Massachusetts ice storm risk
Middlesex County has the highest ice storm risk in Massachusetts, scoring 99.7 out of 100 — rated "Very High" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Middlesex County | 99.7 | Very High |
| 2 | Worcester County | 98.6 | Very High |
| 3 | Essex County | 97.4 | Very High |
| 4 | Hampden County | 94.6 | Relatively High |
| 5 | Norfolk County | 89.7 | Relatively High |
| 6 | Bristol County | 83.2 | Relatively High |
| 7 | Plymouth County | 83.1 | Relatively High |
| 8 | Suffolk County | 79.9 | Relatively Moderate |
| 9 | Hampshire County | 79.1 | Relatively Moderate |
| 10 | Franklin County | 77.7 | Relatively Moderate |
| 11 | Berkshire County | 75.3 | Relatively Moderate |
| 12 | Barnstable County | 46.3 | Relatively Low |
| 13 | Dukes County | 11.5 | Very Low |
| 14 | Nantucket County | 0.1 | Very Low |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Ice Storm risk nationally:
Other hazard risks in Massachusetts:
Frequently asked questions
What is the highest ice storm risk county in Massachusetts?
Middlesex County, MA has the highest ice storm risk in Massachusetts, with a FEMA National Risk Index score of 99.7 out of 100 (rated "Very High").
How many counties in Massachusetts are rated Very High for ice storm risk?
3 of 14 scored Massachusetts counties are rated "Very High" for ice storm risk by FEMA's National Risk Index.
What causes ice storm risk in Massachusetts?
Ice storm risk covers damaging freezing rain and sleet accumulation, which collapses power lines, trees, and structures. The highest-risk counties cluster in a band from eastern Texas and Arkansas through the Carolinas and New England, where warm Gulf moisture overruns cold arctic air most frequently. Ice storms cause catastrophic and long-lasting power outages. Ice storm and sleet events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.