Hazard Plain Automated baseline

Mercer County, PA

Risk-assessment baseline packet

County FIPS:
42085
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: No county-level plan row in FEMA data.

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($29,059,608 a year), Tornado ($1,338,717) and Strong Wind ($980,505).

The tables that follow are organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B (B1-a to B2-c); each heading says which item its tables support.

Plan clock

No county-level plan row in FEMA data

What changed since your last plan

Not available. No county-level plan row in FEMA data, so there is no approval date to count from.

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

Plan status for every jurisdiction listed in this county: 48 rows, in the section "Plan clock: Plan status for every jurisdiction listed in this county" on the following pages.

State plan status and tribal plans in this state: see the state page.

Plan clock

Plan status for every jurisdiction listed in this county

Source: 1

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiryUpdate underwayNotes
Clark boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-04
Farrell cityCityApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-03-27
Fredonia boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Greenville boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Grove City boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progress
Hermitage cityCityApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-11
Jackson Center boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-06
Jamestown boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-11
Mercer boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-11
New Lebanon boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-03-28
Sandy Lake boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
Sharon cityCityApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
Sharpsville boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-12
Sheakleyville boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-05-18
Stoneboro boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-06-06
West Middlesex boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-12
Wheatland boroughOrganized BoroughApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-05-09
Coolspring townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
Deer Creek townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-08
Delaware townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
East Lackawannock townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Fairview townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
Findley townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
French Creek townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Greene townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
Hempfield townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-04
Jackson townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
Jefferson townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Lackawannock townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Lake townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-12
Liberty townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-13
Mill Creek townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
New Vernon townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-06-12
Otter Creek townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-16
Perry townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
Pine townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
Pymatuning townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-13
Salem townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
Sandy Creek townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
Sandy Lake townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-05
Shenango townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-20
South Pymatuning townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-12
Springfield townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-04
Sugar Grove townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-03
West Salem townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-11
Wilmington townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-12
Wolf Creek townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-10
Worth townshipTownshipApproved, expires 2028-03-19Mercer County Hazard Mitigation Plan (FEMA plan 108946)2023-03-202028-03-19536FEMA tracker shows a plan in progressthis jurisdiction approved 2023-04-12

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 Moderate$29,006,613$24,355$28,640$29,059,608105
2TornadoRelatively LowRelatively Low$980,065$2,310$356,343$1,338,71712
3Strong WindRelatively ModerateRelatively Moderate$522,702$2,699$455,104$980,505493Includes 22 High Wind and 2 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition).
4LightningRelatively HighRelatively High$9,514n/a$916,982$926,4960No recorded events in Storm Events since 1996 (data through 2026-06-30).
5HailRelatively ModerateRelatively Low$573,680$45,249$28,322$647,250149
6HurricaneRelatively LowRelatively Low$271,438$25,714$9,317$306,4690Declared 2 times; no Storm Events record of this type.
7EarthquakeVery LowVery Low$210,210n/a$58,336$268,546Storm Events does not record earthquakes.
8Cold WaveVery LowRelatively Low$1,219$18,244$235,637$255,1009
9Winter WeatherRelatively ModerateRelatively Moderate$136,943$43$31,086$168,07293
10Heat WaveVery LowVery Low$6$2,044$108,353$110,4030No recorded events in Storm Events since 1996 (data through 2026-06-30).
11Ice StormRelatively LowRelatively Low$23,751n/a$29,558$53,30910
12WildfireVery LowVery Low$16,481$11$2,197$18,6880No recorded events in Storm Events since 1996 (data through 2026-06-30).
13LandslideVery LowVery Low$241n/a$496$7370No recorded events in Storm Events since 1996 (data through 2026-06-30).
14DroughtNo RatingNo Expected Annual Lossesn/a$0n/a$02

