Hazard Plain Automated baseline

Ravalli County, MT

Risk-assessment baseline packet

County FIPS:
30081
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 2029-11-20. Plan: Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263), approved 2024-11-21.

Since the plan was approved on 2024-11-21: 1 new hazard declaration (1 incident) and 44 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): Wildfire ($21,311,631 a year), Inland Flooding ($6,603,967) and Cold Wave ($5,524,533).

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 2029-11-20
Plan:
Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263)
Approved:
2024-11-21
Days to expiry:
1,147

What changed since your last plan (approved 2024-11-21)

New federal declarations:
1 new hazard declaration (1 incident): DR-4902-MT (Severe Winter Storm and Straight-Line Winds)
Storm Events records since approval:
44 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 0, SRL 0 (44 CFR 77.2); any definition: 1
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 expiryNotes
Ravalli CountyCountyApproved, expires 2029-11-20Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263)2024-11-212029-11-201,147this jurisdiction approved 2025-04-21
Darby townTownApproved, expires 2029-11-20Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263)2024-11-212029-11-201,147this jurisdiction approved 2025-11-17
Hamilton cityCityApproved, expires 2029-11-20Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263)2024-11-212029-11-201,147this jurisdiction approved 2025-11-17
Pinesdale townTownApproved, expires 2029-11-20Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263)2024-11-212029-11-201,147this jurisdiction approved 2025-11-19
Stevensville townTownApproved, expires 2029-11-20Western Montana Regional Hazard Mitigation Plan 2024 (FEMA plan 110263)2024-11-212029-11-201,147this jurisdiction approved 2025-11-17

Plan 110263 covers 51 other participants, named in the Excel file.

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
1WildfireRelatively HighRelatively High$20,311,559$1,201$998,870$21,311,6315
2Inland FloodingRelatively LowRelatively Low$6,518,514$268$85,185$6,603,96729
3Cold WaveRelatively ModerateRelatively High$16,251$121,173$5,387,110$5,524,53331Includes 11 Frost/Freeze records (outside NRI's Cold Wave definition; counted in this table and in B1-d, not in the B1-e descriptor).
4AvalancheRelatively HighRelatively Moderate$7,147n/a$1,175,628$1,182,7753
5EarthquakeRelatively LowRelatively Low$562,848n/a$147,664$710,512Storm Events does not record earthquakes.
6LightningRelatively ModerateRelatively Moderate$21,133n/a$372,740$393,8734
7Winter WeatherRelatively HighRelatively High$1,398$117$315,292$316,808366
8Heat WaveRelatively LowRelatively Low$71$2,868$303,945$306,8855
9Ice StormRelatively ModerateRelatively Moderate$185,402n/a$118,308$303,7105
10HailVery LowVery Low$87,638$6,306$11,841$105,78571
11Strong WindVery LowVery Low$37,979$3,650$54,768$96,397106Includes 43 High Wind and 27 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition).
12LandslideRelatively ModerateRelatively Low$16,355n/a$75,815$92,1713
13TornadoVery LowVery Low$19,529$28$31,863$51,4210No recorded events in Storm Events since 1996 (data through 2026-06-30).
14DroughtVery LowVery Lown/a$3,415n/a$3,4150No recorded events in Storm Events since 1996 (data through 2026-06-30).
HurricaneNot ApplicableNot Applicable0NRI rates hurricane Not Applicable for this county, and no counted federal declaration for this county names it (EM-3253-MT 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.

Not applicable to this county per NRI, with no federal declaration and no Storm Events record since 1996: 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
Avalanchetract 5.02 (Relatively Moderate, 86.6); tract 8 (Relatively Moderate, 84.8); tract 4.01 (Relatively Moderate, 84.5)
Earthquaketract 5.02 (Relatively Moderate, 83.9); tract 6.02 (Relatively Low, 73.7); tract 4.02 (Relatively Low, 69.9)
Hurricaneno tract has a National Risk Index rating for this hazard
Landslidetract 8 (Relatively High, 99.5); tract 7 (Relatively Moderate, 98.2); tract 6.01 (Relatively Moderate, 97.8)
Tornadotract 5.02 (Very Low, 21.1); tract 4.02 (Very Low, 18.4); tract 2.04 (Very Low, 13.0)
Wildfiretract 8 (Very High, 99.9); tract 7 (Very High, 99.7); tract 4.01 (Very High, 99.6)

