Hazard Plain Automated baseline

Nelson County, ND

Risk-assessment baseline packet

County FIPS:
38063
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: Approved, expires 2027-02-07. Plan: Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098), approved 2022-02-08.

Since the plan was approved on 2022-02-08: 4 new hazard declarations (4 incidents) and 58 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): Cold Wave ($908,182 a year), Hail ($675,588) and Inland Flooding ($459,711).

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:
Approved, expires 2027-02-07
Plan:
Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)
Approved:
2022-02-08
Days to expiry:
130
Update underway:
none recorded in FEMA's plan tracker

What changed since your last plan (approved 2022-02-08)

New federal declarations:
4 new hazard declarations (4 incidents): DR-4660-ND (Severe Winter Storm and Flooding), DR-4686-ND (Severe Winter Storm, Snowstorm, and Straight-Line Winds), DR-4717-ND (Flooding), DR-4895-ND (Severe Storms, Straight-Line Winds, and Tornadoes)
Storm Events records since approval:
58 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 2, SRL 2 (44 CFR 77.2); any definition: 2
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 expiry
Nelson CountyCountyApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
Aneta cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
Lakota cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
McVille cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
Michigan City cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
Pekin cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
Petersburg cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130
Tolna cityCityApproved, expires 2027-02-07Nelson County, ND Hazard Mitigation Plan 2022 (FEMA plan 108098)2022-02-082027-02-07130

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
1Cold WaveRelatively LowRelatively Low$557$768,637$138,988$908,18289Includes 8 Frost/Freeze records (outside NRI's Cold Wave definition; counted in this table and in B1-d, not in the B1-e descriptor).
2HailRelatively ModerateRelatively Moderate$462,692$206,499$6,397$675,588159
3Inland FloodingVery LowVery Low$457,743$1,898$70$459,71159
4Ice StormRelatively ModerateRelatively Moderate$264,603n/a$17,915$282,5187
5Strong WindRelatively LowRelatively Low$46,627$138,461$17,525$202,613150Includes 32 High Wind records (a NOAA non-thunderstorm wind type, outside NRI's Strong Wind definition).
6TornadoVery LowVery Low$175,870$5,477$11,175$192,52131
7Winter WeatherRelatively ModerateRelatively Moderate$57,699$219$57,955$115,873146
8WildfireRelatively LowRelatively Low$103,838$149$2,488$106,4750Declared 1 time; no Storm Events record of this type.
9DroughtVery LowVery Lown/a$12,332n/a$12,3327
10LightningVery LowVery Low$1,450n/a$10,373$11,8240No recorded events in Storm Events since 1996 (data through 2026-06-30).
11Heat WaveVery LowVery Low$95under $1$8,616$8,7122
12EarthquakeVery LowVery Low$926n/a$230$1,156Storm Events does not record earthquakes.
13LandslideVery LowVery Low$5n/a$251$2560Declared 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-3247-ND 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, lightning 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.

NRI rating of the county's single census tract

Source: 5

HazardCensus tractNRI risk rating, score 0 to 100
Earthquaketract 9590 (Very Low, 8.4)
Hurricaneno tract has a National Risk Index rating for this hazard
Landslidetract 9590 (Relatively Low, 88.0)
Tornadotract 9590 (Relatively High, 81.5)
Wildfiretract 9590 (Relatively Moderate, 95.7)