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 331 (Relatively Low, 41.7); tract 330 (Very Low, 39.7); tract 329 (Very Low, 37.6)
Hurricanetract 318 (Relatively Low, 60.4); tract 326.01 (Relatively Low, 58.2); tract 331 (Relatively Low, 57.6)
Landslidetract 318 (Relatively Low, 84.5); tract 326.01 (Relatively Low, 84.2); tract 331 (Relatively Low, 83.1)
Tornadotract 326.01 (Relatively Moderate, 57.2); tract 318 (Relatively Moderate, 56.2); tract 331 (Relatively Moderate, 55.8)
Wildfiretract 320 (Relatively Low, 75.0); tract 326.01 (Relatively Low, 71.5); tract 331 (Relatively Low, 71.1)

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 331 is Census Tract 331). 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 chill9 records, 2009 to 2025 (9 zone-level)1 day to 3 days (median 2 days); 9 with a recorded value3 consecutive days, 2025-01-20 to 2025-01-22, zone-levelCountywide (zone-level records).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage0
DroughtU.S. Drought Monitor scale (D0 to D4)2 records, 1999 (2 zone-level)61 days; 1 with a recorded value61 days (2 months), 1999-08-01 to 1999-09-30, 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)160 records, 1956 to 20260.75 in to 2.75 in (median 1 in); 160 with a recorded value2.75 in hail, 2019-05-28Hail, 2022-06-16, $30,000 property; $0 crops (2022 dollars)Event records naming jurisdictions in the plan: Mercer borough (17 records), Grove City borough (16 records), Sandy Lake borough (11 records), Sandy Lake township (11 records), Sharon city (11 records), Greenville borough (10 records), Stoneboro borough (8 records), Farrell city (6 records), Hermitage city (5 records), Jackson Center borough (5 records); and 11 more jurisdictions (see the Excel file).
Excessive Heat, Heatheat index (in event narratives)0
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)10 records, 1997 to 2011 (10 zone-level)Ice Storm, 2005-01-05, $20,000 property; crops not reported (2005 dollars); NWS zone PAZ007Countywide (zone-level records).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)105 records, 1996 to 2025 (5 zone-level)Flash Flood, 2002-08-16, $250,000 property; crops not reported (2002 dollars)Event records naming jurisdictions in the plan: Greenville borough (15 records), Sharon city (13 records), Mercer borough (10 records), Jamestown borough (7 records), Farrell city (4 records), Stoneboro borough (4 records), Grove City borough (3 records), Sandy Lake borough (3 records), Sandy Lake township (3 records), Sharpsville borough (3 records); and 7 more jurisdictions (see the Excel file). Zone-level records (5) 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)24 records, 1996 to 2023 (24 zone-level)43 kt (49 mph) to 61 kt (70 mph) (median 50 kt (58 mph)); 21 with a recorded value61 kt (70 mph) estimated, High Wind, 2000-12-12; NWS zone PAZ007High Wind, 2008-09-14, $1,000,000 property; $0 crops (zone total, 2008 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)523 records, 1956 to 202648 kt (55 mph) to 130 kt (150 mph) (median 50 kt (58 mph)); 419 with a recorded value130 kt (150 mph), measurement type not recorded, Thunderstorm Wind, 1995-05-24Thunderstorm Wind, 2024-10-06, $1,000,000 property; $0 crops (2024 dollars)Event records naming jurisdictions in the plan: Mercer borough (43 records), Grove City borough (39 records), Greenville borough (36 records), Hermitage city (25 records), Sharon city (25 records), Farrell city (23 records), Jamestown borough (23 records), Sandy Lake borough (21 records), Sandy Lake township (21 records), Sharpsville borough (20 records); and 12 more jurisdictions (see the Excel file).
TornadoEnhanced Fujita (Fujita before Feb 2007)25 records, 1954 to 2024F/EF0 to F/EF5 (median F/EF1); 21 with a recorded valueF5 tornado, 1985-05-31, 12 mi path length (whole path, pre-1996), 450 yd wide, $250,000 property; crops not recorded (1985 dollars), 8 direct deaths, 60 direct injuriesTornado, 1985-05-31, $25,000,000 property; crops not recorded (1985 dollars)Event records naming jurisdictions in the plan: Mercer borough (4 records), New Lebanon borough (2 records), Sharon city (2 records), Farrell city (1 record), Sandy Lake borough (1 record), Sandy Lake township (1 record), Sharpsville borough (1 record), Shenango township (1 record), Stoneboro borough (1 record), Wheatland borough (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)93 records, 1996 to 2026 (93 zone-level)Heavy Snow, 2004-12-20, $650,000 property; crops not reported (2004 dollars), 100 direct injuries (reported for the zone); NWS zone PAZ007Countywide (zone-level records).

