Harris County, Texas: Natural Disaster Risk and History
Harris County, Texas has a Very High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 99.9 out of 100, higher than about 99% of US counties, with inland (river and flash) flooding, hurricanes and tornadoes scoring highest of its 18 hazards and $2.2 billion a year in expected losses.
OpenFEMA lists 39 federal disaster declarations that included Harris County since 1973, not counting 2 for COVID-19; the latest is DR-4798-TX (Hurricane Beryl, declared 9 July 2024). NOAA's Storm Prediction Center recorded 253 tornadoes touching Harris County from 1950 to 2025.
Live weather alerts for Texas All official warnings Latest FEMA declarations
Population 4,726,200 Buildings worth $839 billion Area 1,795 sq mi Risk rank in Texas 1 of 254 FIPS 48201
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Inland flooding | Very High | 100.0 | $1.1 billion | about 5.1 a year | 144 |
| Hurricane | Very High | 100.0 | $458 million | about once every 5.4 years | 75 |
| Tornado | Very High | 100.0 | $407 million | about 1.6 a year | 150 |
| Cold wave | Very High | 99.9 | $118 million | about once every 2.1 years | 9.1 |
| Lightning | Very High | 99.9 | $8.6 million | about 75 a year | 3,820,963 strikes |
| Heat wave | Very High | 99.7 | $80 million | about 15 a year | 250 |
| Ice storm | Very High | 99.6 | $4.1 million | about once every 1.1 years | 61 |
| Strong wind | Very High | 99.3 | $7.7 million | about 1.5 a year | 58 |
| Earthquake | Relatively Moderate | 92.1 | $5.9 million | rarer than once in 1,000 years | — |
| Hail | Relatively Moderate | 92.0 | $1.6 million | about 2.4 a year | 90 |
| Winter weather | Relatively High | 88.8 | $295,947 | about 1.1 a year | 21 |
| Landslide | Relatively Moderate | 88.4 | $36,555 | about once every 4.2 years | — |
| Wildfire | Relatively Low | 85.4 | $562,161 | about once every 893 years | — |
| Coastal flooding | Relatively High | 83.2 | $2.5 million | about 3.8 a year | — |
| Drought | Relatively Moderate | 75.1 | $549,870 | about 16 a year | 861 |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Insufficient Data | — | — | — | — |
| Volcanic activity | 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 39
Most common: Hurricane 12, Flood 12, Severe Storm 8, Fire 3.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 4 | Flood ×3, Severe Storm |
| 1980s | 4 | Flood ×2, Severe Storm, Hurricane |
| 1990s | 7 | Flood ×3, Severe Storm ×2, Fire, Tornado |
| 2000s | 11 | Hurricane ×7, Severe Storm ×2, Fire, Coastal Storm |
| 2010s | 7 | Flood ×3, Severe Storm ×2, Hurricane, Fire |
| 2020s | 6 | Hurricane ×3, Severe Ice Storm ×2, Flood |
The last 10
Widest declarations that included Harris County
- Severe Winter Storms (2021, DR-4586-TX): 254 Texas counties designated.
- Severe Winter Storm (2021, EM-3554-TX): 254 Texas counties designated.
- Extreme Wildfire Threat (2006, DR-1624-TX): 254 Texas counties designated.
Named storms in its declarations: Hurricane Beryl (2024), Hurricane Hanna (2020), Tropical Storm Imelda (2019), Hurricane Harvey (2017), Hurricane Ike (2008), Hurricane Gustav (2008), Tropical Storm Erin (2007), Hurricane Dean (2007), Hurricane Rita (2005), Hurricane Katrina (2005), Tropical Storm Allison (2001), Hurricane Georges (1998), Tropical Storm Charley (1998), Tropical Storm Allison (1989), Hurricane Alicia (1983).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Texas also had 101 statewide declarations with no county list.
Tornado record since 1950 253
| Tornadoes touching the county | 253 |
|---|---|
| Strongest-rated | (E)F4 ×1 |
| Peak month | May (39) |
| Deadliest | 5 Feb 1986, F3, 5 mi path, 2 killed, 0 injured |
| Longest path | 21 Nov 1992, F3, 32 mi path, 0 killed, 1 injured |
| Most recent | 24 Nov 2025, EF1, 2.6 mi path |
| Deaths / injuries on those paths | 12 / 321 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 129 | 81 | 33 | 9 | 1 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 6 | 18 | 56 | 51 | 42 | 38 | 27 | 15 |
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 Harris County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Harris County (this page) | — | Very High | 99.9 | Inland flooding |
| Montgomery County | 50 km | Relatively High | 95.7 | Lightning |
| Fort Bend County | 52 km | Relatively High | 97.5 | Lightning |
| Waller County | 60 km | Relatively Low | 70.3 | Drought |
| Liberty County | 65 km | Relatively Low | 79.5 | Lightning |
| Galveston County | 66 km | Relatively High | 95.4 | Cold wave |
Nearest by distance between county centres. Every county in Texas, ranked.
Vulnerability and resilience
| Social vulnerability | Relatively High 67.9 |
|---|---|
| Community resilience | Very Low 17.9 |
| Community risk factor | 1.33 |
| Expected annual loss, all hazards | $2.2 billion |
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 Harris County's main hazards
- Right now: National Weather Service alerts for Texas · all official warnings on Global Incident Tracker.
- Inland flooding: Flood safety: why shallow water kills · Floods recorded
- Hurricane: Is there a hurricane now? · Cyclone preparation
- Tornado: Is there a tornado warning now?
- 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 Harris County
What natural disasters is Harris County, Texas most at risk from?
Harris County, Texas has a Very High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 99.9 out of 100, higher than about 99% of US counties, with inland (river and flash) flooding, hurricanes and tornadoes scoring highest of its 18 hazards and $2.2 billion a year in expected losses.
How many federal disaster declarations has Harris County had?
OpenFEMA lists 39 federal disaster declarations that included Harris County since 1973, not counting 2 for COVID-19; the latest is DR-4798-TX (Hurricane Beryl, declared 9 July 2024). Another 101 Texas declarations were made statewide without a county list.
How many tornadoes have hit Harris County?
NOAA's Storm Prediction Center recorded 253 tornadoes touching Harris County from 1950 to 2025. The deadliest: 5 Feb 1986, F3, 5 mi path, 2 killed, 0 injured (deaths and injuries are for the whole path).
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.