A tract number is the Census tract number (for example 9590 is Census Tract 9590). 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 chill81 records, 1996 to 2026 (81 zone-level)1 day to 10 days (median 2 days); 64 with a recorded value10 consecutive days, 2021-02-06 to 2021-02-15, zone-levelCold/Wind Chill, 2003-03-08, $5,000 property; crops not reported (zone total, 2003 dollars)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 damage8 records, 2008 to 2026 (8 zone-level)No crop damage reported in 8 records.Countywide (zone-level records).
DroughtU.S. Drought Monitor scale (D0 to D4)7 records, 2006 to 2022 (7 zone-level)14 days to 114 days (median 36 days); 3 with a recorded value114 days (about 3.7 months), 2012-07-10 to 2012-10-31, a run of 4 consecutive Storm Events drought records, zone-levelCountywide (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.
EarthquakeModified Mercalli (local data)0Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hailhail size (inches)187 records, 1971 to 20250.75 in to 3 in (median 1 in); 187 with a recorded value3 in hail, 1988-08-16Hail, 1997-06-27, $10,000,000 property; crops not reported (1997 dollars)Event records naming jurisdictions in the plan: Lakota city (26 records), Petersburg city (20 records), Tolna city (20 records), Aneta city (17 records), Pekin city (15 records), Michigan City city (14 records).
Excessive Heat, Heatheat index (in event narratives)2 records, 2001 to 2011 (2 zone-level)2 days to 5 days (median 3.5 days); 2 with a recorded value5 consecutive days, 2011-07-16 to 2011-07-20, 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)7 records, 1996 to 2023 (7 zone-level)Ice Storm, 1997-04-04, $6,000,000 property; crops not reported (1997 dollars); NWS zone NDZ026Countywide (zone-level records).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)59 records, 1996 to 2019 (14 zone-level)Flash Flood, 2000-06-12, $2,000,000 property; $12,000,000 crops (2000 dollars)Event records naming jurisdictions in the plan: Pekin city (17 records), Lakota city (13 records), Michigan City city (3 records), Tolna city (3 records), Aneta city (2 records), Petersburg city (1 record). Zone-level records (14) 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)0Storm Events lists lightning with damage or casualties.
High Wind and Strong Wind (outside NRI's Strong Wind definition)wind speed (kt and mph)32 records, 1997 to 2024 (32 zone-level)35 kt (40 mph) to 66 kt (76 mph) (median 50 kt (58 mph)); 32 with a recorded value66 kt (76 mph), measurement type not recorded, High Wind, 1999-11-01; NWS zone NDZ026Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)139 records, 1971 to 202550 kt (58 mph) to 83 kt (96 mph) (median 58.5 kt (67 mph)); 118 with a recorded value83 kt (96 mph) estimated gust, Thunderstorm Wind, 2018-06-29Thunderstorm Wind, 2017-06-10, $60,000 property; crops not reported (2017 dollars)Event records naming jurisdictions in the plan: Pekin city (23 records), Michigan City city (17 records), Aneta city (13 records), Lakota city (13 records), Tolna city (13 records), Petersburg city (10 records).
TornadoEnhanced Fujita (Fujita before Feb 2007)41 records, 1976 to 2022F/EF0 to F/EF3 (median F/EF0); 41 with a recorded valueF3 tornado, 2001-07-18, 5 mi within this county, 150 yd wide, $200,000 property; crops not reported (2001 dollars)Tornado, 1987-07-21, $250,000 property; crops not recorded (1987 dollars)Event records naming jurisdictions in the plan: Tolna city (10 records), Aneta city (5 records), Michigan City city (4 records), Pekin city (3 records), Lakota city (2 records), Petersburg 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)146 records, 1996 to 2026 (146 zone-level)Blizzard, 1997-04-05, $6,000,000 property; crops not reported (1997 dollars); NWS zone NDZ026Countywide (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: 33 declarations covering 29 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
