Summary
Plan status as of 2026-09-30: No county-level plan row in FEMA data.
Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($59,518,167 a year), Hurricane ($12,923,252) and Earthquake ($11,650,421).
The tables that follow are organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B (B1-a to B2-c); each heading says which item its tables support.
Plan clock
No county-level plan row in FEMA data
What changed since your last plan
Not available. No county-level plan row in FEMA data, so there is no approval date to count from.
Sources: 1, 2, 4, 6 (numbered list at the end)
Plan status for every jurisdiction listed in this county
Source: 1
| Jurisdiction | Type | Status | Plan | Approved | Expires | Days to expirynegative = days since expiry |
|---|---|---|---|---|---|---|
| Boston city | City | Approved, expires 2026-12-05 | City of Boston 2021 Natural Hazard Mitigation Plan Update (FEMA plan 107823) | 2021-12-06 | 2026-12-05 | 66 |
| Chelsea city | City | Approved, expires 2027-07-11 | Chelsea, MA 2022 Hazard Mitigation Plan (FEMA plan 108264) | 2022-07-12 | 2027-07-11 | 284 |
| Revere city | City | Approved, expires 2027-02-16 | The City of Revere, Massachusetts Hazard Mitigation Plan - 2021 Update (FEMA plan 107869) | 2022-02-17 | 2027-02-16 | 139 |
| Winthrop Town city | City | Approved, expires 2031-08-13 | Town of Winthrop Hazard Mitigation Plan 2025 Update (FEMA plan 111531) | 2026-08-14 | 2031-08-13 | 1,778 |
| Name not given in FEMA data (ID NM01_12383) | College/University | Expired on 2021-05-12 | University of Massachusetts Multi-Campus Hazard Mitigation Plan (FEMA plan 12383) | 2016-05-12 | 2021-05-12 | -1,967 |
State plan status and tribal plans in this state: see the state page.
Supports FEMA checklist item B1-a: hazard identification
Hazards NRI does not cover (local data needed)
- dam failure (incl. upstream dams)
- levee failure
- flash flood as its own subtype
- ice jams
- debris flows
- erosion (riverine and coastal)
- land subsidence and sinkholes
- expansive soils
The 18 National Risk Index hazards, ranked by expected annual loss (EAL)
Sources: 5, 6
| Rank by EAL | Hazard | NRI risk rating | EAL rating | EAL buildingsmodeled dollars per year | EAL agriculturemodeled dollars per year | Cost of expected deaths and injuriesFEMA's dollar value per year, not property damage | EAL total (see note)modeled dollars per year | Storm Events records, 1996 to 2026-06-30count | Storm Events coverage note |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Inland Flooding | Relatively High | Relatively High | $59,469,894 | $313 | $47,960 | $59,518,167 | 72 | |
| 2 | Hurricane | Relatively High | Relatively High | $12,415,981 | $5,559 | $501,711 | $12,923,252 | 4 | |
| 3 | Earthquake | Relatively Moderate | Relatively Moderate | $8,238,651 | n/a | $3,411,770 | $11,650,421 | Storm Events does not record earthquakes. | |
| 4 | Heat Wave | Relatively High | Relatively High | $30 | $82 | $9,433,664 | $9,433,776 | 21 | |
| 5 | Cold Wave | Relatively High | Relatively High | $677 | $64 | $8,677,694 | $8,678,435 | 8 | |
| 6 | Coastal Flooding | Relatively High | Relatively High | $5,228,356 | n/a | $1,059,907 | $6,288,266 | 50 | |
| 7 | Tornado | Relatively Moderate | Relatively Moderate | $2,217,516 | $5 | $378,485 | $2,596,006 | 1 | |
| 8 | Lightning | Very High | Relatively High | $409,876 | n/a | $1,908,214 | $2,318,090 | 19 | |
| 9 | Hail | Relatively Moderate | Relatively Low | $598,469 | $2 | $16,652 | $615,123 | 20 | |
| 10 | Strong Wind | Relatively Moderate | Relatively Low | $224,347 | under $1 | $255,897 | $480,245 | 277 | Includes 76 High Wind and 100 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition). |
| 11 | Ice Storm | Relatively Moderate | Relatively Moderate | $129,801 | n/a | $199,097 | $328,898 | 0 | No recorded events in Storm Events since 1996 (data through 2026-06-30). |
| 12 | Winter Weather | Relatively Low | Relatively Low | $26,709 | under $1 | $16,678 | $43,387 | 99 | |
| 13 | Wildfire | Very Low | Very Low | $2,076 | under $1 | $290 | $2,366 | 0 | No recorded events in Storm Events since 1996 (data through 2026-06-30). |
| 14 | Landslide | Very Low | Very Low | $367 | n/a | $39 | $406 | 0 | No recorded events in Storm Events since 1996 (data through 2026-06-30). |
| 15 | Drought | No Rating | No Expected Annual Losses | n/a | $0 | n/a | $0 | 11 | |
| Tsunami | Insufficient Data | Insufficient Data | n/a | n/a | n/a | n/a | 0 | No recorded events in Storm Events since 1996 (data through 2026-06-30). |
Total = buildings + agriculture + population equivalence; FEMA values each expected death (or 10 injuries) at $13.7 million (2024 dollars).
NRI risk rating combines expected annual loss with social vulnerability and community resilience; EAL rating rates expected annual loss alone. Both compare this county with all U.S. counties.
Local data needed: state and local wildfire, landslide and tsunami records (Storm Events records these hazards only in part).
Not applicable to this county per NRI, with no federal declaration and no Storm Events record since 1996: avalanche and volcanic activity. That is the evidence for leaving them out of the plan.
The state hazard mitigation plan also lists hazards for this county; FEMA asks the plan to explain any hazard it leaves out.
Supports FEMA checklist item B1-b: hazard location
Affects the whole county (national data give no location within it): Cold Wave, Drought, Hail, Heat Wave, Ice Storm, Lightning, Strong Wind and Winter Weather.
Coastal Flooding and Inland Flooding: The FEMA Flood Insurance Rate Map (FIRM) is the required location source for flooding. See the FEMA Flood Map Service Center (https://msc.fema.gov) for this county.
