Bronx County, New York Natural Disaster Risk
FEMA National Risk Index assessment · NY
HighComposite Risk Score
National percentile: 98th
Bronx County faces high composite natural disaster risk (NRI Risk Index score 98.3, 98th national percentile), driven primarily by cold wave and heat wave exposure. Expected annual loss across all 18 hazard types is $212M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Bronx County is high, with a National Risk Index score of 98.3 out of 100 — placing it in the 98th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
The county's risk is driven primarily by cold wave (prolonged spells of dangerously low temperatures) at Very High risk — $31M in expected annual loss and about 0.55 events per year; heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at High risk — $39M in expected annual loss and about 11.26 events per year; and strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at Very High risk — $6M in expected annual loss and about 5.39 events per year. Across all hazards, FEMA estimates $212M in expected annual loss for a population of 1.47M.
Beyond physical exposure, Bronx County has a very high social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
The federal record bears this out: Bronx County has received 20 federal disaster declarations since 1971, including 8 for hurricane events and 3 for snowstorm events. The most recent was Remnants of Hurricane Ida (hurricane), declared in September 2021.
Among 62 New York counties, Bronx County ranks #4 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | Very High | 0.55 / yr | $31M |
| Heat Wave | High | 11.26 / yr | $39M |
| Strong Wind | Very High | 5.39 / yr | $6M |
| Winter Weather | Very High | 10.49 / yr | $1M |
| Riverine Flood | High | 2.04 / yr | $100M |
| Earthquake | Medium | 0.00 / yr | $14M |
| Hurricane | High | 0.16 / yr | $13M |
| Lightning | High | 31.31 / yr | $999K |
| Hail | Medium | 1.89 / yr | $829K |
| Ice Storm | High | 0.74 / yr | $385K |
| Coastal Flood | High | 5.95 / yr | $2M |
| Tornado | Medium | 0.02 / yr | $3M |
| Landslide | Very Low | 0.01 / yr | $500 |
| Wildfire | Very Low | 0.00 / yr | $498 |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Drought | Very Low | 0.83 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Bronx County has received 20 federal disaster declarations since 1971, most recently Remnants of Hurricane Ida in September 2021. Most frequent causes: Hurricane (8), Snowstorm (3), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| September 2021 | Hurricane | Remnants of Hurricane Ida |
| September 2021 | Hurricane | Remnants of Hurricane Ida |
| August 2021 | Hurricane | Hurricane Henri |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| October 2012 | Hurricane | Hurricane Sandy |
| October 2012 | Hurricane | Hurricane Sandy |
| August 2011 | Hurricane | Hurricane Irene |
| August 2011 | Hurricane | Hurricane Irene |
| February 2011 | Severe Storm | Severe Winter Storm and Snowstorm |
Showing the 10 most recent of 20 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Bronx County?
Bronx County has a composite FEMA National Risk Index score of 98.3 out of 100, placing it in the High category and the 98th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Bronx County?
The three highest-rated hazards are Cold Wave (Very High, $31M EAL), Heat Wave (High, $39M EAL), Strong Wind (Very High, $6M EAL). These account for most of the county's expected annual losses.
How does Bronx County compare to other New York counties?
Bronx County ranks #4 of 62 New York counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Bronx County had?
FEMA records 20 federal disaster declarations for Bronx County since 1971, most often 8 for hurricane events and 3 for snowstorm events. The most recent was Remnants of Hurricane Ida, declared in September 2021.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Bronx County's $212M EAL is a statistical average, not a guarantee for any specific year or address.