Hazard Plain Automated baseline

Brown County, OH

Risk-assessment baseline packet

County FIPS:
39015
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 2028-04-17. Plan: Brown County Hazard Mitigation Plan (FEMA plan 109010), approved 2023-04-18.

Since the plan was approved on 2023-04-18: no new federal declaration.

NOAA Storm Events records since that date: 47 records (data through 2026-06-30).

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($12,502,003 a year), Tornado ($1,238,794) and Strong Wind ($1,209,116).

Repetitive-loss flood properties now: FMA RL 0, SRL 0 (44 CFR 77.2); any definition: 5.

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 2028-04-17
Plan:
Brown County Hazard Mitigation Plan (FEMA plan 109010)
Approved:
2023-04-18
Days to expiry:
565

What changed since your last plan (approved 2023-04-18)

New federal declarations:
none
Storm Events records since approval:
47 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 0, SRL 0 (44 CFR 77.2); any definition: 5
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
Brown CountyCountyApproved, expires 2028-04-17Brown County Hazard Mitigation Plan (FEMA plan 109010)2023-04-182028-04-17565this jurisdiction approved 2023-04-20
Aberdeen villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Fayetteville villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Georgetown villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Hamersville villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Mount Orab villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Ripley villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Russellville villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Sardinia villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleBrown County Hazard Mitigation Plan (FEMA plan 109010), pending adoption here2023-04-18 by FEMA; not yet adopted here2028-04-17 once adoptedFEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.

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 2026-06-30countStorm Events coverage note
1Inland FloodingRelatively ModerateRelatively Low$10,570,237$35,543$1,896,223$12,502,003111
2TornadoRelatively LowRelatively Low$866,110$665$372,019$1,238,79417
3Strong WindRelatively HighRelatively Moderate$278,483$1,387$929,246$1,209,116239Includes 10 High Wind and 2 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition).
4Cold WaveRelatively LowRelatively Low$1,305$55,054$603,117$659,4774Includes 1 Frost/Freeze record (outside NRI's Cold Wave definition; counted in this table and in B1-d, not in the B1-e descriptor).
5Heat WaveRelatively LowRelatively Low$4,539$2$559,354$563,8957
6EarthquakeRelatively LowRelatively Low$388,732n/a$101,443$490,175Storm Events does not record earthquakes.
7LightningRelatively ModerateRelatively Moderate$8,922n/a$463,050$471,9720No recorded events in Storm Events since 1996 (data through 2026-06-30).
8DroughtRelatively LowRelatively Lown/a$140,181n/a$140,1812
9HailRelatively LowRelatively Low$105,758$29,120$922$135,80054
10Ice StormRelatively ModerateRelatively Low$74,463n/a$54,861$129,3245
11WildfireVery LowVery Low$58,992$54$8,968$68,0140No recorded events in Storm Events since 1996 (data through 2026-06-30).
12Winter WeatherRelatively LowRelatively Low$25,039$346$27,231$52,615119
13LandslideRelatively LowRelatively Low$1,072n/a$24,716$25,7870Declared 3 times; no Storm Events record of this type.
14HurricaneVery LowVery Low$3,422$5,052$45$8,5200Declared 1 time; no Storm Events record of this type.

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 lightning, 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 9518 (Relatively Low, 75.0); tract 9513.01 (Relatively Low, 72.2); tract 9519 (Relatively Low, 67.0)
Hurricanetract 9515 (Very Low, 39.4); tract 9514 (Very Low, 37.5); tract 9519 (Very Low, 36.9)
Landslidetract 9516 (Relatively Moderate, 98.6); tract 9517 (Relatively Moderate, 97.6); tract 9519 (Relatively Low, 95.5)
Tornadotract 9518 (Relatively High, 79.7); tract 9519 (Relatively High, 75.2); tract 9513.01 (Relatively High, 74.5)
Wildfiretract 9515 (Relatively Moderate, 89.8); tract 9514 (Relatively Low, 85.6); tract 9519 (Relatively Low, 83.3)