Hazards that vary within the county: highest-rated census tracts
Source: 5
| Hazard | Highest-rated census tractsNRI risk rating, score 0 to 100 |
|---|---|
| Earthquake | tract 104.05 (Relatively Moderate, 86.3); tract 103 (Relatively Moderate, 85.1); tract 810.01 (Relatively Moderate, 83.5) |
| Hurricane | tract 104.05 (Relatively High, 90.2); tract 701.04 (Relatively Moderate, 88.5); tract 103 (Relatively Moderate, 85.2) |
| Landslide | tract 1201.05 (Very Low, 74.5); tract 1606.01 (Very Low, 73.2); tract 1701.01 (Very Low, 72.3) |
| Tornado | tract 104.05 (Relatively Moderate, 57.4); tract 701.04 (Relatively Low, 52.5); tract 103 (Relatively Low, 44.9) |
| Tsunami | no tract has a National Risk Index rating for this hazard |
| Wildfire | tract 1703.02 (Very Low, 61.7); tract 1106.01 (Very Low, 54.9); tract 106 (Very Low, 52.9) |
Up to 3 census tracts per hazard, highest National Risk Index rating first, then highest score; a tract number is the Census tract number (for example 104.05 is Census Tract 104.05). FEMA's Resilience Analysis and Planning Tool maps the National Risk Index for every tract: https://www.fema.gov/emergency-managers/practitioners/resilience-analysis-and-planning-tool
Supports FEMA checklist item B1-c: hazard extent
Extent: scale, observed range and worst recorded event per hazard
Sources: 6, 7
| Hazard | Scale | Recordscount and years | Observed range | Worst recorded event | Most damaging (when different) | How it applies to jurisdictions | Note |
|---|---|---|---|---|---|---|---|
| Coastal Flood, Storm Surge/Tide | none in data (flood depth: FIRM) | 50 records, 2002 to 2024 (49 zone-level) | Coastal Flood, 2012-10-29, $3,000,000 property; $0 crops (2012 dollars); NWS zone MAZ015 | Event records naming jurisdictions in the plan: Revere city (1 record). Zone-level records (49) apply countywide. | Flood depth: see the FEMA Flood Insurance Rate Map. | ||
| Cold/Wind Chill, Extreme Cold/Wind Chill | wind chill | 8 records, 1999 to 2018 (8 zone-level) | 1 day to 2 days (median 1 day); 6 with a recorded value | 2 consecutive days, 2007-02-03 to 2007-02-04, 1 direct death, zone-level | Countywide (zone-level records). | Cold/Wind Chill records from May to September (a frost night, not a cold wave) are counted but not used for the longest run. | |
| Frost/Freeze (outside NRI's Cold Wave definition) | crop damage | 0 | |||||
| Drought | U.S. Drought Monitor scale (D0 to D4) | 11 records, 1999 to 2017 (11 zone-level) | 1 day to 183 days (median 17.5 days); 4 with a recorded value | 183 days (about 6.0 months), 2016-07-26 to 2017-01-24, a run of 7 consecutive Storm Events drought records, zone-level | Countywide (zone-level records). | Storm Events enters a drought at D2 or worse east of the Rockies and D3 or worse from the Rockies west (NWS Instruction 10-1605); NRI drought counts D3 and D4 only. | |
| Earthquake | Modified Mercalli (local data) | 0 | Storm Events does not record earthquakes; the USGS earthquake catalog is the source. | ||||
| Hail | hail size (inches) | 24 records, 1966 to 2020 | 0.75 in to 2 in (median 0.75 in); 24 with a recorded value | 2 in hail, 2015-08-04 | Event records naming jurisdictions in the plan: Revere city (3 records), Boston city (2 records). | ||
| Excessive Heat, Heat | heat index (in event narratives) | 21 records, 1996 to 2018 (21 zone-level) | 1 day to 2 days (median 1 day); 10 with a recorded value | 2 consecutive days, 2001-05-03 to 2001-05-04, zone-level | Countywide (zone-level records). | Heat records from November to March (unseasonable warmth, not a heat wave) are counted but not used for the longest run. | |
| Hurricane, Tropical Storm, Tropical Depression | Saffir-Simpson | 4 records, 2011 to 2021 (4 zone-level) | Strongest recorded: Tropical Storm record, 2011-08-28, $3,450,000 property; $0 crops (2011 dollars); NWS zone MAZ015 | Countywide (zone-level records). | Storm Events files every zone of a storm's episode under the storm's type; flooding from the storm is filed as Flood or Flash Flood records. | ||
| Ice Storm | Sperry-Piltz ice scale (local data) | 0 | |||||
| Flash Flood, Flood, Lakeshore Flood | damage and flood days (flood depth: FIRM) | 72 records, 1996 to 2024 (1 zone-level) | Flood, 2001-03-05, $15,000,000 property; crops not reported (2001 dollars); NWS zone MAZ015 | Event records naming jurisdictions in the plan: Boston city (14 records), Revere city (14 records), Chelsea city (8 records). Zone-level records (1) apply countywide. | Flood depth: see the FEMA Flood Insurance Rate Map. Storm Events damage is often $0 or blank for floods, major ones included; FEMA Public Assistance by declaration (B1-d) shows which floods cost the most. | ||
| Debris Flow | none (count and damage only) | 0 | |||||
| Lightning | annualized frequency (the measure FEMA's Local Mitigation Planning Handbook names) | 19 records, 1997 to 2023 | Lightning, 2010-08-05, $0 property; $0 crops (2010 dollars), 1 direct death | Lightning, 2008-06-27, $5,000,000 property; $0 crops (2008 dollars) | Event records naming jurisdictions in the plan: Boston city (5 records), Revere city (2 records). | Storm Events lists lightning with damage or casualties. | |
| High Wind and Strong Wind (outside NRI's Strong Wind definition) | wind speed (kt and mph) | 176 records, 1996 to 2025 (176 zone-level) | 27 kt (31 mph) to 68 kt (78 mph) (median 45 kt (52 mph)); 128 with a recorded value | 68 kt (78 mph) measured gust, High Wind, 2006-01-18; NWS zone MAZ015 | High Wind, 2012-10-29, $3,000,000 property; $0 crops (zone total, 2012 dollars) | Countywide (zone-level records). | |
| Thunderstorm Wind | wind speed (kt and mph) | 130 records, 1956 to 2025 | 45 kt (52 mph) to 73 kt (84 mph) (median 50 kt (58 mph)); 115 with a recorded value | 73 kt (84 mph), measurement type not recorded, Thunderstorm Wind, 1956-06-13 | Thunderstorm Wind, 2010-06-06, $100,000 property; $0 crops (2010 dollars) | Event records naming jurisdictions in the plan: Boston city (31 records), Revere city (10 records), Chelsea city (3 records). | |
| Tornado | Enhanced Fujita (Fujita before Feb 2007) | 1 record, 2014 | F/EF2; 1 with a recorded value | EF2 tornado, 2014-07-28, 1.93 mi within this county, 660 yd wide, $4,000,000 property; $0 crops (2014 dollars), 2 direct injuries | Event records naming jurisdictions in the plan: Chelsea city (1 record), Revere city (1 record). | Before 1996 a tornado is listed once, under the county where it began, with its whole path's rating and length; from 1996 on, each county lists its own segment. Length is not used to rank tornadoes (see Methods). | |
| Tsunami | none (count and damage only) | 0 | |||||
| Wildfire | acres burned (local data) | 0 | |||||
| Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet | none in data (snowfall: local data) | 99 records, 1996 to 2026 (99 zone-level) | Heavy Snow, 1996-01-07, $7,000,000 property; crops not reported (1996 dollars); NWS zone MAZ015 | Countywide (zone-level records). |
In event narratives only (local data needed): wind chill, temperature, heat index, ice thickness, acres burned and snow depth; any physical measure of debris flow, lightning and tsunami.
Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records from zones that no NWS zone-county file places in this county (mostly before 2020) are not counted here (the Methods page explains the zone matching).
Dollars are nominal (as reported), labeled with the year; not adjusted for inflation.
Supports FEMA checklist item B1-d: previous occurrences
Federal declarations for this county: 38 declarations covering 28 separate hazard incidents counted in this packet (declarations for the same incident count once; non-natural and evacuation-only declarations are not counted).
No county-level plan row in FEMA data, so there is no approval date to count from.
Federal disaster declarations for this county
Sources: 1, 2, 3
| Declared | Incident began | FEMA number | Type | Title | Mapped hazard | County Public Assistancefederal share obligated, nominal dollars | Flags | Notes |
|---|---|---|---|---|---|---|---|---|
| 2023-09-15 | 2023-09-15 | EM-3599-MA | Emergency | Hurricane Lee | Hurricane | $173,126.76 | within last 5 years | |
| 2022-04-18 | 2022-01-28 | DR-4651-MA | Major disaster | Severe Winter Storm and Snowstorm | Winter Weather | $9,862,630.59 | within last 5 years | |
| 2020-03-27 | 2020-01-20 | DR-4496-MA | Major disaster | COVID-19 Pandemic | Non-natural, not counted | $491,517,173.77 | ||
| 2020-03-13 | 2020-01-20 | EM-3438-MA | Emergency | COVID-19 | Non-natural, not counted | no Public Assistance recorded | same incident as DR-4496 | |
| 2018-07-19 | 2018-03-13 | DR-4379-MA | Major disaster | Severe Winter Storm and Snowstorm | Winter Weather | $12,192,682.41 | ||
| 2015-04-13 | 2015-01-26 | DR-4214-MA | Major disaster | Severe Winter Storm, Snowstorm, and Flooding | Inland Flooding; Winter Weather | $25,562,137.63 | ||
| 2013-04-19 | 2013-02-08 | DR-4110-MA | Major disaster | Severe Winter Storm, Snowstorm, and Flooding | Inland Flooding; Winter Weather | $3,861,484.42 | ||
| 2013-04-17 | 2013-04-15 | EM-3362-MA | Emergency | Explosions | Non-natural, not counted | $3,591,762.10 | ||
| 2012-12-19 | 2012-10-27 | DR-4097-MA | Major disaster | Hurricane Sandy | Hurricane | $3,749,961.97 | ||
| 2012-10-28 | 2012-10-27 | EM-3350-MA | Emergency | Hurricane Sandy | Hurricane | no Public Assistance recorded | same incident as DR-4097 | |
| 2011-08-26 | 2011-08-26 | EM-3330-MA | Emergency | Hurricane Irene | Hurricane | $916,866.43 | ||
| 2011-03-07 | 2011-01-11 | DR-1959-MA | Major disaster | Severe Winter Storm and Snowstorm | Winter Weather | $9,430,940.63 | ||
| 2010-09-02 | 2010-09-01 | EM-3315-MA | Emergency | Hurricane Earl | Hurricane | $63,420.86 | ||
| 2010-05-03 | 2010-05-01 | EM-3312-MA | Emergency | Water Main Break | Non-natural, not counted | no Public Assistance recorded | ||
| 2010-03-29 | 2010-03-12 | DR-1895-MA | Major disaster | Severe Storms and Flooding | Inland Flooding | $4,466,860.58 | ||
| 2008-12-13 | 2008-12-11 | EM-3296-MA | Emergency | Severe Winter Storm | Winter Weather | no Public Assistance recorded | ||
| 2006-05-25 | 2006-05-12 | DR-1642-MA | Major disaster | Severe Storms and Flooding | Inland Flooding | $654,853.84 | FEMA's declaration record does not list Public Assistance, but FEMA's PA project summaries show obligations for this county | |
| 2005-11-10 | 2005-10-07 | DR-1614-MA | Major disaster | Severe Storms and Flooding | Inland Flooding: designated for Hazard Mitigation only (no Public or Individual Assistance for this county); not counted | $809,896.39 | FEMA's declaration record does not list Public Assistance, but FEMA's PA project summaries show obligations for this county | |
| 2005-09-13 | 2005-08-29 | EM-3252-MA | Emergency | Hurricane Katrina Evacuation | Hurricane: evacuation support, not a local hazard event; not counted | no Public Assistance recorded | ||
| 2005-02-17 | 2005-01-22 | EM-3201-MA | Emergency | Record and/or Near Record Snow | Winter Weather | $15,673,117.74 | ||
| 2004-04-21 | 2004-04-01 | DR-1512-MA | Major disaster | Flooding | Inland Flooding | PA not declared for this county | ||
| 2004-01-15 | 2003-12-06 | EM-3191-MA | Emergency | Snow | Winter Weather | $3,267,208.62 | ||
| 2003-03-11 | 2003-02-17 | EM-3175-MA | Emergency | Snow | Winter Weather | $9,724,128.12 | ||
| 2001-04-10 | 2001-03-05 | DR-1364-MA | Major disaster | Severe Storms and Flooding | Inland Flooding | PA not declared for this county | ||
| 1998-06-23 | 1998-06-13 | DR-1224-MA | Major disaster | Heavy Rains and Flooding | Inland Flooding | PA not declared for this county | ||
| 1996-10-25 | 1996-10-20 | DR-1142-MA | Major disaster | Extreme Weather Conditons and Flooding | Inland Flooding | no Public Assistance recorded | ||
| 1996-10-23 | 1996-10-20 | EM-3119-MA | Emergency | Extreme Weather Conditions and Flooding | Inland Flooding | no Public Assistance recorded | same incident as DR-1142 | |
| 1996-01-24 | 1996-01-07 | DR-1090-MA | Major disaster | Blizzard of 96 | Winter Weather | no Public Assistance recorded | ||
| 1993-03-16 | 1993-03-13 | EM-3103-MA | Emergency | Blizzards, High Winds & Record Snowfall | Winter Weather | no Public Assistance recorded | ||
| 1992-12-21 | 1992-12-11 | DR-975-MA | Major disaster | Winter Coastal Storm | Coastal Flooding | no Public Assistance recorded | ||
| 1991-11-04 | 1991-10-30 | DR-920-MA | Major disaster | Coastal Storm | Coastal Flooding | no Public Assistance recorded | ||
| 1991-08-26 | 1991-08-19 | DR-914-MA | Major disaster | Hurricane Bob | Hurricane | no Public Assistance recorded | ||
| 1985-10-28 | 1985-09-27 | DR-751-MA | Major disaster | Hurricane Gloria | Hurricane | no Public Assistance recorded | ||
| 1978-02-10 | 1978-02-06 | DR-546-MA | Major disaster | Coastal Storms, Flood, Ice & Snow | Coastal Flooding | no Public Assistance recorded | ||
| 1978-02-07 | 1978-02-07 | EM-3059-MA | Emergency | Blizzard & Snowstorms | Winter Weather | no Public Assistance recorded | ||
| 1973-10-16 | 1973-10-16 | DR-405-MA | Major disaster | Fire (City of Chelsea) | Non-natural, not counted | no Public Assistance recorded | ||
| 1972-09-28 | 1972-09-28 | DR-357-MA | Major disaster | Toxic Algae in Coastal Waters | Fishing Losses: economic loss, not a physical hazard event; non-natural, not counted | PA not declared for this county | ||
| 1972-03-06 | 1972-03-06 | DR-325-MA | Major disaster | Severe Storms & Flooding | Inland Flooding | no Public Assistance recorded |
County Public Assistance: applicants the FEMA record places in this county, including any state agencies FEMA files there; statewide rows are listed on the state page; federal share obligated, nominal dollars.
