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Williamson County, Texas

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

Relatively Moderate overall risk
24th of 254highest risk in Texas
$137Mexpected losses a year
23federal declarations
1 in 91homes with flood insurance
Photo: Larry D. Moore, CC BY 4.0

Williamson County, Texas has a moderate overall risk from natural hazards in FEMA's National Risk Index. Its risk score is higher than 90% of US counties. It ranks 24th of 254 counties in Texas. The costliest hazards here are inland flooding, cold waves and tornadoes. FEMA estimates about $137 million a year in expected losses, or roughly $225 per resident. Since 1974 it has been included in 23 federal disaster or emergency declarations for natural events (12 major disasters). The most recent was in July 2025 (severe storms, straight-line winds and flooding). About 1 in 91 homes here carry federal flood insurance (1,949 policies). Since 1978, federal flood insurance has paid about $22 million on 741 claims here, including $11 million for floods in 2010.

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

Top risks in Williamson County

$71 million a yearExpected losses. Damaging events about 4 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.
$21.3 million a yearExpected losses. Damaging events about once every 2 years.
  • Insulate pipes in outside walls, crawl spaces and garages.
  • Know how to shut off the main water valve.
$16.5 million a yearExpected losses. Damaging events about once every 2 years.
  • Pick a shelter spot: a basement, or an inside room on the lowest floor with no windows.
  • Turn on emergency alerts on your phone and keep a weather radio.
HazardRatingScoreExpected loss a year
Inland floodingModerate91.3
$71M
Cold waveHigh95.9
$21M
TornadoHigh93.9
$17M
HailHigh98.7
$14M
Heat waveModerate91.0
$5M
LightningHigh88.8
$2M
WildfireLow87.8
$2M
Winter weatherVery High96.8
$1M
Strong windModerate55.9
$1M
DroughtModerate72.4
$964K
HurricaneLow69.0
$860K
Ice stormModerate72.5
$403K
EarthquakeVery Low36.5
$197K
LandslideVery Low24.1
$278

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 very high in FEMA's measures.

Federal disaster history

Recent disasters nationwide ›

Declarations by decade

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

By type

Fire8
Severe Storm4
Hurricane4
Flood3
Severe Ice Storm2
Drought1

Most recent

Jul 6, 2025Severe Storms, Straight-Line Winds, and FloodingMajor disaster
Apr 21, 2023Severe Winter StormMajor disaster
Feb 19, 2021Severe Winter StormsMajor disaster
Feb 14, 2021Severe Winter StormEmergency
May 29, 2015Severe Storms, Tornadoes, Straight-Line Winds and FloodingMajor disaster
Sep 9, 2011WildfiresMajor disaster
Sep 6, 2011Moonglow FireFire management
Aug 15, 2011Horseshoe FireFire management
Jun 16, 2011Grand Mesa FireFire management
Sep 10, 2008Hurricane IkeEmergency
Show all 23
Aug 7, 2008Florence FireFire management
Mar 14, 2008WildfiresEmergency
Jun 29, 2007Severe Storms, Tornadoes, and FloodingMajor disaster
Jan 11, 2006Extreme Wildfire ThreatMajor disaster
Sep 24, 2005Hurricane RitaMajor disaster
Sep 21, 2005Hurricane RitaEmergency
Sep 2, 2005Hurricane Katrina EvacuationEmergency
Sep 1, 1999Extreme Fire HazardsEmergency
Aug 26, 1998Tropical Storm CharleyMajor disaster
Sep 10, 1993Extreme Fire HazardEmergency
Dec 26, 1991Severe ThunderstormsMajor disaster
May 19, 1989Severe Storms, Tornadoes & FloodingMajor disaster
Nov 30, 1974Severe Storms & FloodingMajor disaster

Texas also had 106 statewide declarations that did not name single counties.

Storm history since 1954

Tornado risk by county ›

The National Weather Service has logged 916 storm reports in Williamson County since 1954, with 36 deaths and 84 injuries and about $461 million in reported damage. The strongest on record here was an F5 tornado on May 27, 1997 near Jarrell.