Where a hazard names more than 10 jurisdictions, the table lists the 10 with the most records; every one is in the Excel file, sheet "B1-c Extent".

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: 13 declarations covering 8 separate hazard incidents counted in this packet (declarations for the same incident count once; non-natural and evacuation-only declarations are not counted).

No county-level plan row in FEMA data, so there is no approval date to count from.

Federal disaster declarations for this county

Sources: 1, 2, 3

DeclaredIncident beganFEMA numberTypeTitleMapped hazardCounty Public Assistancefederal share obligated, nominal dollarsNotes
2020-03-302020-01-20DR-4506-PAMajor disasterCOVID-19 PandemicNon-natural, not counted$5,794,694.67
2020-03-132020-01-20EM-3441-PAEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedsame incident as DR-4506
2012-10-292012-10-26EM-3356-PAEmergencyHurricane SandyHurricaneno Public Assistance recorded
2005-09-102005-08-29EM-3235-PAEmergencyHurricane KatrinaHurricane: evacuation support, not a local hazard event; not countedno Public Assistance recorded
2004-09-192004-09-17DR-1557-PAMajor disasterTropical Depression IvanHurricane: designated for Hazard Mitigation only (no Public or Individual Assistance for this county); not countedPA not declared for this county
2004-09-192004-09-08DR-1555-PAMajor disasterSevere Storms and Flooding Associated with Tropical Depression FrancesHurricane; Inland Flooding: designated for Hazard Mitigation only (no Public or Individual Assistance for this county); not countedPA not declared for this county
2003-08-232003-07-21DR-1485-PAMajor disasterSevere Storms, Tornadoes, and FloodingInland Flooding; Tornado$1,050,390.42
1996-01-211996-01-19DR-1093-PAMajor disasterSevere Storms and FloodingInland FloodingPA not declared for this county
1993-03-161993-03-13EM-3105-PAEmergencySevere Snowfall & Winter StormWinter Weatherno Public Assistance recorded
1985-06-031985-05-31DR-737-PAMajor disasterSevere Storms, High Winds & TornadoesTornado (primary); also designated: Strong Windno Public Assistance recorded
1981-06-151981-06-15DR-641-PAMajor disasterSevere Storms & FloodingInland Floodingno Public Assistance recorded
1977-01-291977-01-29EM-3026-PAEmergencySnowstormsWinter Weatherno Public Assistance recorded
1972-06-231972-06-23DR-340-PAMajor disasterTropical Storm AgnesInland Flooding (primary); also designated: Hurricaneno 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
1959-01-231959-01-23DR-89-PAMajor disasterFloodsInland Flooding
1956-08-091956-08-09DR-61-PAMajor disasterStormHazard not mapped (severe storm title names no single hazard); not counted
1956-05-211956-05-21DR-58-PAMajor disasterSevere StormHazard not mapped (severe storm title names no single hazard); not counted
1956-03-151956-03-15DR-51-PAMajor disasterFloodInland Flooding
1955-08-201955-08-20DR-40-PAMajor disasterFloods & RainsInland 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.

