Hazard Plain Automated baseline

Martin County, MN

Risk-assessment baseline packet

County FIPS:
27091
Release:
2026-10
Data as of:
2026-09-30
Storm Events data through:
2026-06-30

Hazard Plain is an independent product built from public federal data. It is not a FEMA document and is not reviewed or endorsed by FEMA or any state agency.

Hazard Plain release 2026-10, as of 2026-09-30.

Summary

Plan status as of 2026-09-30: Expired on 2025-09-27. Plan: Martin County (FEMA plan 106506), approved 2020-09-28.

Since the plan was approved on 2020-09-28: 1 new hazard declaration (1 incident) and 71 NOAA Storm Events records; details under "What changed since your last plan".

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($4,299,192 a year), Cold Wave ($2,360,279) and Tornado ($2,179,934).

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

Status:
Expired on 2025-09-27
Plan:
Martin County (FEMA plan 106506)
Approved:
2020-09-28
Days since expiry:
368
Update underway:
none recorded in FEMA's plan tracker

Until a new plan is approved, FEMA mitigation project grants (HMGP, FMA) need a FEMA exception (44 CFR 201.6(a)(3)).

What changed since your last plan (approved 2020-09-28)

New federal declarations:
1 new hazard declaration (1 incident): DR-4797-MN (Severe Storms and Flooding)
Storm Events records since approval:
71 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 0, SRL 0 (44 CFR 77.2); any definition: 0
Repeat-flood change:
this release sets the baseline count.

Sources: 1, 2, 4, 6 (numbered list at the end)

Plan status for every jurisdiction listed in this county

Source: 1

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiryUpdate underwayNotes
Martin CountyCountyExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Ceylon cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Dunnell cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Fairmont cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Granada cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Northrop cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Ormsby cityCityPlan 108132 approved 2022-12-19, pending adoption here; not yet eligibleWatonwan County (FEMA plan 108132), pending adoption here2022-12-19 by FEMA; not yet adopted here2027-12-18 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Sherburn cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Trimont cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Truman cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368
Welcome cityCityExpired on 2025-09-27Martin County (FEMA plan 106506)2020-09-282025-09-27-368

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 EALHazardNRI risk ratingEAL ratingEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearCost of expected deaths and injuriesFEMA's dollar value per year, not property damageEAL total (see note)modeled dollars per yearStorm Events records, 1996 to 2026-06-30countWhy this hazard can be left outNRI Not Applicable, no declaration and no Storm Events record since 1996Storm Events coverage note
1Inland FloodingRelatively LowRelatively Low$4,240,262$57,343$1,587$4,299,19222
2Cold WaveRelatively ModerateRelatively Moderate$1,727$402,956$1,955,596$2,360,27930Includes 1 Frost/Freeze record (outside NRI's Cold Wave definition; counted in this table and in B1-d, not in the B1-e descriptor).
3TornadoRelatively ModerateRelatively Moderate$1,513,954$19,678$646,303$2,179,93411
4HailRelatively ModerateRelatively Moderate$196,785$1,161,105$52,176$1,410,066114
5Strong WindRelatively ModerateRelatively Moderate$675,099$271,986$141,890$1,088,974112Includes 17 High Wind records (a NOAA non-thunderstorm wind type, outside NRI's Strong Wind definition).
6DroughtRelatively ModerateRelatively Moderaten/a$1,017,476n/a$1,017,4760Declared 1 time; no Storm Events record of this type.
7Winter WeatherRelatively HighRelatively High$186,332$5,845$153,912$346,089119
8Heat WaveRelatively LowRelatively Low$6,598$12$222,886$229,49611
9Ice StormRelatively LowRelatively Low$62,040n/a$4,763$66,8033
10LightningVery LowVery Low$9,433n/a$54,434$63,8671
11EarthquakeVery LowVery Low$11,425n/a$2,881$14,306Storm Events does not record earthquakes.
12WildfireVery LowVery Low$5,329$162$332$5,8230No recorded events in Storm Events since 1996 (data through 2026-06-30).
13LandslideVery LowVery Low$45n/a$295$3400Declared 1 time; no Storm Events record of this type.
HurricaneNot ApplicableNot Applicable0NRI rates hurricane Not Applicable for this county, and no counted federal declaration for this county names it (EM-3242-MN names it but is not counted as a local occurrence; see B1-d).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 and landslide 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, coastal flooding, tsunami 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.