2025-10-222025-08-07DR-4895-NDMajor disasterSevere Storms, Straight-Line Winds, and TornadoesStrong Wind; Tornadono Public Assistance recordednew since last plan; within last 5 years
2023-07-052023-04-10DR-4717-NDMajor disasterFloodingInland Flooding$57,379.76new since last plan; within last 5 years
2023-02-052022-11-09DR-4686-NDMajor disasterSevere Winter Storm, Snowstorm, and Straight-Line WindsWinter Weather (primary); also designated: Strong Wind$8,967.76new since last plan; within last 5 years
2022-07-132022-04-22DR-4660-NDMajor disasterSevere Winter Storm and FloodingInland Flooding; Winter Weather$857,449.71new since last plan; within last 5 years
2020-10-022020-06-29DR-4565-NDMajor disasterSevere Storms and FloodingInland Flooding$138,456.28
2020-07-092020-04-01DR-4553-NDMajor disasterFloodingInland Flooding$234,033.12
2020-04-012020-01-20DR-4509-NDMajor disasterCOVID-19 PandemicNon-natural, not countedno Public Assistance recorded
2020-03-132020-01-20EM-3477-NDEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedsame incident as DR-4509
2020-01-212019-10-09DR-4475-NDMajor disasterFloodingInland Flooding$211,812.27
2013-07-122013-05-17DR-4128-NDMajor disasterSevere Storms and FloodingInland Flooding$399,836.02
2011-05-102011-02-14DR-1981-NDMajor disasterFloodingInland Flooding$881,205.26
2011-04-072011-04-05EM-3318-NDEmergencyFloodingInland Floodingno Public Assistance recorded
2010-04-302010-02-26DR-1907-NDMajor disasterFloodingInland Flooding$351,476.28
2010-03-142010-02-26EM-3309-NDEmergencyFloodingInland Flooding$810same incident as DR-1907
2009-03-242009-03-13DR-1829-NDMajor disasterSevere Storms and FloodingInland Flooding$613,092.34
2005-09-132005-08-29EM-3247-NDEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedno Public Assistance recorded
2005-07-222005-06-01DR-1597-NDMajor disasterSevere Storms, Flooding, and Ground SaturationInland Flooding$403,593.04
2004-05-052004-03-26DR-1515-NDMajor disasterSevere Storms, Flooding, and Ground SaturationInland Flooding$431,879.98
2001-05-282001-03-01DR-1376-NDMajor disasterSevere Storms, Flooding, & Ground SaturationInland Flooding$415,044.69
2000-06-272000-04-05DR-1334-NDMajor disasterSevere Storms, Flooding and Ground SaturationInland Flooding$336,862.58
1999-06-081999-03-01DR-1279-NDMajor disasterSevere Storms, Flooding, Snow, Ice, Ground Saturation, Lanslides, Mudslides, and TorInland Flooding (primary); also designated: Landslide, Tornado$327,113.13
1998-06-151998-03-02DR-1220-NDMajor disasterFlooding, Ground Saturation,Severe StormsInland Floodingno Public Assistance recorded
1997-04-071997-02-28DR-1174-NDMajor disasterSevere Flooding,Severe Winter Storms, Snowmelt, Spring RainsInland Flooding (primary); also designated: Wildfire, Winter Weatherno Public Assistance recorded
1997-01-121997-01-03DR-1157-NDMajor disasterSevere Winter Storms and Blizzard ConditionsWinter Weatherno Public Assistance recorded
1996-06-051996-03-12DR-1118-NDMajor disasterSevere Storms,Flooding, & Ice JamsInland Floodingno Public Assistance recorded
1995-05-161995-03-01DR-1050-NDMajor disasterSevere Storms, Flooding, and Ground SaturationInland Floodingno Public Assistance recorded
1994-07-011994-03-05DR-1032-NDMajor disasterSevere Storms, FloodingInland Floodingno Public Assistance recorded
1993-07-261993-06-22DR-1001-NDMajor disasterSevere Storms & FloodingInland Floodingno Public Assistance recorded
1979-04-261979-04-26DR-581-NDMajor disasterSevere Storms, Snowmelt & FloodingInland Floodingno Public Assistance recorded
1974-05-141974-05-14DR-434-NDMajor disasterHeavy Rains, Snowmelt & FloodingInland Floodingno Public Assistance recorded
1969-04-181969-04-18DR-256-NDMajor disasterFloodingInland Floodingno Public Assistance recorded
1966-03-231966-03-23DR-216-NDMajor disasterFloodingInland Floodingno Public Assistance recorded
1965-05-101965-05-10DR-195-NDMajor 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-79-NDMajor disasterTornadoTornado

