San Juan County, Washington
Natural disaster risk, federal disaster history and flood insurance facts.
San Juan County, Washington has a very low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 65% of US counties. It ranks 33rd of 39 counties in Washington. The costliest hazards here are inland flooding, earthquakes and cold waves. FEMA estimates about $9.9 million a year in expected losses, or roughly $558 per resident. Since 1980 it has been included in 10 federal disaster or emergency declarations for natural events (9 major disasters). The most recent was in January 2022 (severe storms, straight-line winds, flooding, landslides and mudslides). Fewer than 1 in 100 homes here carry federal flood insurance (95 policies).
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in San Juan County
- 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.
- Ask whether an older house is bolted to its foundation.
- Consider separate earthquake insurance where risk is high.
- Insulate pipes in outside walls, crawl spaces and garages.
- Know how to shut off the main water valve.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Inland flooding | 42.1 | $5M | ||
| Earthquake | 89.4 | $4M | ||
| Cold wave | 31.6 | $398K | ||
| Coastal flooding | 58.4 | $354K | ||
| Winter weather | 60.0 | $79K | ||
| Tsunami | 6.2 | $31K | ||
| Heat wave | 13.9 | $28K | ||
| Wildfire | 41.3 | $25K | ||
| Lightning | 5.5 | $15K | ||
| Ice storm | 19.1 | $13K | ||
| Tornado | 4.4 | $13K | ||
| Landslide | 62.3 | $3K | ||
| Strong wind | 1.1 | $1K | ||
| Hail | 1.1 | $808 | ||
| Volcanic activity | 37.1 | $4 |
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 high and community resilience is very high in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included San Juan County. 2020s bar runs to November 2026.
By type
Most recent
Washington also had 51 statewide declarations that did not name single counties.
Storm history since 2001
Tornado risk by county ›The National Weather Service has logged 4 storm reports in San Juan County since 2001 and about $510,000 in reported damage. No tornadoes are on record here.
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Nov 15, 2021 | Flood | Deer Harbor | $475K |
| Jun 18, 2004 | Thunderstorm Wind | Orcas | $25K |
| Sep 3, 2015 | Heavy Rain | Friday Harbor | $10K |
Source: NOAA Storm Events Database, county-based reports through Nov 15, 2021. 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 San Juan 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 San Juan 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; 13,990 housing units.
Compare in Washington
All 39 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| King County | Earthquake | |
| Pierce County | Earthquake | |
| Snohomish County | Earthquake | |
| Spokane County | Inland flooding | |
| Clark County | Inland flooding | |
| Thurston County | Earthquake | |
| Kitsap County | Earthquake | |
| Yakima County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Whatcom County | 24 | |
| Skagit County | 27 | |
| Island County | 20 | |
| Clallam County | 27 | |
| Jefferson County | 27 |
Common questions about San Juan County
What is the biggest natural hazard in San Juan County?
Inland flooding has the highest expected yearly losses in San Juan County, about $4.6 million a year in FEMA's estimate. Earthquake is second at $4.3 million.
How many federal disasters has San Juan County had?
San Juan County has been included in 10 federal disaster or emergency declarations for natural events since 1980, including 9 major disasters. The most recent was Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides in January 2022.
Is San Juan County a high-risk place to live?
Its overall rating is Very Low, 33rd highest of 39 in Washington. 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 San Juan County?
Standard home insurance does not cover flooding. About 1 in 143 homes in San Juan 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 San Juan County had?
NOAA records list 0 tornadoes in San Juan County since 1950. The weather service has also logged 0 hail reports and 1 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.