Natural hazards · Thornton

Thornton, CA natural hazards

Most of the natural-hazard damage FEMA expects in Thornton comes from drought, and overall the risk is very high for a U.S. community. 1 federal disaster brought FEMA money into town.

FEMA National Risk Index, December 2025 · OpenFEMA claims, aid & declarations

Expected damage

How exposed is Thornton?

Very high

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Thornton to be higher than in 85% of U.S. communities, mostly from drought.

Drought76%Earthquakes15%Inland flooding9%Everything else1%

By hazard

What Thornton faces

Each hazard’s share of the damage FEMA expects here, and how that compares with the rest of the country.

Drought

76% of expected damage

Recorded about 70 times a year in the area

Earthquakes

15% of expected damage

Well above average · higher than 94% of U.S. places

Inland flooding

9% of expected damage

Well above average · higher than 76% of U.S. places

Recorded about once a year in the area

Lower here

TornadoesHailWinter weatherHeat wavesWildfireLandslidesStrong windLightningVolcanic activity

Not a risk here

Coastal floodingHurricanesIce stormsCold wavesAvalanchesTsunamis

Flood risk changes street by street. Check a specific address on FEMA’s flood map, and ask about flood insurance before you buy.

Flood insurance claims

Does Thornton flood?

FEMA's records show no paid flood insurance claims in Thornton.

of homes in flood zones
are insured

of all homes
are insured

No community discount. Thornton isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.

Insurance rates: San Joaquin County.

Disasters that hit Thornton

1 federal disaster brought FEMA money here

Disasters the President declared that paid out in Thornton itself: aid to households, or repair grants to Thornton.

Brought FEMA money into ThorntonDeclared for San Joaquin County only

2022

Severe Winter Storms, Flooding, Landslides, and Mudslides

11 households applied for aid $14K aid approved

San Joaquin County has had 23 natural disasters declared since 1953, most often floods and severe storms.

About these numbers

How to read this page

An average, not a forecastFEMA’s National Risk Index estimates the damage 18 kinds of natural hazards cause in a typical year, from decades of records and models. A quiet decade can follow a bad year.

Compared by rate“Higher than N%” compares yearly damage as a share of what’s here, so a big city isn’t rated riskier just for having more buildings. Thornton is smaller than a census tract, so it shares the figures of the tract around its center.

Money that reached townFlood claims are matched to Thornton’s own flood-insurance community; household aid to the registrant’s city; repair grants to Thornton. FEMA’s model follows property values, so a place that recently lost many homes can rate lower than it feels.

Sources: FEMA National Risk Index (December 2025); OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Census tracts: U.S. Census Bureau.