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.

Public Assistance not placed in any North Dakota county: 1 row, $23,693.61; listed on the North Dakota 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 Wave89151124001996 to 2026-06-30Includes 8 Frost/Freeze records.
Drought7101001996 to 2026-06-30
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail187424001955 to 2026-06-30
Heat Wave2000001996 to 2026-06-30
Hurricane0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Ice Storm7101001996 to 2026-06-30
Inland Flooding590002621996 to 2026-06-30
Landslide0000101996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Lightning0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Strong Wind17119919221955 to 2026-06-30Includes 32 High Wind records.
Tornado41303211950 to 2026-06-30
Wildfire0000101996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Winter Weather14615823421996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationWhy listed
2021-02-06Extreme Cold/Wind Chill$0 property; $0 crops (zone total, 2021 dollars)0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2018-06-29Thunderstorm Wind83 kt (96 mph) estimated gustdamage not reported0, 0MC VILLEB1-c worst recorded: Thunderstorm Wind
2012-07-10Drought$0 property; crops not reported (zone total, 2012 dollars)0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c worst recorded: Drought
2011-07-16Excessive Heatdamage not reported0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c worst recorded: Excessive Heat, Heat
2003-03-08Cold/Wind Chill$5,000 property; crops not reported (zone total, 2003 dollars)0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c most damaging: Cold/Wind Chill, Extreme Cold/Wind Chill
2001-07-18TornadoF3, 5 mi within this county, 150 yd wide$200,000 property; crops not reported (2001 dollars)0, 0PEKINB1-c worst recorded: Tornado
2000-06-12Flash Flood$2,000,000 property; $12,000,000 crops (2000 dollars)0, 0PETERSBURGB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
1999-11-01High Wind66 kt (76 mph), measurement type not recorded$100,000 property; crops not reported (zone total, 1999 dollars)0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c worst recorded: High Wind and Strong Wind
1997-04-05Blizzard$6,000,000 property; crops not reported (zone total, 1997 dollars)0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c worst recorded: Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet
1997-04-04Ice Storm$6,000,000 property; crops not reported (zone total, 1997 dollars)0, 0NWS zone NDZ026 (NELSON), zone-levelB1-c worst recorded: Ice Storm
1996-12-20Blizzarddamage not reported0, 1NWS zone NDZ026 (NELSON), zone-leveldeaths or injuries recorded
1988-08-16Hail3 indamage not recorded (pre-1996 record)0, 0location not recordedB1-c worst recorded: Hail

The full list is in the Excel file, sheet "B1-d Storm Events history" (709 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 Wave22.8event-days per yearabout 22.8 days per yearLikelyStorm Events event-days in 24 of 30 years, 1996 to 2025 (80%)4342005-11-12 to 2024-11-12 (19 years)countywide
Drought9.98event-days per yearabout 9.98 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)2522000 to 2025 (25.25 years; D3 and D4 only)countywide
Earthquake0.000088annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.0088%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail3.7events per yearabout 3.7 per yearHighly likelyFEMA annualized frequency (modeled)140.7 (modeled)1986 to 2023 (38 years)countywide
Heat Wave1event-day per yearabout 1 day per yearPossibleStorm Events event-days in 2 of 30 years, 1996 to 2025 (6.67%)142005-11-12 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 Storm0.668event-days per yearabout 0.668 days per yearLikelyStorm Events event-days in 5 of 30 years, 1996 to 2025 (16.7%)451946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding2event-days per yearabout 2 days per yearLikelyStorm Events event-days in 13 of 30 years, 1996 to 2025 (43.3%)561996 to 2023 (28 years)see B1-f
Landslide0.0997events per year (modeled)about 1 in 10 yearsPossibleFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning27days per year with a strikeabout 27 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind2.06events per yearabout 2.06 per yearHighly likelyFEMA annualized frequency (modeled)791986 to 2023 (38 years)countywide
Tornado0.695events per yearabout 0.69 per yearLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Wildfire0.00114annual probability at a locationchance a given location in the county burns in a year: 0.114%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 Weather22.4event-days per yearabout 22.4 days per yearHighly likelyStorm Events event-days in 30 of 30 years, 1996 to 2025 (100%)4262005-11-12 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 202570302.33
Hail2.00 in+1996 to 20258300.267
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 202577302.57
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 202529300.967
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 202512300.4
TornadoEF0-11996 to 202529300.967
TornadoEF2-31996 to 20252300.0667
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

NRI risk score of the county's single census tract

Source: 5

HazardTract scoreNRI score, 0 to 100Rating
Cold Wave99.4Very High
Drought89.9Relatively Low
Earthquake8.4Very Low
Hail99.7Very High
Heat Wave16.2Very Low
HurricaneNot Applicable
Ice Storm99.8Very High
Inland Flooding53.5Relatively Moderate
Landslide88.0Relatively Low
Lightning60.6Relatively Moderate
Strong Wind98.6Very High
Tornado81.5Relatively High
Wildfire95.7Relatively Moderate
Winter Weather99.9Very High

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.