Statewide declarations
Source: 2
| Declared | Incident began | FEMA number | Type | Title | Mapped hazard |
|---|---|---|---|---|---|
| 1955-08-20 | 1955-08-20 | DR-43-MA | Major disaster | Hurricane & Floods | Hurricane (primary); also designated: Inland Flooding |
| 1954-09-02 | 1954-09-02 | DR-22-MA | Major disaster | Hurricanes | Hurricane (primary); also designated: Inland Flooding |
| 1953-06-11 | 1953-06-11 | DR-7-MA | Major disaster | Tornado | Tornado |
FEMA recorded these with designated area Statewide and no county, so they are listed on every county page in the state and not counted with county rows. Local data needed: whether each one affected this county.
1 Fire Management declaration (1995-09-12 to 1995-09-12) FEMA filed as Statewide with no county; each names one local fire. Listed on the state page.
Public Assistance filed under this county for declarations that do not list it: 23 rows, $18,874,379.97
Sources: 2, 3
| FEMA number | Declared | Title | Applicant | PA obligatedfederal share obligated, nominal dollars |
|---|---|---|---|---|
| DR-4372-MA | 2018-06-25 | Severe Winter Storm and Flooding | Massachusetts Water Resources Authority | $13,042.25 |
| DR-4372-MA | 2018-06-25 | Severe Winter Storm and Flooding | Massachusetts Environmental Police | $14,917.12 |
| DR-4372-MA | 2018-06-25 | Severe Winter Storm and Flooding | Conservation and Recreation, Department of | $406,195.44 |
| DR-4051-MA | 2012-01-06 | Severe Storm and Snowstorm | Massachusetts Water Resources Authority | $169,101.82 |
| DR-4051-MA | 2012-01-06 | Severe Storm and Snowstorm | Massachusetts Department of Transportation | $883,164.59 |
| DR-4051-MA | 2012-01-06 | Severe Storm and Snowstorm | Massachusetts Bay Transportation Authority | $132,924.88 |
| DR-4051-MA | 2012-01-06 | Severe Storm and Snowstorm | Environmental Protection, Department of | $4,081.96 |
| DR-4051-MA | 2012-01-06 | Severe Storm and Snowstorm | Conservation and Recreation, Department of | $207,997.85 |
| DR-1994-MA | 2011-06-15 | Severe Storms and Tornadoes | Department of Developmental Services | $10,552.72 |
| DR-1813-MA | 2009-01-05 | Severe Winter Storm and Flooding | Massachusetts Water Resources Authority | $27,831.63 |
| DR-1813-MA | 2009-01-05 | Severe Winter Storm and Flooding | Massachusetts Department of Transportation | $1,741,408.88 |
| DR-1813-MA | 2009-01-05 | Severe Winter Storm and Flooding | MA Department of Youth Services | $993.75 |
| DR-1813-MA | 2009-01-05 | Severe Winter Storm and Flooding | Environmental Protection, Department of | $5,810.65 |
| DR-1813-MA | 2009-01-05 | Severe Winter Storm and Flooding | Department of Developmental Services | $10,627.06 |
| DR-1813-MA | 2009-01-05 | Severe Winter Storm and Flooding | Conservation and Recreation, Department of | $7,041,783.46 |
| DR-1701-MA | 2007-05-16 | Severe Storms and Inland and Coastal Flooding | Massachusetts Environmental Police | $3,505.67 |
| DR-1701-MA | 2007-05-16 | Severe Storms and Inland and Coastal Flooding | Massachusetts Department of Transportation | $68,292.72 |
| DR-1701-MA | 2007-05-16 | Severe Storms and Inland and Coastal Flooding | Conservation and Recreation, Department of | $779,614.22 |
| EM-3264-MA | 2005-10-19 | Severe Storms and Flooding | Massachusetts Department of Transportation | $6,723.51 |
| EM-3165-MA | 2001-03-28 | Snow | Massachusetts Department of Transportation | $7,012,518.15 |
| EM-3165-MA | 2001-03-28 | Snow | Massachusetts Bay Transportation Authority | $282,540.29 |
| EM-3153-MA | 1999-12-06 | Warehouse Fire. | Office of the Chief Medical Examiner | $25,579.81 |
| EM-3153-MA | 1999-12-06 | Warehouse Fire. | Massachusetts Department of Transportation | $25,171.54 |
FEMA's Public Assistance summaries file these applicants under this county, but FEMA's declaration rows for these disasters do not designate it (an electric cooperative or district serving several counties, for example). Not in any declaration row above and not counted.
