Photo: Piperpet · CC BY-SA 4.0FEMA puts Thonotosassa’s expected hazard damage per building above that of 74% of U.S. towns, led by river and rain flooding
On FEMA’s National Risk Index, Thonotosassa gets a C for hazard risk: higher expected damage per building than 74% of U.S. towns, #247 of 638 in Florida. Most of that expected damage is river and rain flooding (45%), then hurricanes (44%). Flood insurance has paid 51 claims here since 1988.
Graded on FEMA’s expected yearly building damage per dollar of building value (NRI v1.20, December 2025), weighted by where residents live; flood claims are shown, not graded. How hazard risk is graded
What Thonotosassa faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
River and rain flooding
Hurricanes
Tornadoes
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
What’s behind Thonotosassa’s grade
River and rain flooding is 45% of the building damage FEMA expects in Thonotosassa, and Thonotosassa’s rate of river and rain flooding damage is lower than 54% of U.S. census tracts. Hurricanes add 44%, at a rate in the top 9% of U.S. census tracts.
C #247 of 638 in Florida; higher expected damage per building than 74% of U.S. towns (21,298).
Thonotosassa’s residents live in 5 census tracts; FEMA’s figures are combined by where they live.
The typical Florida town has higher expected damage than 79% of U.S. towns; within the state, Thonotosassa has less expected damage per building than 61% of Florida towns.
In dollars, FEMA expects about $5.3M a year in losses across Thonotosassa: $3.2M to buildings, the rest to people and crops.
Does Thonotosassa flood? Sometimes: 51 flood claims since 1988
Every paid claim on a federal flood insurance policy in Thonotosassa, from FEMA’s records: 8.5 per 1,000 homes, more than 71% of the 13,809 U.S. towns with a flood insurance record.
- Hurricane Milton32 claims · $3.8M
- Hurricane Frances3 claims · $51K
- Hurricane Irma2 claims · $31K
Thonotosassa isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Hillsborough County.9 federal disasters brought FEMA money to Thonotosassa
Disasters that paid out in Thonotosassa itself (aid to households or repair grants to Thonotosassa), newest first, with that year’s flood claims.
- 2024Hurricane Milton2,702 households applied for aid$2.6M aid approved32 flood claims paid for it, $3.8M
- 2024Hurricane Helene584 households applied for aid$468K aid approved
- 2024Hurricane Debby46 households applied for aid$53K aid approved
- 2023Hurricane Idalia55 households applied for aid$13K aid approved
- 2022Hurricane Ian1,012 households applied for aid$691K aid approved
- 2017Hurricane Irma1,542 households applied for aid$631K aid approved2 flood claims paid for it, $31K
Show all 9
- 2016Hurricane Hermine1 households applied for aid$5K aid approved
- 2004Hurricane Jeanne171 households applied for aid$298K aid approved
- 2004Hurricane Frances98 households applied for aid$137K aid approved3 flood claims paid for it, $51K
Hillsborough County has had 34 natural disasters declared by the President since 1953, most often hurricanes and tropical storms, then severe storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Also 3 FEMA wildfire suppression grants (Fire Management Assistance, not a disaster declaration) for fires in Hillsborough County, 1999–2001.
Old photos of Thonotosassa after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Thonotosassa archive →Thonotosassa and its neighbors
Thonotosassa is 3rd of the 3 graded towns here, from least expected damage per building to most. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Mango | C+more damage than 60% | hurricanes | 4 |
| East Lake-Orient Park | Cmore damage than 68% | hurricanes | 22 |
| Thonotosassa | Cmore damage than 74% | river and rain flooding | 51 |
Hazard risk = FEMA’s expected yearly building damage per dollar of building value, vs. the 21,298 U.S. towns we grade; the map is shaded by fifths of the same scale. Flood claims = paid federal flood insurance claims on record.
Get ready for what Thonotosassa faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- The season runs June through November and peaks from mid-August to mid-October.
- Bring in porch furniture and anything the wind can throw.
- Fill the gas tank and charge phones before the storm arrives.
- Pick your spot now: the lowest floor, an inside room, no windows.
- A watch means be ready; a warning means take cover now.
- Keep shoes and a flashlight by the bed.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in Thonotosassa
Is Thonotosassa at risk for natural disasters?
On FEMA’s National Risk Index, Thonotosassa has higher expected damage per building than 74% of U.S. towns: C for hazard risk, #247 of 638 in Florida. Most of the expected damage is river and rain flooding (45%) and hurricanes (44%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Thonotosassa flood?
Flood insurance has paid 51 claims in Thonotosassa since 1988, $4.0M in all, or 8.5 per 1,000 homes, more than 71% of U.S. towns with a flood insurance record. The most claims came from Hurricane Milton (32).
Is Thonotosassa in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Hillsborough County, 61% of homes in mapped flood zones carry federal flood insurance, and 12.1% of all homes do.
How much is flood insurance in Thonotosassa?
FEMA’s Community Rating System list shows no discount for Thonotosassa’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in Thonotosassa?
By FEMA money that reached Thonotosassa, Hurricane Milton (2024): 2,702 households applied for aid, $2.6M approved. By flood claims, Hurricane Milton: 32 paid, $3.8M.
Is Thonotosassa at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (45%), and Thonotosassa’s rate for it is lower than 54% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Thonotosassa.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Thonotosassa’s residents lived in the 2020 census; 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. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.