71tornadoes
458hail reports, largest 4 inches
209damaging thunderstorm winds
168floods and flash floods

Strongest tornadoes

DateStrengthNearHurt / killed
May 27, 1997F5Jarrell12 / 27
May 17, 1989F3–28 / 1
Apr 7, 1980F3–2 / 1
May 27, 1997F3Cedar Park15 / 0
Apr 30, 1954F3–6 / 0

Most damaging storms

DateTypeNearDamage
Sep 24, 2023HailRound Rock$300M
May 27, 1997TornadoCedar Park$70M
May 27, 1997TornadoJarrell$40M
Jul 5, 2025Flash FloodAndice$25M
May 25, 2015Flash FloodHutto$7M
May 17, 1989Tornado–$3M

Source: NOAA Storm Events Database, county-based reports through Jun 15, 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.

Hurricanes and tropical storms

Hurricane risk by county ›

Since 1897, 1 hurricane and 9 tropical storms have passed within 65 miles of the center of Williamson County, 3 of them since 1950. The strongest was an unnamed hurricane in 1900, with top winds near 85 mph about 62 miles away.

1hurricanes
0major hurricanes (Category 3+)
9tropical storms
1973most recent: Delia

Strongest storms nearby

DateStormStrengthClosest
Sep 9, 1900UnnamedCategory 1, 85 mph62 mi
Sep 12, 1961CarlaTropical storm, 70 mph59 mi
Aug 14, 1932UnnamedTropical storm, 55 mph54 mi
Aug 17, 1915UnnamedTropical storm, 50 mph62 mi
Sep 13, 1897UnnamedTropical storm, 50 mph60 mi
Jun 24, 1968CandyTropical storm, 50 mph65 mi

Most recent storms

DateStormStrengthClosest
Sep 6, 1973DeliaTropical storm, 45 mph63 mi
Jun 24, 1968CandyTropical storm, 50 mph65 mi
Sep 12, 1961CarlaTropical storm, 70 mph59 mi
Aug 28, 1945UnnamedTropical storm, 40 mph64 mi
Jul 28, 1943UnnamedTropical storm, 45 mph64 mi
Aug 14, 1932UnnamedTropical storm, 55 mph54 mi

Source: NOAA National Hurricane Center best-track records (HURDAT2), 1851 to 2025 for the Atlantic and 1949 to 2025 for the eastern Pacific. A storm counts if its track passed within 65 miles of the county's center while it was a tropical storm or hurricane. Strength is the storm's top sustained wind at that point, not the wind measured in the county. Older storms over the open sea were sometimes missed.

Flood insurance in Williamson County

Check your address flood zone ›
1.1%of homes have federal flood insurance (1,949 policies)
45.8%of homes in mapped high-risk flood zones are insured
$22.2 millionpaid on 741 flood claims since 1978
2010costliest year, with $10.7 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 Williamson County

$447,000median home value (Texas $283,800, US $332,700)
2006median year homes were built (Texas 1992, US 1980)
9%of homes built before 1980, before many modern wind, quake and flood building rules
1.9%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; 262,644 housing units.

Compare in Texas

All 254 ›
Largest countiesOverall riskTop hazard
Harris CountyVery HighInland flooding
Dallas CountyVery HighInland flooding
Tarrant CountyHighInland flooding
Bexar CountyHighInland flooding
Travis CountyHighInland flooding
Collin CountyHighTornado
Denton CountyHighTornado
Hidalgo CountyHighHurricane

Neighboring counties

CountyOverall riskDeclarations
Travis CountyHigh35
Bell CountyModerate20
Bastrop CountyModerate29
Burnet CountyLow22
Milam CountyLow20
Lee CountyVery Low20

Common questions about Williamson County

What is the biggest natural hazard in Williamson County?

Inland flooding has the highest expected yearly losses in Williamson County, about $71 million a year in FEMA's estimate. Cold wave is second at $21.3 million.

How many federal disasters has Williamson County had?

Williamson County has been included in 23 federal disaster or emergency declarations for natural events since 1974, including 12 major disasters. The most recent was Severe Storms, Straight-Line Winds, and Flooding in July 2025.

Is Williamson County a high-risk place to live?

Its overall rating is Relatively Moderate, 24th highest of 254 in Texas. 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 Williamson County?

Standard home insurance does not cover flooding. About 1 in 91 homes in Williamson 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 Williamson County had?

NOAA records list 71 tornadoes in Williamson County since 1950. The strongest was an F5 tornado on May 27, 1997 near Jarrell. The weather service has also logged 458 hail reports and 168 floods here.

How many hurricanes have hit Williamson County?

NOAA's hurricane records show 1 hurricane and 9 tropical storms passing within 65 miles of the center of Williamson County. The strongest was an unnamed hurricane in 1900, with winds near 85 mph.

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.