Previous occurrences by hazard, with explicit no-event rows
Sources: 2, 6, 7
| Hazard | Storm Events records, all years on file(years in the Period column) | Since plan approvalrecords | In the 12 months before plan approvalrecords | Last 5 yearsrecords | Declared incidents, all yearsseparate disasters | Declared since approvalseparate disasters | Period | Statement |
|---|---|---|---|---|---|---|---|---|
| Coastal Flooding | 50 | 7 | 3 | 1996 to 2026-06-30 | ||||
| Cold Wave | 8 | 0 | 0 | 1996 to 2026-06-30 | ||||
| Drought | 11 | 0 | 0 | 1996 to 2026-06-30 | ||||
| Earthquake | 0 | 0 | 0 | Storm Events does not record earthquakes; the USGS earthquake catalog is the source. | ||||
| Hail | 24 | 0 | 0 | 1955 to 2026-06-30 | ||||
| Heat Wave | 21 | 0 | 0 | 1996 to 2026-06-30 | ||||
| Hurricane | 4 | 0 | 6 | 1996 to 2026-06-30 | ||||
| Ice Storm | 0 | 0 | 0 | 1996 to 2026-06-30 | No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events | |||
| Inland Flooding | 72 | 16 | 9 | 1996 to 2026-06-30 | ||||
| Landslide | 0 | 0 | 0 | 1996 to 2026-06-30 | No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events | |||
| Lightning | 19 | 1 | 0 | 1996 to 2026-06-30 | ||||
| Strong Wind | 306 | 27 | 0 | 1955 to 2026-06-30 | Includes 76 High Wind and 100 Strong Wind records. | |||
| Tornado | 1 | 0 | 0 | 1950 to 2026-06-30 | ||||
| Tsunami | 0 | 0 | 0 | 1996 to 2026-06-30 | No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events | |||
| Wildfire | 0 | 0 | 0 | 1996 to 2026-06-30 | No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events | |||
| Winter Weather | 99 | 6 | 12 | 1996 to 2026-06-30 |
Notable Storm Events records
Sources: 1, 6, 7
| Date | Event type | Magnitude or extent | Damagenominal dollars | Deaths, injuriesdirect only | Location | Why listed |
|---|---|---|---|---|---|---|
| 2015-08-04 | Hail | 2 in | $0 property; $0 crops (2015 dollars) | 0, 0 | FOREST HILLS | B1-c worst recorded: Hail |
| 2014-07-28 | Tornado | EF2, 1.93 mi within this county, 660 yd wide | $4,000,000 property; $0 crops (2014 dollars) | 0, 2 | CHELSEA to REVERE | B1-c worst recorded: Tornado |
| 2012-10-29 | Coastal Flood | $3,000,000 property; $0 crops (zone total, 2012 dollars) | 0, 0 | NWS zone MAZ015 (SUFFOLK), zone-level | B1-c worst recorded: Coastal Flood, Storm Surge/Tide | |
| 2011-08-28 | Tropical Storm | $3,450,000 property; $0 crops (zone total, 2011 dollars) | 0, 0 | NWS zone MAZ015 (SUFFOLK), zone-level | B1-c worst recorded: Hurricane, Tropical Storm, Tropical Depression | |
| 2010-08-05 | Lightning | $0 property; $0 crops (2010 dollars) | 1, 0 | SOUTH BOSTON | deaths or injuries recorded | |
| 2007-02-03 | Extreme Cold/Wind Chill | $0 property; $0 crops (zone total, 2007 dollars) | 1, 0 | NWS zone MAZ015 (SUFFOLK), zone-level | deaths or injuries recorded | |
| 2006-01-18 | High Wind | 68 kt (78 mph) measured gust | $100,000 property; crops not reported (zone total, 2006 dollars) | 0, 0 | NWS zone MAZ015 (SUFFOLK / ALSO PART OF NORFOLK), zone-level | B1-c worst recorded: High Wind and Strong Wind |
| 2001-05-03 | Excessive Heat | damage not reported | 0, 0 | NWS zone MAZ015 (SUFFOLK / ALSO PART OF NORFOLK), zone-level | B1-c worst recorded: Excessive Heat, Heat | |
| 2001-03-05 | Flood | $15,000,000 property; crops not reported (zone total, 2001 dollars) | 0, 0 | NWS zone MAZ015 (SUFFOLK), zone-level | B1-c worst recorded: Flash Flood, Flood, Lakeshore Flood | |
| 1999-07-05 | Heat | damage not reported | 2, 0 | NWS zone MAZ015 (SUFFOLK / ALSO PART OF NORFOLK), zone-level | deaths or injuries recorded | |
| 1996-01-07 | Heavy Snow | $7,000,000 property; crops not reported (zone total, 1996 dollars) | 0, 0 | NWS zone MAZ015 (SUFFOLK), zone-level | B1-c worst recorded: Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet | |
| 1956-06-13 | Thunderstorm Wind | 73 kt (84 mph), measurement type not recorded | damage not recorded (pre-1996 record) | 0, 0 | location not recorded | B1-c worst recorded: Thunderstorm Wind |
The full list is in the Excel file, sheet "B1-d Storm Events history" (615 rows).
Location is the place NOAA recorded, as written in its data; it need not be a jurisdiction in this plan.
Local data needed: state-declared emergencies, from your state emergency management agency (federal data do not include them).
Tribal and special-area declarations in this state are listed on the state page.
Supports FEMA checklist item B1-e: probability of future events
Probability: FEMA annualized frequency and descriptor per hazard
Sources: 5, 6
| Hazard | FEMA annualized frequency (modeled)unit per row | Unit | In plain terms | Descriptor | Descriptor basis | NRI events or days in its record period (hail, wind and tornado are area-weighted, so can be fractional) | NRI period | Location | Note |
|---|---|---|---|---|---|---|---|---|---|
| Coastal Flooding | 7.4 | events per year at a location (modeled) | about 7.4 per year at a given location in the county | Highly likely | FEMA annualized frequency (modeled) | not shown | modeled | see B1-f | Descriptor from NRI: the rate at a location is 1 or more a year, so the county rate is at least that. |
| Cold Wave | 1.19 | event-days per year | about 1.19 days per year | Likely | Storm Events event-days in 6 of 30 years, 1996 to 2025 (20%) | 11.6 | 2005-11-12 to 2024-11-12 (19 years) | countywide | |
| Drought | 6.68 | event-days per year | about 6.68 days per year | Likely | Storm Events event-days in 4 of 30 years, 1996 to 2025 (13.3%) | 196 | 2000 to 2025 (25.25 years; D3 and D4 only) | countywide | |
| Earthquake | 0.00173 | annual probability at a location | chance a given location in the county has at least minor-damage shaking in a year: 0.173% | not shown | modeled | see B1-f | No descriptor (Storm Events does not record earthquakes). | ||
| Hail | 1.64 | events per year | about 1.64 per year | Highly likely | FEMA annualized frequency (modeled) | 68.4 (modeled) | 1986 to 2023 (38 years) | countywide | |
| Heat Wave | 5.25 | event-days per year | about 5.25 days per year | Likely | Storm Events event-days in 9 of 30 years, 1996 to 2025 (30%) | 44.9 | 2005-11-12 to 2024-11-12 (19 years) | countywide | |
| Hurricane | 0.184 | events per year | about 1 in 5 years | Likely | FEMA annualized frequency (modeled) | 48 | 1851 to 2024 (Atlantic) | see B1-f | NRI counts hurricane and tropical storm tracks passing within storm-force wind range; federal declarations are in B1-d. |
| Ice Storm | 1.01 | event-days per year | about 1.01 days per year | Storm Events event-days in 0 of 30 years, 1996 to 2025 (0%) | 39 | 1946-12-31 to 2014-02-12 (67 years) | countywide | No Storm Events ice storm record, 1996 to 2025 | |
| Inland Flooding | 1.68 | event-days per year | about 1.68 days per year | Likely | Storm Events event-days in 20 of 30 years, 1996 to 2025 (66.7%) | 47 | 1996 to 2023 (28 years) | see B1-f | |
| Landslide | 0.0178 | events per year (modeled) | about 1 in 56 years | Possible | FEMA annualized frequency (modeled) | not shown | modeled | see B1-f | |
| Lightning | 20 | days per year with a strike | about 20 days per year | Highly likely | FEMA annualized frequency (modeled) | not shown | 1995 to 2023 (29 years; CONUS) | countywide | |
| Strong Wind | 0.704 | events per year | about 0.7 per year | Likely | FEMA annualized frequency (modeled) | 16 | 1986 to 2023 (38 years) | countywide | |
| Tornado | 0.0184 | events per year | about 1 in 54 years | Possible | FEMA annualized frequency (modeled) | not shown | 1950 to 2023 (EF2+); 1986 to 2023 (EF0-1) | see B1-f | |
| Tsunami | annual probability at the most exposed location (used in place of a county value) | Storm Events records in 0 of 30 years, 1996 to 2025 (0%) | not shown | modeled | see B1-f | No descriptor: no Storm Events record 1996 to 2025 | |||
| Wildfire | 0.0000227 | annual probability at a location | chance a given location in the county burns in a year: 0.00227% | Storm Events records in 0 of 30 years, 1996 to 2025 (0%) | not shown | modeled | see B1-f | No descriptor: no Storm Events record 1996 to 2025 | |
| Winter Weather | 12.2 | event-days per year | about 12.2 days per year | Highly likely | Storm Events event-days in 28 of 30 years, 1996 to 2025 (93.3%) | 120 | 2005-11-12 to 2024-11-12 (19 years) | countywide |
FEMA annualized frequency (modeled) is the National Risk Index v1.20 (December 2025) estimate of how often a hazard affects this county in a year; it is not recorded events divided by years, and its unit differs by hazard (events, event-days, or days with a lightning strike per year). For earthquake, wildfire, coastal flooding and tsunami the value is the chance (or number of events) at a location in the county, not across the county, so no "1 in N years" is given and the descriptor comes from Storm Events where it has a record (none for earthquake). The Methods page gives each hazard's method, from FEMA's National Risk Index Technical Documentation v1.20.
