Photo: DanTD · CC BY-SA 3.0On FEMA’s figures, Islip faces less hazard damage per building than 92% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Islip gets an A for hazard risk: lower expected damage per building than 92% of U.S. towns, #145 of 758 in New York. Most of that expected damage is river and rain flooding (64%), then hurricanes (14%). Flood insurance has paid 4,791 claims here since 1978.
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 stands out about Islip’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Islip 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
Coastal flooding
Earthquakes
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 Islip’s grade
River and rain flooding is 64% of the building damage FEMA expects in Islip, and Islip’s rate of river and rain flooding damage is lower than 82% of U.S. census tracts. Coastal flooding adds 13%, at a rate in the top 4% of U.S. census tracts.
A #145 of 758 in New York; lower expected damage per building than 92% of U.S. towns (21,298).
Islip’s residents live in 81 census tracts; FEMA’s figures are combined by where they live.
The typical New York town has lower expected damage than 69% of U.S. towns; within the state, Islip has less expected damage per building than 81% of New York towns.
Among the 400 U.S. cities of 100,000 or more, Islip has lower expected damage per building than 97% (#14 of 400). Because it is so big, its total expected yearly loss, $61.4M, is the 199th largest of those 400.
Does Islip flood? Yes: 4,791 flood claims since 1978
Every paid claim on a federal flood insurance policy in Islip, from FEMA’s records: 43.7 per 1,000 homes, more than 92% of the 13,809 U.S. towns with a flood insurance record.
- Hurricane Sandy2,503 claims · $181M
- The “Halloween” storm299 claims · $3.4M
- The December Storm - nor’easter263 claims · $7.2M
Islip isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Suffolk County.12 federal disasters brought FEMA money to Islip
Disasters that paid out in Islip itself (aid to households or repair grants to the Town of Islip), newest first, with that year’s flood claims.
- 2022Severe Winter Storm and Snowstorm$57K to the Town of Islip for repairs1 flood claim paid that year
- 2021Remnants of Hurricane Ida62 households applied for aid$4K aid approved8 flood claims paid that year
- 2020Tropical Storm Isaias$4.2M to the Town of Islip for repairs3 flood claims paid that year
- 2017Severe Winter Storm and Snowstorm$3K to the Town of Islip for repairs17 flood claims paid that year
- 2013Severe Winter Storm and Snowstorm$907K to the Town of Islip for repairs5 flood claims paid that year
- 2012Hurricane Sandy300 households applied for aid$1.1M aid approved$18.9M to the Town of Islip for repairs2,503 flood claims paid for it, $181M
Show all 12
- 2011Hurricane Irene14 households applied for aid$10K aid approved$1.8M to the Town of Islip for repairs236 flood claims paid for it, $6.0M
- 2010Severe Winter Storm and Snowstorm$1.4M to the Town of Islip for repairs
- 2010Severe Storms and Flooding$531K to the Town of Islip for repairs
- 2009Severe Storms and Flooding Assoc W Td Ida and Nor’easter$1.6M to the Town of Islip for repairs9 flood claims paid that year
- 2007Severe Storms and Inland and Coastal Flooding$2.0M to the Town of Islip for repairs16 flood claims paid that year
- 2003Snow$612K to the Town of Islip for repairs9 flood claims paid that year
Suffolk County has had 26 natural disasters declared by the President since 1953, most often severe storms, then hurricanes and tropical storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees; the 2001 World Trade Center declarations.
Old photos of Islip after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Islip archive →Islip and its neighbors
Islip is 2nd of the 5 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 |
|---|---|---|---|
| Smithtown | A+less damage than 98% | river and rain flooding | 225 |
| Islip | Aless damage than 92% | river and rain flooding | 4,791 |
| Brookhaven | A−less damage than 80% | river and rain flooding | 3,825 |
| Babylon | B+less damage than 71% | river and rain flooding | 4,003 |
| Babylon | Bless damage than 62% | river and rain flooding | 1,645 |
| West Islip | — | a Census area inside a town; graded with the town | |
| Bayport | — | a Census area inside a town; graded with the town | |
| Great River | — | a Census area inside a town; graded with the town | |
| West Sayville | — | a Census area inside a town; graded with the town | |
| Ronkonkoma | — | a Census area inside a town; graded with the town | |
| Lake Ronkonkoma | — | a Census area inside a town; graded with the town | |
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 Islip 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.
- Know your evacuation zone and the way off the coast.
- Storm surge comes fast: leave when you’re told, not when the water arrives.
- Move cars to high ground before king tides and nor’easters.
- 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.
Questions about natural hazards in Islip
Is Islip at risk for natural disasters?
On FEMA’s National Risk Index, Islip has lower expected damage per building than 92% of U.S. towns: A for hazard risk, #145 of 758 in New York. Most of the expected damage is river and rain flooding (64%) and hurricanes (14%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Islip flood?
Flood insurance has paid 4,791 claims in Islip since 1978, $221M in all, or 43.7 per 1,000 homes, more than 92% of U.S. towns with a flood insurance record. 547 properties have flooded more than once. The most claims came from Hurricane Sandy (2,503).
Is Islip 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 Suffolk County, 66% of homes in mapped flood zones carry federal flood insurance, and 5.4% of all homes do.
How much is flood insurance in Islip?
FEMA’s Community Rating System list shows no discount for Islip’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 Islip?
By FEMA money that reached Islip, Hurricane Sandy (2012): 300 households applied for aid, $1.1M approved, and $18.9M to the Town of Islip for repairs. By flood claims, Hurricane Sandy: 2,503 paid, $181M.
Is Islip at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (64%), and Islip’s rate for it is lower than 82% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Islip.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Islip’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.