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

HazardHighest-rated census tractsNRI risk rating, score 0 to 100
Earthquaketract 7906 (Very Low, 17.4); tract 7901 (Very Low, 13.3); tract 7905.02 (Very Low, 9.8)
Hurricaneno tract has a National Risk Index rating for this hazard
Landslidetract 7904 (Relatively Low, 81.0); tract 7902 (Very Low, 79.2); tract 7901 (Very Low, 78.0)
Tornadotract 7906 (Very High, 97.3); tract 7905.02 (Relatively High, 91.5); tract 7901 (Relatively High, 91.3)
Wildfiretract 7903 (Relatively Low, 69.8); tract 7902 (Very Low, 67.6); tract 7901 (Very Low, 67.6)

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 7906 is Census Tract 7906). 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

HazardScaleRecordscount and yearsObserved rangeWorst recorded eventMost damaging (when different)How it applies to jurisdictionsNote
Cold/Wind Chill, Extreme Cold/Wind Chillwind chill29 records, 1996 to 2026 (29 zone-level)1 day to 5 days (median 2 days); 26 with a recorded value5 consecutive days, 1996-01-31 to 1996-02-04, zone-levelCountywide (zone-level records).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage1 record, 2012 (1 zone-level)Frost/Freeze, 2012-04-10, $20,000 crop damage (2012 dollars); NWS zone MNZ091Countywide (zone-level records).
DroughtU.S. Drought Monitor scale (D0 to D4)0Storm 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.
EarthquakeModified Mercalli (local data)0Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hailhail size (inches)140 records, 1958 to 20260.75 in to 3 in (median 1 in); 140 with a recorded value3 in hail, 1965-05-06Event records naming jurisdictions in the plan: Fairmont city (26 records), Truman city (14 records), Welcome city (14 records), Sherburn city (13 records), Trimont city (12 records), Ceylon city (4 records), Dunnell city (4 records), Northrop city (4 records), Granada city (3 records), Ormsby city (3 records).
Excessive Heat, Heatheat index (in event narratives)11 records, 1999 to 2023 (11 zone-level)1 day to 5 days (median 2.5 days); 10 with a recorded value5 consecutive days, 2001-08-04 to 2001-08-08, zone-levelCountywide (zone-level records).
Hurricane, Tropical Storm, Tropical DepressionSaffir-Simpson0Storm 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 StormSperry-Piltz ice scale (local data)3 records, 1996 to 2023 (3 zone-level)No damage reported in 3 records.Countywide (zone-level records).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)22 records, 1997 to 2025 (4 zone-level)Flood, 2004-09-15, $570,000 property; $3,700,000 crops (2004 dollars); NWS zone MNZ091Event records naming jurisdictions in the plan: Fairmont city (3 records), Truman city (3 records), Dunnell city (2 records), Sherburn city (2 records), Trimont city (2 records), Welcome city (2 records), Ceylon city (1 record), Granada city (1 record), Ormsby city (1 record). Zone-level records (4) 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 Flownone (count and damage only)0
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)1 record, 2014Lightning, 2014-04-06, $45,000 property; $0 crops (2014 dollars)No event record names a jurisdiction in the plan.Storm Events lists lightning with damage or casualties.
High Wind and Strong Wind (outside NRI's Strong Wind definition)wind speed (kt and mph)17 records, 1996 to 2026 (17 zone-level)35 kt (40 mph) to 69 kt (79 mph) (median 52 kt (60 mph)); 17 with a recorded value69 kt (79 mph) measured, High Wind, 2001-04-07; NWS zone MNZ091High Wind, 2015-06-22, $100,000 property; $0 crops (zone total, 2015 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)143 records, 1956 to 202650 kt (58 mph) to 85 kt (98 mph) (median 55 kt (63 mph)); 113 with a recorded value85 kt (98 mph), measurement type not recorded, Thunderstorm Wind, 1975-05-22Thunderstorm Wind, 1998-05-15, $1,000,000 property; crops not reported (1998 dollars)Event records naming jurisdictions in the plan: Fairmont city (33 records), Welcome city (10 records), Ceylon city (9 records), Sherburn city (8 records), Trimont city (7 records), Dunnell city (5 records), Truman city (4 records), Northrop city (3 records), Granada city (2 records).
TornadoEnhanced Fujita (Fujita before Feb 2007)23 records, 1951 to 2026F/EF0 to F/EF2 (median F/EF0); 22 with a recorded valueF2 tornado, 1951-06-25, 14.2 mi path length (whole path, pre-1996), 33 yd wide, $250,000 property; crops not recorded (1951 dollars)Tornado, 2018-09-20, $1,500,000 property; $0 crops (2018 dollars)Event records naming jurisdictions in the plan: Granada city (3 records), Fairmont city (2 records), Ceylon city (1 record), Northrop city (1 record), Trimont 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).
Wildfireacres burned (local data)0
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall: local data)119 records, 1996 to 2026 (119 zone-level)No damage reported in 119 records.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 and lightning.