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 plan
Nelson CountyCountyApproved, expires 2027-02-07FMA RL 2, SRL 2; any 2$5,217,316.670 total; 0 since its plan
Aneta cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0$39,696.3037 total; 4 since its plan
Lakota cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0$44,236.9154 total; 1 since its plan
McVille cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
Michigan City cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0no Public Assistance recorded38 total; 1 since its plan
Pekin cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0$2,459.8258 total; 5 since its plan
Petersburg cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0$74,720.4532 total; 3 since its plan
Tolna cityCityApproved, expires 2027-02-07FMA RL 0, SRL 0; any 0$426.6946 total; 2 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 2022-02-08county-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$1,230,201,887$155,670,3483,007$557$768,637$138,988under 0.0001%$0
Droughtn/a$79,238,245n/an/a$12,332n/a0.0156% (agriculture)NRI has no building exposure for this hazard; agriculture shown
Earthquake$2,102,519,002n/a3,015$926n/a$230under 0.0001%
Hail$1,230,201,887$155,670,3483,007$462,692$206,499$6,3970.0376%
Heat Wave$1,230,201,887$155,670,3483,007$95under $1$8,616under 0.0001%
HurricaneNot Applicable in NRI for this county
Ice Storm$1,230,201,887n/a3,007$264,603n/a$17,9150.0215%
Inland Flooding$1,229,949,536$36,4633$457,743$1,898$70n/a (see note)$914,829.47NRI 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$3,124,961n/a6$5n/a$2510.000157%
Lightning$1,230,201,887n/a3,007$1,450n/a$10,3730.000118%
Strong Wind$1,230,201,887$155,670,3483,007$46,627$138,461$17,5250.00379%$0$8,967.76
Tornado$1,230,201,887$155,670,3483,007$175,870$5,477$11,1750.0143%$0no Public Assistance recorded (1 declaration)
Wildfire$340,178,370$49,078,856884$103,838$149$2,4880.0305%
Winter Weather$1,230,201,887$155,670,3483,007$57,699$219$57,9550.00469%$0$866,417.47

Totals since 2022-02-08 (Storm Events through 2026-06-30): 22 county-coded records, 1 with a damage value recorded (including $0), $0; 36 zone-level records, 4 with a damage value recorded (including $0), $0 reported for the zone; Public Assistance: $923,797.23 on 4 counted declarations, 3 of them with Public Assistance.

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
Population3,007
Building value (total, not at risk)$1,230,201,887
Agriculture value (total, not at risk)$155,670,348
NRI risk rating (all hazards)Very Low
Expected annual loss, buildings and agriculture, all hazards$2,705,779
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)$271,983
Social vulnerability ratingVery High
Community resilience ratingRelatively Moderate
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)2Severe repetitive loss, FMA definition (44 CFR 77.2)2
Repetitive loss, NFIP insurance definition1Severe repetitive loss, NFIP insurance definition1

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 total2211210
of which: Nelson County (unincorporated area)2211210

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

Sources: 1, 4

JurisdictionNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
Nelson County3806832211210
Aneta city3801550000000
Lakota city3800750000000
McVille city3802380000000
Michigan City city3800760000000
Pekin city3801720000000
Petersburg city3801940000000
Tolna city3802090000000

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 groupRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
single-family residential1100110
2 to 4 unit residential0000000
other residential0000000
non-residential1111100
not reported0000000

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 1 property is 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). Nelson County, ND: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 38063). Automated baseline. https://hazardplain.org/nd/38063/ 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]