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 5.02 is Census Tract 5.02). 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
Avalanchenone (count and damage only)3 records, 2010 to 2014 (3 zone-level)Avalanche, 2014-02-28, $319,000 property; $0 crops (2014 dollars), 1 direct death, 2 direct injuries (reported for the zone); NWS zone MTZ005Countywide (zone-level records).
Cold/Wind Chill, Extreme Cold/Wind Chillwind chill20 records, 1996 to 2025 (20 zone-level)1 day to 4 days (median 2 days); 17 with a recorded value4 consecutive days, 2023-02-21 to 2023-02-24, zone-levelCountywide (zone-level records).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage11 records, 2014 to 2026 (11 zone-level)Frost/Freeze, 2014-09-12, $50,000 crop damage (2014 dollars); NWS zone MTZ005Countywide (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)85 records, 1975 to 20220.75 in to 2.75 in (median 1 in); 84 with a recorded value2.75 in hail, 1988-06-28; same size also recorded on 1988-06-28Hail, 2002-08-04, $2,000,000 property; $100,000 crops (2002 dollars)Event records naming jurisdictions in the plan: Darby town (9 records), Hamilton city (9 records), Stevensville town (8 records).
Excessive Heat, Heatheat index (in event narratives)5 records, 2018 to 2024 (5 zone-level)2 days to 6 days (median 3 days); 4 with a recorded value6 consecutive days, 2024-07-19 to 2024-07-24, 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)5 records, 1997 to 2025 (5 zone-level)No damage reported in 5 records.Countywide (zone-level records).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)29 records, 1996 to 2021 (7 zone-level)Flood, 1996-03-11, $1,300,000 property; crops not reported (1996 dollars); NWS zone MTZ005Event records naming jurisdictions in the plan: Darby town (1 record), Hamilton city (1 record), Pinesdale town (1 record), Stevensville town (1 record). Zone-level records (7) 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)3 records, 2025Debris Flow, 2025-08-16, $10,000 property; $0 crops (2025 dollars)No event record names a jurisdiction in the plan.
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)4 records, 2010 to 2023Lightning, 2010-05-27, $250,000 property; $0 crops (2010 dollars)Event records naming jurisdictions in the plan: Darby town (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)70 records, 1996 to 2026 (70 zone-level)38 kt (44 mph) to 109 kt (125 mph) (median 51 kt (59 mph)); 69 with a recorded value109 kt (125 mph) measured gust, High Wind, 2021-01-13; NWS zone MTZ006Strong Wind, 2021-12-23, $1,000,000 property; $0 crops (zone total, 2021 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)52 records, 1968 to 202534 kt (39 mph) to 63 kt (72 mph) (median 52 kt (60 mph)); 42 with a recorded value63 kt (72 mph) measured gust, Thunderstorm Wind, 2024-08-23Thunderstorm Wind, 2024-07-24, $25,000 property; $0 crops (2024 dollars)Event records naming jurisdictions in the plan: Stevensville town (11 records), Hamilton city (9 records), Darby town (2 records).
TornadoEnhanced Fujita (Fujita before Feb 2007)3 records, 1975 to 1990F/EF0 to F/EF2 (median F/EF0); 3 with a recorded valueF2 tornado, 1975-06-23, 33 yd wide, $25,000 property; crops not recorded (1975 dollars), 1 direct injuryNo event record names a jurisdiction in the plan.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)5 records, 2000 to 2023 (3 zone-level)Wildfire, 2023-07-30, $300,000 property; $0 crops (2023 dollars); NWS zone MTZ005No event record names a jurisdiction in the plan. Zone-level records (3) apply countywide.
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall: local data)366 records, 1996 to 2026 (366 zone-level)Heavy Snow, 2001-06-04, $750,000 property; crops not reported (2001 dollars); NWS zone MTZ005Countywide (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 avalanche, 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: 13 declarations covering 9 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
2026-04-072025-12-17DR-4902-MTMajor disasterSevere Winter Storm and Straight-Line WindsStrong Wind (primary); also designated: Winter Weather$283,791.60new since last plan; within last 5 years
2020-03-312020-01-20DR-4508-MTMajor disasterCOVID-19 PandemicNon-natural, not counted$228,268.70
2020-03-132020-01-20EM-3476-MTEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedsame incident as DR-4508
2017-08-172017-08-17FM-5197-MTFire managementLolo Peak FireWildfireno Public Assistance recorded
2016-08-012016-08-01FM-5143-MTFire managementRoaring Lion FireWildfireno Public Assistance recorded
2014-04-172014-03-01DR-4172-MTMajor disasterIce Jams and FloodingInland Flooding$335,027.60
2012-09-112012-09-10FM-5016-MTFire managementSawtooth FireWildfireno Public Assistance recorded
2011-06-172011-04-04DR-1996-MTMajor disasterSevere Storms and FloodingInland Flooding$11,091.37
2005-09-132005-08-29EM-3253-MTEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedno Public Assistance recorded
2000-08-302000-07-13DR-1340-MTMajor disasterWildfiresWildfirePA not declared for this county
2000-08-052000-08-05FM-2317-MTFire managementMt-Southwestern Zone Two Fire ComplexWildfireno Public Assistance recordedsame incident as DR-1340
1997-07-251997-03-01DR-1183-MTMajor disasterSevere Storms,Ice Jams, Snow Melt, FloodingInland Floodingno Public Assistance recorded
1996-02-231996-02-04DR-1105-MTMajor disasterSevere Storms, Flooding, and Ice JamsInland 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
1964-12-181964-12-18DR-182-MTMajor disasterSevere Winter StormWinter Weather
1964-06-091964-06-09DR-172-MTMajor disasterHeavy Rains & FloodingInland Flooding
1953-06-061953-06-06DR-5-MTMajor 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.