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: 15 declarations covering 12 separate hazard incidents counted in this packet (declarations for the same incident count once; non-natural and evacuation-only declarations are not counted).

Federal disaster declarations for this county

Sources: 1, 2, 3

DeclaredIncident beganFEMA numberTypeTitleMapped hazardCounty Public Assistancefederal share obligated, nominal dollarsFlagsNotes
2024-06-282024-06-16DR-4797-MNMajor disasterSevere Storms and FloodingInland Flooding$393,308.18new since last plan; within last 5 years
2020-04-072020-01-20DR-4531-MNMajor disasterCOVID-19 PandemicNon-natural, not counted$38,228.27in the 12 months before plan approval
2020-03-132020-01-20EM-3453-MNEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedin the 12 months before plan approvalsame incident as DR-4531
2019-06-122019-03-12DR-4442-MNMajor disasterSevere Winter Storm, Straight-Line Winds, and FloodingInland Flooding (primary); also designated: Strong Wind, Winter Weather$605,891.06
2018-09-052018-06-15DR-4390-MNMajor disasterSevere Storms, Tornadoes, Straight-Line Winds, and FloodingInland Flooding (primary); also designated: Strong Wind, Tornado$414,885.77
2014-07-212014-06-11DR-4182-MNMajor disasterSevere Storms, Straight-Line Winds, Flooding, Landslides, and MudslidesInland Flooding (primary); also designated: Landslide, Strong Wind$253,761.46
2010-10-132010-09-22DR-1941-MNMajor disasterSevere Storms and FloodingInland Flooding$708,354.47
2005-09-132005-08-29EM-3242-MNEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedno Public Assistance recorded
2004-10-072004-09-14DR-1569-MNMajor disasterSevere Storms and FloodingInland Flooding$399,488.31
1997-01-161997-01-03DR-1158-MNMajor disasterSevere Winter StormsWinter Weatherno Public Assistance recorded
1993-06-111993-05-06DR-993-MNMajor disasterSevere Storms, Tornadoes & FloodingInland Flooding; Tornadono Public Assistance recorded
1991-12-261991-10-31DR-929-MNMajor disasterIce StormIce Stormno Public Assistance recorded
1976-06-171976-06-17EM-3013-MNEmergencyDroughtDroughtno Public Assistance recorded
1969-04-181969-04-18DR-255-MNMajor disasterFloodingInland Floodingno Public Assistance recorded
1965-04-111965-04-11DR-188-MNMajor disasterFloodingInland Floodingno 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

DeclaredIncident beganFEMA numberTypeTitleMapped hazard
1957-06-221957-06-22DR-80-MNMajor disasterFloodsInland Flooding

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.

7 Fire Management declarations (1976-09-08 to 1976-10-01) FEMA filed as Statewide with no county; each names one local fire. Listed on the state page.

Public Assistance not placed in any Minnesota county: 14 rows, $9,133,931.59; listed on the Minnesota state page.

