Washington County, Oregon
Natural disaster risk, federal disaster history and flood insurance facts.
Washington County, Oregon has a relatively high overall risk from natural hazards in FEMA's National Risk Index. Its risk score is higher than 96% of US counties. It ranks 3rd of 36 counties in Oregon. The costliest hazards here are earthquakes, inland flooding and heat waves. FEMA estimates about $270 million a year in expected losses, or roughly $450 per resident. Since 1964 it has been included in 15 federal disaster or emergency declarations for natural events (10 major disasters). The most recent was in August 2024 (Lee Falls Fire). Fewer than 1 in 100 homes here carry federal flood insurance (1,044 policies). Since 1978, federal flood insurance has paid about $5.5 million on 408 claims here, including $3.0 million for floods in 1996.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Washington County
- Ask whether an older house is bolted to its foundation.
- Consider separate earthquake insurance where risk is high.
- 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.
- Check that cooling works before summer.
- Know where the nearest cooling center is.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Earthquake | 99.0 | $163M | ||
| Inland flooding | 93.9 | $81M | ||
| Heat wave | 96.6 | $11M | ||
| Cold wave | 90.1 | $9M | ||
| Tornado | 53.1 | $2M | ||
| Strong wind | 80.1 | $2M | ||
| Ice storm | 91.4 | $1M | ||
| Lightning | 81.7 | $1M | ||
| Winter weather | 75.2 | $216K | ||
| Hail | 29.8 | $151K | ||
| Wildfire | 50.9 | $65K | ||
| Landslide | 85.8 | $43K | ||
| Volcanic activity | 89.3 | $16K | ||
| Avalanche | 10.2 | $11 | ||
| Drought | 12.2 | $0 |
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 very 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 Washington County. 2020s bar runs to November 2026.
By type
Most recent
Show all 15
Oregon also had 42 statewide declarations that did not name single counties.
Storm history since 1954
Tornado risk by county ›The National Weather Service has logged 69 storm reports in Washington County since 1954, with 2 deaths and 0 injuries and about $5.7 million in reported damage. The strongest on record here was an F1 tornado on November 12, 1991.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Nov 12, 1991 | F1 | – | 0 / 0 |
| Oct 29, 2018 | EF0 | Forest Grove | 0 / 0 |
| Jun 23, 1966 | F0 | – | 0 / 0 |
| Jun 18, 2004 | F0 | Sherwood | 0 / 0 |
| Oct 22, 1954 | F0 | – | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Dec 7, 2015 | Flood | Dilley | $2M |
| Dec 3, 2007 | Flood | Dilley | $2M |
| Dec 9, 2015 | Flood | Dilley | $283K |
| Aug 5, 2003 | Lightning | Tigard | $150K |
| Dec 18, 2015 | Flood | Dilley | $141K |
| Jun 25, 2014 | Heavy Rain | Beaverton | $140K |
Source: NOAA Storm Events Database, county-based reports through Nov 20, 2024. 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 Washington County
Check your address flood zone ›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 Washington County
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; 243,278 housing units.
Compare in Oregon
All 36 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Multnomah County | Earthquake | |
| Washington County | Earthquake | |
| Clackamas County | Earthquake | |
| Lane County | Inland flooding | |
| Marion County | Earthquake | |
| Jackson County | Inland flooding | |
| Deschutes County | Inland flooding | |
| Linn County | Earthquake |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Multnomah County | 10 | |
| Clackamas County | 21 | |
| Yamhill County | 17 | |
| Columbia County | 14 | |
| Clatsop County | 16 | |
| Tillamook County | 22 |
Common questions about Washington County
What is the biggest natural hazard in Washington County?
Earthquake has the highest expected yearly losses in Washington County, about $163 million a year in FEMA's estimate. Inland flooding is second at $80.6 million.
How many federal disasters has Washington County had?
Washington County has been included in 15 federal disaster or emergency declarations for natural events since 1964, including 10 major disasters. The most recent was Lee Falls Fire in August 2024.
Is Washington County a high-risk place to live?
Its overall rating is Relatively High, 3rd highest of 36 in Oregon. 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 Washington County?
Standard home insurance does not cover flooding. About 1 in 167 homes in Washington 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 Washington County had?
NOAA records list 6 tornadoes in Washington County since 1950. The strongest was an F1 tornado on November 12, 1991. The weather service has also logged 8 hail reports and 26 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.