Where NRI gives event-days, the descriptor comes from the share of years with a Storm Events record; NRI's source records more events, so the two differ.
Descriptor scale used in this packet (defined per unit)
Sources: 5, 6
| Unit | Descriptor | Definition |
|---|---|---|
| events per year | Highly likely | 1 or more per year |
| events per year | Likely | about once in 1 to 10 years |
| events per year | Possible | about once in 10 to 100 years |
| events per year | Unlikely | less than once in 100 years |
| annual probability | Likely | 10% to under 100% chance in a given year |
| annual probability | Possible | 1% to under 10% chance in a given year |
| annual probability | Unlikely | under 1% chance in a given year |
| event-days (share of years) | Highly likely | event-days recorded in 90% or more of years |
| event-days (share of years) | Likely | event-days recorded in 10% to under 90% of years |
| event-days (share of years) | Possible | event-days recorded in some years but under 10% of years |
| lightning strike-days | Highly likely | cloud-to-ground strikes on 1 or more days per year |
Intensity bands: historical frequency (Storm Events)
Source: 6
| Hazard | Band | Years | Eventscounty-coded records | Years in period | Events per yearevents / years |
|---|---|---|---|---|---|
| Hail | 1.00-1.99 in | 1996 to 2025 | 6 | 30 | 0.2 |
| Hail | 2.00 in+ | 1996 to 2025 | 1 | 30 | 0.0333 |
| Thunderstorm Wind (counted as NRI Strong Wind) | 50-64 kt | 1996 to 2025 | 99 | 30 | 3.3 |
| Thunderstorm Wind (counted as NRI Strong Wind) | 65 kt+ | 1996 to 2025 | 1 | 30 | 0.0333 |
| Thunderstorm Wind (counted as NRI Strong Wind) | unmeasured or below 50 kt | 1996 to 2025 | 1 | 30 | 0.0333 |
| Tornado | EF0-1 | 1996 to 2025 | 0 | 30 | 0 |
| Tornado | EF2-3 | 1996 to 2025 | 1 | 30 | 0.0333 |
| Tornado | EF4-5 | 1996 to 2025 | 0 | 30 | 0 |
| Tornado | unrated (EFU) | 1996 to 2025 | 0 | 30 | 0 |
The bands show how often events of each severity were recorded in this county, to profile how severe events have been (FEMA's probability item asks for the range of intensities).
Hail smaller than 1 inch is not counted: on 2010-01-05 the National Weather Service raised its severe-hail threshold from 3/4 inch to 1 inch, so smaller reports became less common after 2009 (NWS Service Change Notice 09-52). NRI hail frequency uses a 0.75 inch threshold.
Optional: future conditions. Not a required item in the 2025 FEMA Local Mitigation Planning Policy Guide; some states ask for it. The federal Climate Mapping for Resilience and Adaptation (CMRA) site gives county exposure to future climate conditions (https://resilience.climate.gov/).
Supports FEMA checklist item B1-f: hazards that vary across jurisdictions
Range of census tract risk within the county
Source: 5
| Hazard | Tractsrated of all | NRI risk score, 0 to 100 | Tracts by rating | ||
|---|---|---|---|---|---|
| Min | Median | Max | |||
| Coastal Flooding | 97 of 234 | 69.5 | 87.0 | 99.6 | Very High 3, Relatively High 8, Relatively Moderate 31, Relatively Low 30, Very Low 25, No Rating 137 |
| Cold Wave | 234 of 234 | 15.5 | 42.9 | 73.0 | Relatively Moderate 90, Relatively Low 128, Very Low 16 |
| Drought | 0 of 234 | No Rating 234 | |||
| Earthquake | 234 of 234 | 1.2 | 53.9 | 86.3 | Relatively Moderate 12, Relatively Low 168, Very Low 54 |
| Hail | 234 of 234 | 1.0 | 30.9 | 72.0 | Relatively Moderate 1, Relatively Low 49, Very Low 184 |
| Heat Wave | 234 of 234 | 1.3 | 52.5 | 85.8 | Relatively High 1, Relatively Moderate 102, Relatively Low 110, Very Low 21 |
| Hurricane | 234 of 234 | 29.2 | 67.3 | 90.2 | Relatively High 1, Relatively Moderate 18, Relatively Low 201, Very Low 14 |
| Ice Storm | 234 of 234 | 0.1 | 18.7 | 62.7 | Relatively Low 24, Very Low 210 |
| Inland Flooding | 234 of 234 | 0.2 | 10.0 | 81.6 | Relatively High 2, Relatively Moderate 15, Relatively Low 80, Very Low 137 |
| Landslide | 230 of 234 | 8.8 | 28.7 | 74.5 | Very Low 230, No Rating 4 |
| Lightning | 234 of 234 | 0.2 | 46.6 | 87.8 | Relatively High 3, Relatively Moderate 96, Relatively Low 112, Very Low 23 |
| Strong Wind | 234 of 234 | 0.3 | 13.6 | 41.0 | Relatively Low 19, Very Low 215 |
| Tornado | 234 of 234 | 0.4 | 22.3 | 57.4 | Relatively Moderate 1, Relatively Low 32, Very Low 201 |
| Tsunami | 0 of 234 | Insufficient Data 234 | |||
| Wildfire | 58 of 234 | 18.5 | 24.2 | 61.7 | Very Low 58, No Rating 176 |
| Winter Weather | 234 of 234 | 10.7 | 17.9 | 35.8 | Relatively Low 104, Very Low 130 |
Rated tracts only: No Rating (score 0.0), Not Applicable and Insufficient Data tracts are counted but not used for the minimum, median and maximum.
