
Orange CountyVery HighEarthquake
Riverside CountyVery HighInland flooding
San Bernardino CountyVery HighInland flooding
Santa Clara CountyVery HighEarthquake
Alameda CountyVery HighEarthquake
Sacramento CountyHighInland flooding

Neighboring counties

CountyOverall riskDeclarations
Contra Costa CountyVery High19
Solano CountyHigh28
Marin CountyHigh24
Napa CountyHigh37
Mendocino CountyHigh30
Lake CountyModerate33

Common questions about Sonoma County

What is the biggest natural hazard in Sonoma County?

Earthquake has the highest expected yearly losses in Sonoma County, about $284 million a year in FEMA's estimate. Inland flooding is second at $280 million.

How many federal disasters has Sonoma County had?

Sonoma County has been included in 33 federal disaster or emergency declarations for natural events since 1964, including 21 major disasters. The most recent was Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides in April 2023.

Is Sonoma County a high-risk place to live?

Its overall rating is Relatively High, 13th highest of 58 in California. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.

Do I need flood insurance in Sonoma County?

Standard home insurance does not cover flooding. About 1 in 91 homes in Sonoma County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.

How many tornadoes has Sonoma County had?

NOAA records list 13 tornadoes in Sonoma County since 1950. The strongest was an F2 tornado on June 1, 1958. The weather service has also logged 21 hail reports and 300 floods here.

Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.