Source: 3

Previous occurrences by hazard, with explicit no-event rows

Sources: 2, 6, 7

HazardStorm Events records, all years on file(years in the Period column)Since plan approvalrecordsIn the 12 months before plan approvalrecordsLast 5 yearsrecordsDeclared incidents, all yearsseparate disastersDeclared since approvalseparate disastersPeriodStatement
Cold Wave30816001996 to 2026-06-30Includes 1 Frost/Freeze record.
Drought0000101996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail14015412001955 to 2026-06-30
Heat Wave11202001996 to 2026-06-30
Hurricane0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Ice Storm3101101996 to 2026-06-30
Inland Flooding22101911996 to 2026-06-30
Landslide0000101996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Lightning1000001996 to 2026-06-30
Strong Wind16017016301955 to 2026-06-30Includes 17 High Wind records.
Tornado23202201950 to 2026-06-30
Wildfire0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Winter Weather11925523201996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationWhy listed
2018-09-20TornadoEF1, 5.3 mi within this county, 220 yd wide$1,500,000 property; $0 crops (2018 dollars)0, 0GRANADAB1-c most damaging: Tornado
2015-06-22High Wind61 kt (70 mph) estimated gust$100,000 property; $0 crops (zone total, 2015 dollars)0, 0NWS zone MNZ091 (MARTIN), zone-levelB1-c most damaging: High Wind and Strong Wind
2014-04-06Lightning$45,000 property; $0 crops (2014 dollars)0, 0FAIRMONT ARPTB1-c worst recorded: Lightning
2012-04-10Frost/Freeze$0 property; $20,000 crops (zone total, 2012 dollars)0, 0NWS zone MNZ091 (MARTIN), zone-levelB1-c worst recorded: Frost/Freeze
2004-09-15Flood$570,000 property; $3,700,000 crops (zone total, 2004 dollars)0, 0NWS zone MNZ091 (MARTIN), zone-levelB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
2001-08-04Heatdamage not reported0, 0NWS zone MNZ091 (MARTIN), zone-levelB1-c worst recorded: Excessive Heat, Heat
2001-04-07High Wind69 kt (79 mph) measureddamage not reported0, 0NWS zone MNZ091 (MARTIN), zone-levelB1-c worst recorded: High Wind and Strong Wind
1998-05-15Thunderstorm Wind55 kt (63 mph), measurement type not recorded$1,000,000 property; crops not reported (1998 dollars)0, 0FAIRMONTB1-c most damaging: Thunderstorm Wind
1996-01-31Cold/Wind Chilldamage not reported0, 0NWS zone MNZ091 (MARTIN), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
1975-05-22Thunderstorm Wind85 kt (98 mph), measurement type not recordeddamage not recorded (pre-1996 record)0, 0location not recordedB1-c worst recorded: Thunderstorm Wind
1965-05-06Hail3 indamage not recorded (pre-1996 record)0, 0location not recordedB1-c worst recorded: Hail
1951-06-25TornadoF2, 14.2 mi path length (whole path, pre-1996), 33 yd wide$250,000 property; crops not recorded (1951 dollars)0, 0location not recordedB1-c worst recorded: Tornado

The full list is in the Excel file, sheet "B1-d Storm Events history" (509 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

HazardFEMA annualized frequency (modeled)unit per rowUnitIn plain termsDescriptorDescriptor basisNRI events or days in its record period (hail, wind and tornado are area-weighted, so can be fractional)NRI periodLocationNote
Cold Wave11.1event-days per yearabout 11.1 days per yearLikelyStorm Events event-days in 16 of 30 years, 1996 to 2025 (53.3%)2102005-11-12 to 2024-11-12 (19 years)countywide
Drought12.2event-days per yearabout 12.2 days per yearStorm Events event-days in 0 of 30 years, 1996 to 2025 (0%)3362000 to 2025 (25.25 years; D3 and D4 only)countywideNo Storm Events drought record, 1996 to 2025
Earthquake0.000384annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.0384%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail4.39events per yearabout 4.39 per yearHighly likelyFEMA annualized frequency (modeled)166.9 (modeled)1986 to 2023 (38 years)countywide
Heat Wave4.79event-days per yearabout 4.79 days per yearLikelyStorm Events event-days in 8 of 30 years, 1996 to 2025 (26.7%)762005-11-12 to 2024-11-12 (19 years)countywide
Hurricaneevents per year1851 to 2024 (Atlantic)see B1-fNot Applicable in NRI for this county; no descriptor.
Ice Storm0.566event-days per yearabout 0.566 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)381946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding0.607event-days per yearabout 0.607 days per yearLikelyStorm Events event-days in 10 of 30 years, 1996 to 2025 (33.3%)171996 to 2023 (28 years)see B1-f
Landslide0.0788events per year (modeled)about 1 in 13 yearsPossibleFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning38.7days per year with a strikeabout 38.7 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind3.54events per yearabout 3.54 per yearHighly likelyFEMA annualized frequency (modeled)1351986 to 2023 (38 years)countywide
Tornado0.572events per yearabout 0.57 per yearLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Wildfire0.000112annual probability at a locationchance a given location in the county burns in a year: 0.0112%Storm Events records in 0 of 30 years, 1996 to 2025 (0%)not shownmodeledsee B1-fNo descriptor: no Storm Events record 1996 to 2025
Winter Weather21.7event-days per yearabout 21.7 days per yearHighly likelyStorm Events event-days in 29 of 30 years, 1996 to 2025 (96.7%)4122005-11-12 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