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 9518 is Census Tract 9518). 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 chill3 records, 1996 to 2022 (3 zone-level)1 day to 5 days (median 3 days); 3 with a recorded value5 consecutive days, 1996-02-01 to 1996-02-05, zone-levelCountywide (zone-level records).Wind chill: in event narratives only (local data needed).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage1 record, 2007 (1 zone-level)Frost/Freeze, 2007-04-06, $540,000 crop damage (2007 dollars); NWS zone OHZ079Countywide (zone-level records).Temperature: in event narratives only (local data needed).
DroughtU.S. Drought Monitor scale (D0 to D4)2 records, 1999 (2 zone-level)62 days; 1 with a recorded value62 days (2 months), 1999-07-01 to 1999-08-31, a run of 2 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)66 records, 1968 to 20240.75 in to 2.75 in (median 0.88 in); 66 with a recorded value2.75 in hail, 1968-04-23Hail, 1994-04-12, $5,000 property; $50,000 crops (1994 dollars)Event records naming jurisdictions in the plan: Ripley village (7 records), Sardinia village (7 records), Georgetown village (6 records), Mount Orab village (5 records), Russellville village (3 records), Hamersville village (2 records), Aberdeen village (1 record), Fayetteville village (1 record).
Excessive Heat, Heatheat index (in event narratives)7 records, 1999 to 2023 (7 zone-level)1 day to 12 days (median 4 days); 5 with a recorded value12 consecutive days, 1999-07-20 to 1999-07-31, zone-levelCountywide (zone-level records).Heat index: in event narratives only (local data needed).
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, 1996 to 2022 (5 zone-level)No damage reported in 5 records.Countywide (zone-level records).Ice thickness: in event narratives only (local data needed).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)111 records, 1996 to 2025 (12 zone-level)Flash Flood, 2015-07-18, $3,000,000 property; $0 crops (2015 dollars), 3 direct deaths, 3 direct injuriesEvent records naming jurisdictions in the plan: Ripley village (9 records), Georgetown village (8 records), Fayetteville village (5 records), Hamersville village (4 records), Aberdeen village (2 records), Mount Orab village (2 records), Russellville village (2 records), Sardinia village (1 record). Zone-level records (12) 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)0Physical measure: in event narratives only (local data needed).
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)0Storm Events lists lightning with damage or casualties; physical measure in event narratives only (local data needed).
High Wind and Strong Wind (outside NRI's Strong Wind definition)wind speed (kt and mph)12 records, 2000 to 2024 (12 zone-level)43 kt (49 mph) to 58 kt (67 mph) (median 50 kt (58 mph)); 12 with a recorded value58 kt (67 mph) measured, High Wind, 2000-12-11; NWS zone OHZ079High Wind, 2008-09-14, $5,200,000 property; crops not reported, reported for the zone (2008 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)251 records, 1961 to 202545 kt (52 mph) to 87 kt (100 mph) (median 50 kt (58 mph)); 229 with a recorded value87 kt (100 mph) estimated gust, Thunderstorm Wind, 2011-04-20Thunderstorm Wind, 2023-03-03, $150,000 property; $0 crops (2023 dollars)Event records naming jurisdictions in the plan: Georgetown village (27 records), Mount Orab village (23 records), Fayetteville village (20 records), Ripley village (18 records), Sardinia village (15 records), Hamersville village (13 records), Aberdeen village (10 records), Russellville village (7 records).
TornadoEnhanced Fujita (Fujita before Feb 2007)27 records, 1961 to 2025F/EF0 to F/EF4 (median between F/EF0 and F/EF1); 26 with a recorded valueF4 tornado, 1968-04-23, 9.1 mi path length (whole path, pre-1996), 550 yd wide, $2,500,000 property; crops not recorded (1968 dollars), 1 direct death, 4 direct injuriesEvent records naming jurisdictions in the plan: Mount Orab village (2 records), Russellville village (2 records), Sardinia village (2 records), Fayetteville village (1 record), Hamersville village (1 record), Ripley village (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)0Acres burned: in event narratives only (local data needed).
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall: local data)119 records, 1996 to 2026 (119 zone-level)Winter Storm, 1996-01-06, $500,000 property; crops not reported (1996 dollars); NWS zone OHZ079Countywide (zone-level records).Snow depth: in event narratives only (local data needed).

Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records whose zone 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: 19 declarations covering 14 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 dollarsNotes
2020-03-312020-01-20DR-4507-OHMajor disasterCOVID-19 PandemicNon-natural, not countednone placed in this county by FEMA's record; $3,080,910.74 for this declaration is not placed in any county (see the state page)
2020-03-132020-01-20EM-3457-OHEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedsame incident as DR-4507
2019-04-082019-02-05DR-4424-OHMajor disasterSevere Storms, Flooding, and LandslidesInland Flooding (primary); also designated: Landslide$2,112,835.55
2018-04-172018-02-14DR-4360-OHMajor disasterSevere Storms, Landslides, and MudslidesInland Flooding (primary); also designated: Landslide$941,261.42
2012-06-302012-06-29EM-3346-OHEmergencySevere StormsHazard not mapped (severe storm title names no single hazard); not countedno Public Assistance recorded
2011-07-132011-04-04DR-4002-OHMajor disasterSevere Storms and FloodingInland Flooding$2,125,850.50
2008-10-242008-09-14DR-1805-OHMajor disasterSevere Wind Storm Associated with Tropical Depression IkeHurricane; Strong Wind$93,146.56
2008-04-242008-03-07EM-3286-OHEmergencyRecord Snow and Near Record SnowWinter Weather$89,319.55
2005-09-132005-08-29EM-3250-OHEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedno Public Assistance recorded
2005-02-152004-12-22DR-1580-OHMajor disasterSevere Winter Storms, Flooding, and MudslidesInland Flooding; Landslide; Winter Weather$354,076.45
2004-09-192004-08-27DR-1556-OHMajor disasterSevere Storms and FloodingInland Flooding: designated for Hazard Mitigation only (no Public or Individual Assistance for this county); not countedPA not declared for this county
2001-08-272001-07-17DR-1390-OHMajor disasterSevere Storms and FloodingInland Flooding$290,772.90
1997-03-041997-02-28DR-1164-OHMajor disasterSevere Storms and FloodingInland Floodingno Public Assistance recorded
1996-06-241996-05-02DR-1122-OHMajor disasterFloodingInland Floodingno Public Assistance recorded
1996-01-271996-01-20DR-1097-OHMajor disasterSevere Storms and FloodingInland FloodingPA not declared for this county
1978-01-261978-01-26EM-3055-OHEmergencyBlizzards & SnowstormsWinter Weatherno Public Assistance recorded
1977-02-021977-02-02EM-3029-OHEmergencySnowstormsWinter Weatherno Public Assistance recorded
1968-06-051968-06-05DR-243-OHMajor disasterHeavy Rains & FloodingInland Floodingno Public Assistance recorded
1968-05-041968-05-04DR-238-OHMajor disasterTornadoes & Severe StormsTornadono 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
1964-03-241964-03-24DR-167-OHMajor disasterSevere Storms & FloodingInland Flooding
1959-01-231959-01-23DR-90-OHMajor disasterFloodsInland Flooding
1956-05-171956-05-17DR-57-OHMajor disasterWind StormOther, not an NRI hazard; not counted

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 Ohio county: 1 row, $3,080,910.74; listed on the Ohio 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 Wave4011001996 to 2026-06-30Includes 1 Frost/Freeze record.
Drought2000001996 to 2026-06-30
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail66246001955 to 2026-06-30
Heat Wave7101001996 to 2026-06-30
Hurricane0000101996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Ice Storm5001001996 to 2026-06-30
Inland Flooding1119515901996 to 2026-06-30
Landslide0000301996 to 2026-06-30No Storm Events records of this type; 3 federal declared incidents (see declarations table)
Lightning0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Strong Wind263241742101955 to 2026-06-30Includes 10 High Wind and 2 Strong Wind records.
Tornado27123101950 to 2026-06-30
Wildfire0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Winter Weather11910214401996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationWhy listed
2015-07-18Flash Flood$3,000,000 property; $0 crops (2015 dollars)3, 3EASTWOOD to WHITE OAKdeaths or injuries recorded
2011-04-20Thunderstorm Wind87 kt (100 mph) estimated gust$15,000 property; $0 crops (2011 dollars)0, 0FIVEMILEB1-c worst recorded: Thunderstorm Wind
2008-09-14High Wind52 kt (60 mph) estimated gust$5,200,000 property; crops not reported, reported for the zone (2008 dollars)0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c most damaging: High Wind and Strong Wind
2007-04-06Frost/Freeze$0 property; $540,000 crops, reported for the zone (2007 dollars)0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c worst recorded: Frost/Freeze
2000-12-11High Wind58 kt (67 mph) measureddamage not reported0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c worst recorded: High Wind and Strong Wind
1999-07-20Heatdamage not reported0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c worst recorded: Excessive Heat, Heat
1999-07-01Droughtdamage not reported0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c worst recorded: Drought
1997-03-01Flash Flood$2,000,000 property; crops not reported (1997 dollars)1, 0COUNTYWIDEdeaths or injuries recorded
1996-02-01Cold/Wind Chill$20,000 property; crops not reported, reported for the zone (1996 dollars)0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
1996-01-06Winter Storm$500,000 property; crops not reported, reported for the zone (1996 dollars)0, 0NWS zone OHZ079 (BROWN), zone-levelB1-c worst recorded: Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet
1968-04-23Hail2.75 indamage not recorded (pre-1996 record)0, 0location not recordedB1-c worst recorded: Hail
1968-04-23TornadoF4, 9.1 mi path length (whole path, pre-1996), 550 yd wide$2,500,000 property; crops not recorded (1968 dollars)1, 4location not recordeddeaths or injuries recorded

