Napa County, California: Natural Disaster Risk and History
Napa County, California has a Relatively High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 95.3 out of 100, higher than about 95% of US counties, with drought, landslides and earthquakes scoring highest of its 18 hazards and $186 million a year in expected losses.
OpenFEMA lists 37 federal disaster declarations that included Napa County since 1964, not counting 2 for COVID-19; the latest is DR-4699-CA (Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides, declared 3 April 2023). NOAA's Storm Prediction Center recorded 1 tornado touching Napa County from 1950 to 2025.
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Population 137,956 Buildings worth $38 billion Area 797 sq mi Risk rank in California 29 of 58 FIPS 06055
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Drought | Very High | 99.5 | $21 million | about 6 a year | 2,037 |
| Landslide | Relatively High | 98.7 | $1.1 million | about 42 a year | — |
| Earthquake | Relatively High | 98.4 | $67 million | about once every 8.4 years | — |
| Wildfire | Relatively Moderate | 96.0 | $4.9 million | about once every 219 years | — |
| Inland flooding | Relatively High | 95.8 | $90 million | about 1.1 a year | 31 |
| Coastal flooding | Relatively Moderate | 68.2 | $987,421 | about 3.6 a year | — |
| Heat wave | Relatively Low | 66.8 | $794,117 | about 7.7 a year | 101 |
| Volcanic activity | Very Low | 60.3 | $33 | rarer than once in 1,000 years | 1 |
| Lightning | Relatively Low | 30.2 | $110,343 | about 4.2 a year | 9,111 strikes |
| Tornado | Very Low | 18.3 | $210,636 | about once every 11 years | 1 |
| Avalanche | Very Low | 9.2 | $7 | about once every 100 years | 0 |
| Hail | Very Low | 8.5 | $24,782 | about once every 24 years | 1.6 |
| Strong wind | Very Low | 8.3 | $61,180 | about once every 35 years | 2 |
| Winter weather | Very Low | 4.2 | $2,920 | about 1.1 a year | 22 |
| Tsunami | Very Low | 3.1 | $3,259 | about once every 3.0 years | 73 |
| Cold wave | No Rating | 0.0 | — | — | 0 |
| Hurricane | Not Applicable | — | — | — | — |
| Ice storm | Not Applicable | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 37
Most common: Fire 13, Severe Storm 10, Flood 8, Earthquake 2.
| Decade | Declarations | Incident types |
|---|---|---|
| 1960s | 1 | Flood |
| 1970s | 1 | Drought |
| 1980s | 2 | Flood, Coastal Storm |
| 1990s | 7 | Severe Storm ×4, Fire, Flood, Freezing |
| 2000s | 5 | Severe Storm ×2, Fire, Hurricane, Earthquake |
| 2010s | 13 | Fire ×7, Severe Storm ×3, Flood ×2, Earthquake |
| 2020s | 8 | Fire ×4, Flood ×3, Severe Storm |
The last 10
Widest declarations that included Napa County
- Hurricane Katrina Evacuation (2005, EM-3248-CA): 58 California counties designated.
- Severe Winter Storms, Flooding Landslides, Mud Flow (1995, DR-1046-CA): 57 California counties designated.
- Severe Storms, Flooding, Mud and Landslides (1997, DR-1155-CA): 48 California counties designated.
Named storms in its declarations: Hurricane Katrina (2005).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. California also had 30 statewide declarations with no county list.
Tornado record since 1950 1
| Tornadoes touching the county | 1 |
|---|---|
| Strongest-rated | (E)F0 ×1 |
| Peak month | April (1) |
| Deadliest | — |
| Longest path | 27 Apr 2016, EF0, 0.2 mi path |
| Most recent | 27 Apr 2016, EF0, 0.2 mi path |
| Deaths / injuries on those paths | 0 / 0 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 |
Deaths and injuries are for each tornado's whole path, which can run beyond this county. F-scale ratings before February 2007, Enhanced Fujita (EF) after.
How Napa County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Napa County (this page) | — | Relatively High | 95.3 | Drought |
| Yolo County | 42 km | Relatively Moderate | 91.4 | Drought |
| Solano County | 44 km | Relatively High | 97.0 | Drought |
| Sonoma County | 49 km | Relatively High | 99.1 | Landslide |
| Marin County | 59 km | Relatively High | 96.4 | Landslide |
| Contra Costa County | 74 km | Very High | 99.5 | Earthquake |
Nearest by distance between county centres. Every county in California, ranked.
Vulnerability and resilience
| Social vulnerability | Relatively Low 38.5 |
|---|---|
| Community resilience | Relatively High 76.0 |
| Community risk factor | 1.03 |
| Expected annual loss, all hazards | $186 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for Napa County's main hazards
- Right now: National Weather Service alerts for California · all official warnings on Global Incident Tracker.
- Drought: Drought monitor for California
- Landslide: Landslides recorded
- Earthquake: Earthquakes today · Earthquake safety guide
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about Napa County
What natural disasters is Napa County, California most at risk from?
Napa County, California has a Relatively High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 95.3 out of 100, higher than about 95% of US counties, with drought, landslides and earthquakes scoring highest of its 18 hazards and $186 million a year in expected losses.
How many federal disaster declarations has Napa County had?
OpenFEMA lists 37 federal disaster declarations that included Napa County since 1964, not counting 2 for COVID-19; the latest is DR-4699-CA (Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides, declared 3 April 2023). Another 30 California declarations were made statewide without a county list.
How many tornadoes have hit Napa County?
NOAA's Storm Prediction Center recorded 1 tornado touching Napa County from 1950 to 2025.
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.