The score ranks a tract against all U.S. tracts (100 = highest). The rating is FEMA's category for the tract's risk value, computed differently, so the two can disagree.
Frequency data for cold wave, hail, heat wave, ice storm, lightning, strong wind and winter weather are county-wide or coarse (49 km grid or NWS zone), the same for every jurisdiction; the tract range mostly reflects where buildings and people are.
Each jurisdiction (starting figures from federal data)
Sources: 1, 3, 4, 6
| Jurisdiction | Type | Plan status | Repetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definition | Public Assistance to this jurisdictionFEMA records matched by applicant name; federal share obligated, nominal dollars | Event records naming this placeall years; since its plan | Notes |
|---|---|---|---|---|---|---|
| Boston city | City | Approved, expires 2026-12-05 | FMA RL 0, SRL 1; any 26 | $45,961,014.74 | 52 total; 3 since its plan | Includes $18,681,437.54 for declarations not counted as hazard incidents (DR-4496-MA, EM-3362-MA). |
| Chelsea city | City | Approved, expires 2027-07-11 | FMA RL 0, SRL 0; any 2 | $1,661,694.79 | 12 total; 1 since its plan | Includes $1,021,810.19 for declarations not counted as hazard incidents (DR-4496-MA, EM-3362-MA). |
| Revere city | City | Approved, expires 2027-02-16 | FMA RL 0, SRL 38; any 289 | $3,826,049.73 | 31 total; 5 since its plan | Includes $2,430,637.03 for declarations not counted as hazard incidents (DR-4496-MA). |
| Winthrop Town city | City | Approved, expires 2031-08-13 | FMA RL 0, SRL 12; any 154 | no Public Assistance recorded | 0 total; not yet covered |
Repetitive-loss counts are for whole NFIP communities, which can extend beyond this county (see the note in B2-c).
School districts and special districts get a plan clock row only.
County Public Assistance in B1-d also includes applicants filed under the county that are not jurisdictions in this plan (for example state agencies, special districts and nonprofits), so the jurisdiction rows add up to less.
Supports FEMA checklist items B2-a and B2-b: vulnerability and potential impacts
Local data needed
The table below gives county-level starting figures; the plan describes impacts for each jurisdiction and its own assets.
No county-level plan row in FEMA data, so there is no approval date to count from.
- Critical facilities and lifelines per hazard
- A problem statement per jurisdiction per hazard
- Changes in development in hazard-prone areas since the last approval, or a statement of none (E1-a)
- Future assets
County-level starter: exposure, expected annual loss and damage since the plan
Sources: 1, 2, 3, 5, 6, 7
| Hazard | Building exposuremodeled dollars | Agriculture exposuremodeled dollars | Population exposedpeople | EAL buildingsmodeled dollars per year | EAL agriculturemodeled dollars per year | Cost of expected deaths and injuriesFEMA's dollar value per year, not property damage | EAL as % of exposurebuildings; agriculture where noted | Storm Events damage since plancounty-coded records, property plus crops, nominal dollars | Zone-level damage since planproperty plus crops, reported for the zone | Public Assistance since plannominal dollars; see note | Note |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Coastal Flooding | $12,374,361,444 | n/a | 59,451 | $5,228,356 | n/a | $1,059,907 | 0.0423% | ||||
| Cold Wave | $133,076,607,263 | $670,845 | 796,207 | $677 | $64 | $8,677,694 | under 0.0001% | ||||
| Drought | n/a | $0 | n/a | n/a | $0 | n/a | agriculture exposure is 0 in NRI | ||||
| Earthquake | $243,464,287,315 | n/a | 797,936 | $8,238,651 | n/a | $3,411,770 | 0.00338% | ||||
| Hail | $133,088,168,367 | $670,845 | 796,326 | $598,469 | $2 | $16,652 | 0.00045% | ||||
| Heat Wave | $133,079,559,396 | $670,845 | 796,237 | $30 | $82 | $9,433,664 | under 0.0001% | ||||
| Hurricane | $133,027,789,050 | $670,845 | 795,879 | $12,415,981 | $5,559 | $501,711 | 0.00933% | ||||
| Ice Storm | $131,146,908,792 | n/a | 786,428 | $129,801 | n/a | $199,097 | under 0.0001% | ||||
| Inland Flooding | $132,925,403,810 | $49,371 | 42,435 | $59,469,894 | $313 | $47,960 | n/a (see note) | NRI counts the full building value of any census block with some flood loss; this is not the value of buildings in the floodplain. Use local FIRM overlays for B2-a/B2-b. | |||
| Landslide | $2,456,588,289 | n/a | 16,844 | $367 | n/a | $39 | under 0.0001% | ||||
| Lightning | $133,088,168,367 | n/a | 796,326 | $409,876 | n/a | $1,908,214 | 0.000308% | ||||
| Strong Wind | $133,088,168,367 | $670,845 | 796,326 | $224,347 | under $1 | $255,897 | 0.000169% | ||||
| Tornado | $133,088,168,367 | $670,845 | 796,326 | $2,217,516 | $5 | $378,485 | 0.00167% | ||||
| Tsunami | n/a | n/a | n/a | n/a | n/a | n/a | NRI publishes no building exposure for this county | ||||
| Wildfire | $1,202,648,115 | $108,944 | 8,543 | $2,076 | under $1 | $290 | 0.000173% | ||||
| Winter Weather | $133,081,860,865 | $670,845 | 796,260 | $26,709 | under $1 | $16,678 | under 0.0001% |
Totals since the plan: not available. No county-level plan row in FEMA data, so there is no approval date to count from.
FEMA does not split Public Assistance by hazard. A declaration mapped to several hazards is listed under each of them with its full amount, so the per-hazard column does not add up to the total; the unit total counts each declaration once.
NRI computes earthquake exposure on its own basis, so it exceeds the county building value in B2-a.
Supports FEMA checklist item B2-a: vulnerability (county context)
County context
Source: 5
| Measure | Value |
|---|---|
| Population | 796,326 |
| Building value (total, not at risk) | $133,088,168,367 |
| Agriculture value (total, not at risk) | $670,845 |
| NRI risk rating (all hazards) | Relatively Moderate |
| Expected annual loss, buildings and agriculture, all hazards | $88,968,776 |
| Expected annual loss, population equivalence, all hazards (NRI values each statistical life at $13.7M; a modeled value of expected deaths and injuries, not property damage) | $25,908,058 |
| Social vulnerability rating | Relatively High |
| Community resilience rating | Very High |
| NRI version | December 2025 |
FEMA's all-hazard expected annual loss adds buildings, agriculture and population equivalence; this table gives the property part and the population-equivalence part as separate rows.