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 Wave9201996 to 2026-06-30
Drought2001996 to 2026-06-30
Earthquake000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail1602601955 to 2026-06-30
Heat Wave0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Hurricane0021996 to 2026-06-30No Storm Events records of this type; 2 federal declared incidents (see declarations table)
Ice Storm10001996 to 2026-06-30
Inland Flooding105441996 to 2026-06-30
Landslide0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Lightning0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Strong Wind54714211955 to 2026-06-30Includes 22 High Wind and 2 Strong Wind records.
Tornado25121950 to 2026-06-30
Wildfire0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Winter Weather932421996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationFlagsWhy listed
2025-01-20Cold/Wind Chill$0 property; $0 crops (zone total, 2025 dollars)0, 0NWS zone PAZ007 (MERCER), zone-levelwithin last 5 yearsB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2019-05-28Hail2.75 indamage not reported0, 0SANDY LAKEB1-c worst recorded: Hail
2008-09-14High Wind50 kt (58 mph) estimated gust$1,000,000 property; $0 crops (zone total, 2008 dollars)0, 0NWS zone PAZ007 (MERCER), zone-levelB1-c most damaging: High Wind and Strong Wind
2005-01-05Ice Storm$20,000 property; crops not reported (zone total, 2005 dollars)0, 0NWS zone PAZ007 (MERCER), zone-levelB1-c worst recorded: Ice Storm
2004-12-20Heavy Snow$650,000 property; crops not reported (zone total, 2004 dollars)0, 100NWS zone PAZ007 (MERCER), zone-leveldeaths or injuries recorded
2002-11-10TornadoF2, 7 mi within this county, 500 yd wide$1,000,000 property; crops not reported (2002 dollars)1, 19SHARPSVILLEdeaths or injuries recorded
2002-08-16Flash Flood$250,000 property; crops not reported (2002 dollars)0, 0SHARONB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
2000-12-12High Wind61 kt (70 mph) estimated$50,000 property; crops not reported (zone total, 2000 dollars)0, 0NWS zone PAZ007 (MERCER), zone-levelB1-c worst recorded: High Wind and Strong Wind
1999-08-01Droughtdamage not reported0, 0NWS zone PAZ007 (MERCER), zone-levelB1-c worst recorded: Drought
1995-05-24Thunderstorm Wind130 kt (150 mph), measurement type not recorded$375,000 property; crops not recorded (1995 dollars)0, 0MercerB1-c worst recorded: Thunderstorm Wind
1985-05-31TornadoF5, 12 mi path length (whole path, pre-1996), 450 yd wide$250,000 property; crops not recorded (1985 dollars)8, 60location not recordeddeaths or injuries recorded
1985-05-31TornadoF4, 7 mi path length (whole path, pre-1996), 350 yd wide$25,000,000 property; crops not recorded (1985 dollars)0, 5location not recordedB1-c most damaging: Tornado

The full list is in the Excel file, sheet "B1-d Storm Events history" (951 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 Wave3.63event-days per yearabout 3.63 days per yearLikelyStorm Events event-days in 6 of 30 years, 1996 to 2025 (20%)692005-11-12 to 2024-11-12 (19 years)countywide
Drought0event-days per yearnone modeledPossibleStorm Events event-days in 1 of 30 years, 1996 to 2025 (3.33%)02000 to 2025 (25.25 years; D3 and D4 only)countywideNRI models no drought event-days here (2000 to 2025, 25.25 years; D3 and D4 only); Storm Events has a record in 1 of 30 years. The descriptor comes from Storm Events, which counts D2 drought that NRI leaves out.
Earthquake0.000598annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.0598%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail3.79events per yearabout 3.79 per yearHighly likelyFEMA annualized frequency (modeled)144.0 (modeled)1986 to 2023 (38 years)countywide
Heat Wave1.05event-days per yearabout 1.05 days per yearStorm Events event-days in 0 of 30 years, 1996 to 2025 (0%)222005-11-12 to 2024-11-12 (19 years)countywideNo Storm Events heat wave record, 1996 to 2025
Hurricane0.0237events per yearabout 1 in 42 yearsPossibleFEMA annualized frequency (modeled)81851 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 Storm0.447event-days per yearabout 0.447 days per yearLikelyStorm Events event-days in 6 of 30 years, 1996 to 2025 (20%)301946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding2.5event-days per yearabout 2.5 days per yearLikelyStorm Events event-days in 24 of 30 years, 1996 to 2025 (80%)701996 to 2023 (28 years)see B1-f
Landslide0.201events per year (modeled)about 1 in 5 yearsLikelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning39.6days per year with a strikeabout 39.6 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind2.28events per yearabout 2.28 per yearHighly likelyFEMA annualized frequency (modeled)871986 to 2023 (38 years)countywide
Tornado0.281events per yearabout 1 in 4 yearsLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Wildfire0.0000548annual probability at a locationchance a given location in the county burns in a year: 0.00548%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 Weather16.8event-days per yearabout 16.8 days per yearLikelyStorm Events event-days in 25 of 30 years, 1996 to 2025 (83.3%)3202005-11-12 to 2024-11-12 (19 years)countywide