UnitDescriptorDefinition
events per yearHighly likely1 or more per year
events per yearLikelyabout once in 1 to 10 years
events per yearPossibleabout once in 10 to 100 years
events per yearUnlikelyless than once in 100 years
annual probabilityLikely10% to under 100% chance in a given year
annual probabilityPossible1% to under 10% chance in a given year
annual probabilityUnlikelyunder 1% chance in a given year
event-days (share of years)Highly likelyevent-days recorded in 90% or more of years
event-days (share of years)Likelyevent-days recorded in 10% to under 90% of years
event-days (share of years)Possibleevent-days recorded in some years but under 10% of years
lightning strike-daysHighly likelycloud-to-ground strikes on 1 or more days per year

Intensity bands: historical frequency (Storm Events)

Source: 6

HazardBandYearsEventscounty-coded recordsYears in periodEvents per yearevents / years
Hail1.00-1.99 in1996 to 202573302.43
Hail2.00 in+1996 to 20252300.0667
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 202590303
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 20251300.0333
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 20250300
TornadoEF0-11996 to 202510300.333
TornadoEF2-31996 to 20250300
TornadoEF4-51996 to 20250300
Tornadounrated (EFU)1996 to 20250300

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

HazardTractsrated of allNRI risk score, 0 to 100Tracts by rating
MinMedianMax
Cold Wave7 of 783.190.196.7Very High 3, Relatively High 4
Drought7 of 784.297.198.3Relatively High 1, Relatively Moderate 3, Relatively Low 3
Earthquake7 of 76.48.817.4Very Low 7
Hail7 of 776.797.398.6Very High 1, Relatively High 4, Relatively Moderate 2
Heat Wave7 of 727.636.167.6Relatively Moderate 2, Relatively Low 5
Hurricane0 of 7Not Applicable 7
Ice Storm7 of 754.066.481.5Relatively Moderate 2, Relatively Low 5
Inland Flooding7 of 726.756.973.6Relatively Moderate 6, Relatively Low 1
Landslide7 of 763.177.081.0Relatively Low 1, Very Low 6
Lightning7 of 731.336.564.5Relatively Moderate 3, Relatively Low 4
Strong Wind7 of 786.995.498.3Very High 2, Relatively High 5
Tornado7 of 775.481.597.3Very High 1, Relatively High 6
Wildfire7 of 754.065.569.8Relatively Low 1, Very Low 6
Winter Weather7 of 796.497.799.6Very High 7

Drought: Agriculture is all of NRI's expected annual loss for this hazard in the county, so the tract range mostly reflects where crop and livestock value is.

Hail: Agriculture is 82% of NRI's expected annual loss for this hazard in the county, so the tract range mostly reflects where crop and livestock value is.

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, drought, 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 (crop and livestock value where a line above names agriculture).

Each jurisdiction (starting figures from federal data)

Sources: 1, 3, 4, 6

JurisdictionTypePlan statusRepetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definitionPublic Assistance to this jurisdictionFEMA records matched by applicant name; federal share obligated, nominal dollarsEvent records naming this placeall years; since its planNotes
Martin CountyCountyExpired on 2025-09-27FMA RL 0, SRL 0; any 0$7,441.260 total; 0 since its planIncludes $7,441.26 for declarations not counted as hazard incidents (DR-4531-MN).
Ceylon cityCityExpired on 2025-09-27FMA RL 0, SRL 0; any 0no Public Assistance recorded15 total; 3 since its plan
Dunnell cityCityExpired on 2025-09-27$6,940.5711 total; 1 since its planNo NFIP community ID on this jurisdiction's plan row.
Fairmont cityCityExpired on 2025-09-27FMA RL 0, SRL 0; any 0$73,65164 total; 5 since its planIncludes $17,044.70 for declarations not counted as hazard incidents (DR-4531-MN).
Granada cityCityExpired on 2025-09-27FMA RL 0, SRL 0; any 0$51,366.779 total; 0 since its plan
Northrop cityCityExpired on 2025-09-27$41,095.498 total; 3 since its planNo NFIP community ID on this jurisdiction's plan row.
Ormsby cityCityPlan 108132 approved 2022-12-19, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0no Public Assistance recorded4 total; no approved plan
Sherburn cityCityExpired on 2025-09-27no Public Assistance recorded23 total; 3 since its planNo NFIP community ID on this jurisdiction's plan row.
Trimont cityCityExpired on 2025-09-27$38,081.7622 total; 4 since its planNo NFIP community ID on this jurisdiction's plan row. Includes $4,211.94 for declarations not counted as hazard incidents (DR-4531-MN).
Truman cityCityExpired on 2025-09-27FMA RL 0, SRL 0; any 0$136,988.3321 total; 1 since its plan
Welcome cityCityExpired on 2025-09-27FMA RL 0, SRL 0; any 0no Public Assistance recorded26 total; 6 since its plan