11 Fire Management declarations (1973-08-16 to 1996-09-06) FEMA filed as Statewide with no county; each names one local fire. Listed on the state page.

Public Assistance not placed in any Montana county: 2 rows, $679,475.72; listed on the Montana 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
Avalanche3000001996 to 2026-06-30
Cold Wave31519001996 to 2026-06-30Includes 11 Frost/Freeze records.
Drought0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail85008001955 to 2026-06-30
Heat Wave5034001996 to 2026-06-30
Hurricane0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Ice Storm5202001996 to 2026-06-30
Inland Flooding29000401996 to 2026-06-30
Landslide3303001996 to 2026-06-30
Lightning4001001996 to 2026-06-30
Strong Wind12281025111955 to 2026-06-30Includes 43 High Wind and 27 Strong Wind records.
Tornado3000001950 to 2026-06-30
Wildfire5001401996 to 2026-06-30
Winter Weather36626970111996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationFlagsWhy listed
2024-07-19Excessive Heat$0 property; $0 crops (zone total, 2024 dollars)0, 0NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-levelin the 12 months before plan approval; within last 5 yearsB1-c worst recorded: Excessive Heat, Heat
2023-07-30Wildfire$300,000 property; $0 crops (zone total, 2023 dollars)0, 0NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-levelwithin last 5 yearsB1-c worst recorded: Wildfire
2023-02-21Cold/Wind Chill$0 property; $0 crops (zone total, 2023 dollars)0, 0NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-levelwithin last 5 yearsB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2021-01-13High Wind109 kt (125 mph) measured gust$2,000 property; $0 crops (zone total, 2021 dollars)0, 0NWS zone MTZ006 (BITTERROOT / SAPPHIRE MOUNTAINS), zone-levelB1-c worst recorded: High Wind and Strong Wind
2014-09-12Frost/Freeze$0 property; $50,000 crops (zone total, 2014 dollars)0, 0NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-levelB1-c worst recorded: Frost/Freeze
2014-02-28Avalanche$319,000 property; $0 crops (zone total, 2014 dollars)1, 2NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-leveldeaths or injuries recorded
2010-12-29Avalanche$0 property; $0 crops (zone total, 2010 dollars)1, 1NWS zone MTZ006 (BITTERROOT / SAPPHIRE MOUNTAINS), zone-leveldeaths or injuries recorded
2010-05-27Lightning$250,000 property; $0 crops (2010 dollars)0, 0CORVALLISB1-c worst recorded: Lightning
2001-06-04Heavy Snow$750,000 property; crops not reported (zone total, 2001 dollars)0, 0NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-levelB1-c worst recorded: Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet
1997-11-19Ice Stormdamage not reported2, 0NWS zone MTZ005 (SC MISSOULA/C&NC RAVALLI), zone-leveldeaths or injuries recorded
1996-03-11Flood$1,300,000 property; crops not reported (zone total, 1996 dollars)0, 0NWS zone MTZ005 (MISSOULA / BITTERROOT VALLEYS), zone-levelB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
1988-06-28Hail2.75 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" (661 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
Avalanche0.167events per yearabout 1 in 6 yearsLikelyFEMA annualized frequency (modeled)51994 to 2023 (30 years)see B1-f
Cold Wave2.18event-days per yearabout 2.18 days per yearLikelyStorm Events event-days in 13 of 30 years, 1996 to 2025 (43.3%)41.52005-11-12 to 2024-11-12 (19 years)countywide
