Cos Cob’s biggest natural hazard is inland flooding
Most of the natural-hazard damage FEMA expects in Cos Cob comes from inland flooding, and overall the risk is high for a U.S. community.
What stands out about Cos Cob’s weather risks
Read from FEMA’s records below. The page puts what stands out first.
Does Cos Cob flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Cos Cob. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Cos Cob isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: the county.How exposed is Cos Cob?
FEMA expects yearly storm and flood damage to homes and buildings here to be higher than in 69% of U.S. communities, mostly from inland flooding.
Rated higher than 146 of the 177 Connecticut towns we cover.
Cos Cob covers 2 census tracts, combined by population.
What Cos Cob faces
Each hazard’s share of the damage FEMA expects here, and how it compares with the rest of the country.
Inland flooding
Hurricanes
Get ready for what Cos Cob actually faces
A short kit for its top hazards, 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.
- Keep a shovel, a blanket and snacks in the car.
- Clear snow from furnace and dryer vents.
- Check on older neighbors when the power goes out.
- 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 Cos Cob’s own flood-insurance community; household aid to the registrant’s city; repair grants to Cos Cob.
- 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. Across Cos Cob, expected losses total about $4.5M a year, counting buildings, people and crops.
Storm stories
Memories, warnings and help from neighbors in Cos Cob.
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. Weather alerts: National Weather Service. Preparedness tips: Ready.gov. An average of past damage, not a forecast.