Social vulnerability: higher means people are more likely to be harmed and slower to recover. Community resilience: lower means the community is less able to recover. High social vulnerability and low resilience both raise the NRI risk rating.
Supports FEMA checklist item B2-c: repetitive loss properties
Repetitive loss in this county, both definitions
Sources: 1, 4
| Definition | Properties | Severe repetitive loss | Properties |
|---|---|---|---|
| Repetitive loss, FMA definition (44 CFR 77.2) | 0 | Severe repetitive loss, FMA definition (44 CFR 77.2) | 52 |
| Repetitive loss, NFIP insurance definition | 466 | Severe repetitive loss, NFIP insurance definition | 45 |
The state NFIP coordinator's list, the source FEMA's Handbook names, often uses the NFIP insurance definition (second row).
Repeat-flood properties: county total and NFIP communities
Sources: 1, 4
| Scope | RL, FMAproperties | SRL, FMAproperties | RL, NFIPproperties | SRL, NFIPproperties | Any categoryproperties | Mitigatedproperties | Currently insuredproperties |
|---|---|---|---|---|---|---|---|
| County total | 0 | 52 | 466 | 45 | 472 | 4 | 143 |
| of which: Boston city | 0 | 1 | 26 | 1 | 26 | 0 | 9 |
| of which: Chelsea city | 0 | 0 | 2 | 0 | 2 | 0 | 1 |
| of which: Revere city | 0 | 38 | 284 | 32 | 289 | 4 | 79 |
| of which: Winthrop town | 0 | 12 | 153 | 11 | 154 | 0 | 54 |
| of which: Unknown (community ID Unknown in FEMA data) | 0 | 1 | 1 | 1 | 1 | 0 | 0 |
Repeat-flood properties by jurisdiction in the plan (NFIP community)
Sources: 1, 4
| Jurisdiction | NFIP community ID | RL, FMAproperties | SRL, FMAproperties | RL, NFIPproperties | SRL, NFIPproperties | Any categoryproperties | Mitigatedproperties | Currently insuredproperties |
|---|---|---|---|---|---|---|---|---|
| Boston city | 250286 | 0 | 1 | 26 | 1 | 26 | 0 | 9 |
| Chelsea city | 250287 | 0 | 0 | 2 | 0 | 2 | 0 | 1 |
| Revere city | 250288 | 0 | 38 | 284 | 32 | 289 | 4 | 79 |
| Winthrop Town city | 250289 | 0 | 12 | 153 | 11 | 154 | 0 | 54 |
Counts by occupancy group for each jurisdiction are in the Excel file, sheet "B2-c Jurisdictions".
Jurisdiction rows are whole NFIP communities and need not add up to the county total: a community that extends into another county is counted in full on each jurisdiction row, while the county table counts only its part in this county.
County repeat-flood properties by occupancy group
Sources: 1, 4
| Occupancy group | RL, FMAproperties | SRL, FMAproperties | RL, NFIPproperties | SRL, NFIPproperties | Any categoryproperties | Mitigatedproperties | Currently insuredproperties |
|---|---|---|---|---|---|---|---|
| single-family residential | 0 | 24 | 275 | 19 | 279 | 3 | 96 |
| 2 to 4 unit residential | 0 | 22 | 146 | 20 | 148 | 1 | 34 |
| other residential | 0 | 3 | 25 | 3 | 25 | 0 | 8 |
| non-residential | 0 | 3 | 20 | 3 | 20 | 0 | 5 |
| not reported | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
FEMA's occupancy groups have no institutional class; institutional properties are counted in non-residential or other residential in the table by occupancy group.
FMA RL and FMA SRL are the Flood Mitigation Assistance definitions (44 CFR 77.2), the ones the FEMA Local Mitigation Planning Policy Guide cites. NFIP repetitive loss (the FEMA insurance definition) is 2 or more claims over $1,000 in 10 years, and a property can leave that group once it is mitigated. Also shown: NFIP severe repetitive loss, any category, mitigated and currently insured. The Methods page gives the OpenFEMA field details.
Counts are aggregates of FEMA's public NFIP Multiple Loss Properties file (FEMA's data date 2026-08-02; file version 2026-08-04). No property is identified. County assignment is FEMA's geocode.
In this county 0 properties are FMA repetitive loss but not NFIP repetitive loss, and 466 properties are NFIP repetitive loss but not FMA repetitive loss.
Exact counts; no count suppression.
Sources
Tables cite these sources by number. The full list, for the plan's bibliography (FEMA review item A4-a):
- FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-29T134039Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)
- FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-29T162832Z, pulled 2026-09-30, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)
- FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-29T150754Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)
- FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)
- FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-30, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)
- NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-30, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/
- NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-30, https://www.weather.gov/gis/ZoneCounty
- U.S. Census Bureau, Census 2024 Gazetteer, 2020 place by county, CT county-to-cousub crosswalk, version 2024-gazetteer, pulled 2026-09-30, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_counties_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_cousubs_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_place_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_unsd_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_elsd_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_scsd_national.zip, https://www2.census.gov/geo/docs/reference/codes2020/national_place_by_county2020.txt, https://www2.census.gov/geo/docs/reference/ct_change/ct_cou_to_cousub_crosswalk.xlsx (used to match place names and codes; no table prints its values)
What this packet is and what the plan adds
This packet is the federal data for the plan's risk assessment (the summary on page 1 says how it is organized); the plan and FEMA's review decide whether each item is met.
The plan adds what only the community has: local data on assets, critical facilities, development and each jurisdiction's impacts; local hazard history, including state-declared emergencies; the mitigation strategy; and adoption.
How the federal data are built: National Risk Index values are FEMA's model, not counts of events. Storm Events is more complete from 1996; zone-level records are placed by forecast zone, not by location in the county. Public Assistance for a jurisdiction is matched by applicant name. The Methods page gives every rule and the known edge cases.
OpenFEMA disclaimer
This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Reuse, citation and corrections
Reuse and citation: Hazard Plain text and tables are licensed under Creative Commons Attribution 4.0 International (CC BY 4.0, https://creativecommons.org/licenses/by/4.0/); credit Hazard Plain and the release. The underlying federal data are public domain; OpenFEMA data are also subject to the OpenFEMA terms and conditions.
Cite this: Hazard Plain (2026). Suffolk County, MA: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 25025). Automated baseline. https://hazardplain.org/ma/25025/ Built from FEMA OpenFEMA, the FEMA National Risk Index and NOAA NCEI Storm Events; source versions in the packet's Sources list.
Corrections: to report an error, name the packet, the table and what your records show. Contact: [email protected]