Repetitive-loss counts are for whole NFIP communities, which can extend beyond this county (see the note in B2-c).

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.

  • 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

HazardBuilding exposuremodeled dollarsAgriculture exposuremodeled dollarsPopulation exposedpeopleEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearCost of expected deaths and injuriesFEMA's dollar value per year, not property damageEAL as % of exposurebuildings; agriculture where notedStorm Events damage since 2020-09-28county-coded records, property plus crops, nominal dollarsZone-level damage since planproperty plus crops, reported for the zonePublic Assistance since plannominal dollars; see noteNote
Cold Wave$7,240,736,543$818,269,61120,025$1,727$402,956$1,955,596under 0.0001%$0
Droughtn/a$259,429,283n/an/a$1,017,476n/a0.392% (agriculture)NRI has no building exposure for this hazard; agriculture shown
Earthquake$12,907,608,908n/a20,025$11,425n/a$2,881under 0.0001%
Hail$7,240,736,543$818,269,61120,025$196,785$1,161,105$52,1760.00272%$0
Heat Wave$7,240,736,543$818,269,61120,025$6,598$12$222,886under 0.0001%$0
HurricaneNot Applicable in NRI for this county
Ice Storm$7,238,834,601n/a20,006$62,040n/a$4,7630.000857%$0
Inland Flooding$7,232,411,905$13,637,43192$4,240,262$57,343$1,587n/a (see note)$0$393,308.18NRI 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$35,978,037n/a116$45n/a$2950.000124%
Lightning$7,240,736,543n/a20,025$9,433n/a$54,4340.00013%
Strong Wind$7,240,736,543$818,269,61120,025$675,099$271,986$141,8900.00932%$0$0
Tornado$7,240,736,543$818,269,61120,025$1,513,954$19,678$646,3030.0209%$0
Wildfire$1,590,605,392$134,678,0533,855$5,329$162$3320.000335%
Winter Weather$7,240,736,543$818,269,61120,025$186,332$5,845$153,9120.00257%$0

Totals since 2020-09-28 (Storm Events through 2026-06-30): 32 county-coded records, 32 with a damage value recorded (including $0), $0; 39 zone-level records, 39 with a damage value recorded (including $0), $0 reported for the zone; Public Assistance: $393,308.18 on 1 counted declaration.

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

MeasureValue
Population20,025
Building value (total, not at risk)$7,240,736,543
Agriculture value (total, not at risk)$818,269,611
NRI risk rating (all hazards)Relatively Low
Expected annual loss, buildings and agriculture, all hazards$9,845,591
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)$3,237,054
Social vulnerability ratingRelatively Moderate
Community resilience ratingVery High
NRI versionDecember 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

DefinitionPropertiesSevere repetitive lossProperties
Repetitive loss, FMA definition (44 CFR 77.2)0Severe repetitive loss, FMA definition (44 CFR 77.2)0
Repetitive loss, NFIP insurance definition0Severe repetitive loss, NFIP insurance definition0

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

ScopeRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
County total0000000

Repeat-flood properties by jurisdiction in the plan (NFIP community)

Sources: 1, 4

JurisdictionNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
Martin County2706410000000
Ceylon city2702750000000
Fairmont city2702760000000
Granada city2702770000000
Ormsby city2709630000000
Truman city2702780000000
Welcome city2702790000000

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: 0 in every occupancy group.

Sources: 1, 4

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 0 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):

  1. FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-29T134039Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)
  2. FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-29T162832Z, pulled 2026-09-30, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)
  3. FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-29T150754Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)
  4. FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)
  5. 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)
  6. 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/
  7. 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
  8. 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). Martin County, MN: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 27091). Automated baseline. https://hazardplain.org/mn/27091/ 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]