The full list is in the Excel file, sheet "B1-d Storm Events history" (604 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).

FEMA's declaration data list no tribal or special-area declarations for this state.

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 Wave1.84event-days per yearabout 1.84 days per yearLikely (from Storm Events: 3 of 30 years)event-days in 3 of 30 years, 1996 to 2025 (10%)352005-11-12 to 2024-11-12 (19 years)countywide
Drought2.25event-days per yearabout 2.25 days per yearPossible (from Storm Events: 1 of 30 years)event-days in 1 of 30 years, 1996 to 2025 (3.33%)632000 to 2025 (25.25 years; D3 and D4 only)countywide
Earthquake0.00184annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.184%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail3.19events per yearabout 3.19 per yearHighly likelyFEMA annualized frequency (modeled)121.3 (modeled)1986 to 2023 (38 years)countywide
Heat Wave5.95event-days per yearabout 5.95 days per yearLikely (from Storm Events: 5 of 30 years)event-days in 5 of 30 years, 1996 to 2025 (16.7%)932005-11-12 to 2024-11-12 (19 years)countywide
Hurricane0.0105events per yearabout 1 in 95 yearsPossibleFEMA annualized frequency (modeled)61851 to 2024 (Atlantic)see B1-fNRI counts hurricane and tropical storm tracks passing within storm-force wind range; federal declarations are in B1-d.
Ice Storm0.866event-days per yearabout 0.866 days per yearLikely (from Storm Events: 5 of 30 years)event-days in 5 of 30 years, 1996 to 2025 (16.7%)591946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding2.5event-days per yearabout 2.5 days per yearHighly likely (from Storm Events: 28 of 30 years)event-days in 28 of 30 years, 1996 to 2025 (93.3%)701996 to 2023 (28 years)see B1-f
Landslide0.253events per year (modeled)about 1 in 4 yearsLikelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning49.5days per year with a strikeabout 49.5 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind2.7events per yearabout 2.7 per yearHighly likelyFEMA annualized frequency (modeled)1031986 to 2023 (38 years)countywide
Tornado0.26events per yearabout 1 in 4 yearsLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Wildfire0.000546annual probability at a locationchance a given location in the county burns in a year: 0.0546%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 Weather11.4event-days per yearabout 11.4 days per yearHighly likely (from Storm Events: 28 of 30 years)event-days in 28 of 30 years, 1996 to 2025 (93.3%)2162005-11-12 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 202516300.533
Hail2.00 in+1996 to 20251300.0333
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 2025204306.8
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 202510300.333
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 202513300.433
TornadoEF0-11996 to 202517300.567
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 Wave10 of 1045.961.471.3Relatively Moderate 9, Relatively Low 1
Drought10 of 1081.788.992.2Relatively Moderate 2, Relatively Low 8
Earthquake10 of 1046.463.575.0Relatively Low 10
Hail10 of 1049.565.172.1Relatively Moderate 3, Relatively Low 7
Heat Wave10 of 1050.667.279.9Relatively Moderate 8, Relatively Low 2
Hurricane10 of 1026.234.739.4Very Low 10
Ice Storm10 of 1064.678.687.7Relatively Moderate 8, Relatively Low 2
Inland Flooding10 of 1025.681.598.8Very High 2, Relatively High 5, Relatively Moderate 2, Relatively Low 1
Landslide10 of 1055.687.198.6Relatively Moderate 2, Relatively Low 4, Very Low 4
Lightning10 of 1081.593.097.6Very High 3, Relatively High 7
Strong Wind10 of 1088.795.097.6Very High 3, Relatively High 7
Tornado10 of 1054.965.579.7Relatively High 3, Relatively Moderate 7
Wildfire10 of 1063.380.489.8Relatively Moderate 1, Relatively Low 7, Very Low 2
Winter Weather10 of 1055.170.482.5Relatively High 2, Relatively Moderate 8