Drought34event-days per yearabout 34 days per yearStorm Events event-days in 0 of 30 years, 1996 to 2025 (0%)1,2252000 to 2025 (25.25 years; D3 and D4 only)countywideNo Storm Events drought record, 1996 to 2025
Earthquake0.00446annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.446%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail0.363events per yearabout 1 in 3 yearsLikelyFEMA annualized frequency (modeled)13.8 (modeled)1986 to 2023 (38 years)countywide
Heat Wave0.741event-days per yearabout 0.741 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)12.12005-11-12 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 Storm0.121event-days per yearabout 0.121 days per yearLikelyStorm Events event-days in 4 of 30 years, 1996 to 2025 (13.3%)81946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding0.786event-days per yearabout 0.786 days per yearLikelyStorm Events event-days in 12 of 30 years, 1996 to 2025 (40%)221996 to 2023 (28 years)see B1-f
Landslide1.55events per year (modeled)about 1.55 per yearHighly likelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning26.8days per year with a strikeabout 26.8 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind0.198events per yearabout 1 in 5 yearsLikelyFEMA annualized frequency (modeled)81986 to 2023 (38 years)countywide
Tornado0.0341events per yearabout 1 in 29 yearsPossibleFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Wildfire0.0128annual probability at a locationchance a given location in the county burns in a year: 1.28%LikelyStorm Events records in 5 of 30 years, 1996 to 2025 (16.7%)not shownmodeledsee B1-f
Winter Weather53event-days per yearabout 53 days per yearHighly likelyStorm Events event-days in 30 of 30 years, 1996 to 2025 (100%)1,0072005-11-12 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 202546301.53
Hail2.00 in+1996 to 20250300
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 202530301
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 20250300
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 20256300.2
TornadoEF0-11996 to 20250300
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
Avalanche11 of 1380.582.586.6Relatively Moderate 11, Not Applicable 2
Cold Wave13 of 1376.294.598.6Very High 6, Relatively High 6, Relatively Moderate 1
Drought11 of 1369.574.079.6Relatively Low 2, Very Low 9, No Rating 2
Earthquake13 of 1323.556.283.9Relatively Moderate 1, Relatively Low 7, Very Low 5
Hail13 of 1336.451.669.4Relatively Low 12, Very Low 1
Heat Wave13 of 138.436.259.9Relatively Moderate 2, Relatively Low 9, Very Low 2
Hurricane0 of 13Not Applicable 13
Ice Storm13 of 1318.086.495.0Relatively High 4, Relatively Moderate 7, Relatively Low 1, Very Low 1
Inland Flooding13 of 137.248.784.4Relatively High 1, Relatively Moderate 6, Relatively Low 4, Very Low 2
Landslide13 of 1353.595.999.5Relatively High 1, Relatively Moderate 6, Relatively Low 4, Very Low 2
Lightning13 of 1350.081.895.3Relatively High 7, Relatively Moderate 6
Strong Wind13 of 1316.228.149.5Relatively Low 12, Very Low 1
Tornado13 of 133.810.621.1Very Low 13
Wildfire13 of 1397.999.499.9Very High 10, Relatively High 3
Winter Weather13 of 1379.694.998.4Very High 6, Relatively 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.

