Lewisville’s biggest natural hazard is cold waves
Most of the natural-hazard damage FEMA expects in Lewisville comes from cold waves, and overall the risk is moderate for a U.S. community.
What stands out about Lewisville’s weather risks
Read from FEMA’s records below. The page puts what stands out first.
What Lewisville faces
Each hazard’s share of the damage FEMA expects here, and how it compares with the rest of the country.
Cold waves
Inland flooding
Earthquakes
Heat waves
Does Lewisville flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Lewisville. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Lewisville isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Jefferson County.How exposed is Lewisville?
FEMA expects yearly storm and flood damage to homes and buildings here to be higher than in 44% of U.S. communities, mostly from cold waves and inland flooding.
Calmer than 180 of the 234 Idaho towns we cover.
Lewisville is smaller than a census tract, so it shares the figures of the tract around its center.
Federal disasters declared here
None of the disasters declared for Jefferson County shows FEMA aid or repair money reaching Lewisville itself in FEMA’s records.
Jefferson County has had 4 natural disasters declared since 1953, most often floods and hurricanes.
Get ready for what Lewisville actually faces
A short kit for its top hazards, what to check before you buy, and where neighbors get alerts.
- Let faucets drip so pipes don’t freeze.
- Know where your water shutoff is.
- Never heat the house with the oven or a grill.
- 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.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- 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.
What these numbers can and can’t tell you
- An average, not a forecast. FEMA’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 there, so a big city isn’t rated riskier just for having more buildings.
- Money that reached town. Flood claims are matched to Lewisville’s own flood-insurance community; household aid to the registrant’s city; repair grants to the City of Lewisville.
- It follows property value. FEMA’s model weighs damage to buildings, so a place that recently lost many homes can rate lower than it feels.
Storm stories
Memories, warnings and help from neighbors in Lewisville.
Your answer becomes a post in Town Square.
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. Preparedness tips: Ready.gov. An average of past damage, not a forecast.