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
Brown CountyCountyApproved, expires 2028-04-17FMA RL 0, SRL 0; any 3$1,506.750 total; 0 since its plan
Aberdeen villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0$77,825.3013 total; no approved plan
Fayetteville villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0no Public Assistance recorded27 total; no approved plan
Georgetown villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0$87,441.1241 total; no approved plan
Hamersville villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0no Public Assistance recorded20 total; no approved plan
Mount Orab villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0$64,291.5132 total; no approved plan
Ripley villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 2no Public Assistance recorded35 total; no approved plan
Russellville villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0$65,779.1114 total; no approved plan
Sardinia villageVillagePlan 109010 approved 2023-04-18, pending adoption here; not yet eligibleFMA RL 0, SRL 0; any 0no Public Assistance recorded25 total; no approved 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 2023-04-18county-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$9,869,134,176$92,361,01943,652$1,305$55,054$603,117under 0.0001%
Droughtn/a$80,259,349n/an/a$140,181n/a0.175% (agriculture)NRI has no building exposure for this hazard; agriculture shown
Earthquake$16,665,168,262n/a43,676$388,732n/a$101,4430.00233%
Hail$9,869,139,956$92,361,01943,652$105,758$29,120$9220.00107%$0
Heat Wave$9,869,134,176$92,361,01943,652$4,539$2$559,354under 0.0001%
Hurricane$9,853,528,734$91,901,62843,590$3,422$5,052$45under 0.0001%
Ice Storm$9,866,043,603n/a43,639$74,463n/a$54,8610.000755%
Inland Flooding$9,841,112,516$1,731,7071,170$10,570,237$35,543$1,896,223n/a (see note)$95,000NRI 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$268,265,944n/a1,168$1,072n/a$24,7160.000399%
Lightning$9,869,139,956n/a43,652$8,922n/a$463,050under 0.0001%
Strong Wind$9,869,139,956$92,361,01943,652$278,483$1,387$929,2460.00282%$92,500
Tornado$9,869,139,956$92,361,01943,652$866,110$665$372,0190.00878%$15,000
Wildfire$1,570,711,037$14,777,67211,761$58,992$54$8,9680.00376%
Winter Weather$9,869,134,176$92,361,01943,652$25,039$346$27,2310.000254%

Totals since 2023-04-18 (Storm Events through 2026-06-30): 35 county-coded records, 35 with a damage value recorded (including $0), $202,500; 12 zone-level records, 0 with a damage value recorded (including $0), $0 reported for the zone; Public Assistance: no counted declaration since the plan.

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
Population43,652
Building value (total, not at risk)$9,869,139,956
Agriculture value (total, not at risk)$92,361,019
NRI risk rating (all hazards)Relatively Low
Expected annual loss, buildings and agriculture, all hazards$12,654,478
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)$5,041,195
Social vulnerability ratingRelatively 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)0Severe repetitive loss, FMA definition (44 CFR 77.2)0
Repetitive loss, NFIP insurance definition5Severe 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 and state-level rows

Sources: 1, 4

ScopeRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
County total0050501
of which: Brown County (unincorporated area)0030300
of which: Ripley village0020201
Statewide, no county in FEMA's file0010100

The statewide row counts properties FEMA's file gives with no county in this state; they are listed for reference and are not in this county's counts.

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

Sources: 1, 4

JurisdictionNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
Brown County3900340030300
Aberdeen village3906750000000
Fayetteville village3907880000000
Georgetown village3900350000000
Hamersville village3906760000000
Mount Orab village3906210000000
Ripley village3900360020201
Russellville village3909120000000
Sardinia village3907890000000

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 residential0040401
2 to 4 unit residential0000000
other residential0000000
non-residential0010100
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 5 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, organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B. Each section heading names the item its tables support; the plan and FEMA's review decide whether the 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). Brown County, OH: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 39015). Automated baseline. https://hazardplain.org/oh/39015/ 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]

Hazard Plain release 2026-10. As of 2026-09-30; Storm Events data through 2026-06-30. Automated baseline.