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 plan
Ravalli CountyCountyApproved, expires 2029-11-20FMA RL 0, SRL 0; any 1$348,456.380 total; 0 since its plan
Darby townTownApproved, expires 2029-11-20FMA RL 0, SRL 0; any 0no Public Assistance recorded14 total; 0 since its plan
Hamilton cityCityApproved, expires 2029-11-20FMA RL 0, SRL 0; any 0$37,643.9419 total; 0 since its plan
Pinesdale townTownApproved, expires 2029-11-20FMA RL 0, SRL 0; any 0no Public Assistance recorded1 total; 0 since its plan
Stevensville townTownApproved, expires 2029-11-20FMA RL 0, SRL 0; any 0no Public Assistance recorded20 total; 0 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 2024-11-21county-coded records, property plus crops, nominal dollarsZone-level damage since planproperty plus crops, reported for the zonePublic Assistance since plannominal dollars; see noteNote
Avalanche$1,715,467n/a10$7,147n/a$1,175,6280.417%
Cold Wave$10,206,797,094$54,920,69044,109$16,251$121,173$5,387,1100.000159%$10,000Storm Events damage since the plan includes 1 zone-level Frost/Freeze record ($10,000): outside NRI's Cold Wave definition.
Droughtn/a$11,399,604n/an/a$3,415n/a0.03% (agriculture)NRI has no building exposure for this hazard; agriculture shown
Earthquake$17,402,155,801n/a44,174$562,848n/a$147,6640.00323%
Hail$10,206,797,094$54,920,69044,109$87,638$6,306$11,8410.000859%
Heat Wave$10,206,797,094$54,920,69044,109$71$2,868$303,945under 0.0001%
HurricaneNot Applicable in NRI for this county
Ice Storm$10,189,447,614n/a44,042$185,402n/a$118,3080.00182%$0
Inland Flooding$10,201,172,279$3,229,460693$6,518,514$268$85,185n/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$324,557,356n/a1,341$16,355n/a$75,8150.00504%$15,500
Lightning$10,206,797,094n/a44,109$21,133n/a$372,7400.000207%
Strong Wind$10,206,797,094$54,920,69044,109$37,979$3,650$54,7680.000372%$500$318,000$283,791.60Storm Events damage since the plan includes 1 zone-level High Wind record ($307,000) and 4 zone-level Strong Wind records ($11,000): NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition.
Tornado$10,206,797,094$54,920,69044,109$19,529$28$31,8630.000191%
Wildfire$4,550,376,708$36,840,85727,472$20,311,559$1,201$998,8700.446%
Winter Weather$10,206,797,094$54,920,69044,109$1,398$117$315,292under 0.0001%$0$283,791.60

Totals since 2024-11-21 (Storm Events through 2026-06-30): 4 county-coded records, 4 with a damage value recorded (including $0), $16,000; 40 zone-level records, 31 with a damage value recorded (including $0), $328,000 reported for the zone; Public Assistance: $283,791.60 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
Population44,109
Building value (total, not at risk)$10,206,797,094
Agriculture value (total, not at risk)$54,920,690
NRI risk rating (all hazards)Relatively Low
Expected annual loss, buildings and agriculture, all hazards$27,924,853
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)$9,079,030
Social vulnerability ratingRelatively Moderate
Community resilience ratingRelatively Low
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 definition1Severe 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 total0010100
of which: Ravalli County (unincorporated area)0010100

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

Sources: 1, 4

JurisdictionNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
Ravalli County3000610010100
Darby town3000620000000
Hamilton city3001860000000
Pinesdale town3001880000000
Stevensville town3001810000000

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 residential0010100
2 to 4 unit residential0000000
other residential0000000
non-residential0000000
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 0 properties are FMA repetitive loss but not NFIP repetitive loss, and 1 property is 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). Ravalli County, MT: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 30081). Automated baseline. https://hazardplain.org/mt/30081/ 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]