FEMA annualized frequency (modeled) is the National Risk Index v1.20 (December 2025) estimate of how often a hazard affects this county in a year; it is not recorded events divided by years, and its unit differs by hazard (events, event-days, or days with a lightning strike per year). For earthquake, wildfire, coastal flooding and tsunami the value is the chance (or number of events) at a location in the county, not across the county, so no "1 in N years" is given and the descriptor comes from Storm Events where it has a record (none for earthquake). The Methods page gives each hazard's method, from FEMA's National Risk Index Technical Documentation v1.20.

Where NRI gives event-days, the descriptor comes from the share of years with a Storm Events record; NRI's source records more events, so the two differ.

Descriptor scale used in this packet (defined per unit)

Sources: 5, 6

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

Intensity bands: historical frequency (Storm Events)

Source: 6

HazardBandYearsEventscounty-coded recordsYears in periodEvents per yearevents / years
Hail1.00-1.99 in1996 to 202573302.43
Hail2.00 in+1996 to 20254300.133
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 20253893013
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 20253300.1
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 202557301.9
TornadoEF0-11996 to 202510300.333
TornadoEF2-31996 to 20251300.0333
TornadoEF4-51996 to 20250300
Tornadounrated (EFU)1996 to 20251300.0333

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 Wave35 of 3519.422.229.6Relatively Low 35
Drought0 of 35No Rating 35
Earthquake35 of 359.920.541.7Relatively Low 1, Very Low 34
Hail35 of 3547.968.282.7Relatively Moderate 14, Relatively Low 21
Heat Wave35 of 352.74.08.5Very Low 35
Hurricane35 of 3542.651.360.4Relatively Low 17, Very Low 18
Ice Storm35 of 356.718.064.8Relatively Low 5, Very Low 30
Inland Flooding35 of 355.565.795.4Relatively High 11, Relatively Moderate 12, Relatively Low 8, Very Low 4
Landslide35 of 3515.548.584.5Relatively Low 4, Very Low 31
Lightning35 of 3549.074.793.5Relatively High 15, Relatively Moderate 19, Relatively Low 1
Strong Wind35 of 3541.565.084.0Relatively High 2, Relatively Moderate 24, Relatively Low 9
Tornado35 of 3528.840.757.2Relatively Moderate 4, Relatively Low 29, Very Low 2
Wildfire35 of 3525.958.575.0Relatively Low 6, Very Low 29
Winter Weather35 of 3544.064.584.7Relatively High 4, Relatively Moderate 26, Relatively Low 5

Rated tracts only: No Rating (score 0.0), Not Applicable and Insufficient Data tracts are counted but not used for the minimum, median and maximum.

The score ranks a tract against all U.S. tracts (100 = highest). The rating is FEMA's category for the tract's risk value, computed differently, so the two can disagree.

Frequency data for cold wave, hail, heat wave, ice storm, lightning, strong wind and winter weather are county-wide or coarse (49 km grid or NWS zone), the same for every jurisdiction; the tract range mostly reflects where buildings and people are.

Each jurisdiction (starting figures from federal data)

Sources: 1, 3, 4, 6

JurisdictionTypePlan statusRepetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definitionPublic Assistance to this jurisdictionFEMA records matched by applicant name; federal share obligated, nominal dollarsEvent records naming this placeall years; since its planNotes
Clark boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$6,121.768 total; 1 since its plan
Farrell cityCityApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$3,863.6934 total; 6 since its plan
Fredonia boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$833.6219 total; 2 since its plan
Greenville boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$27,227.9761 total; 1 since its plan
Grove City boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$30,756.5758 total; 13 since its plan
Hermitage cityCityApproved, expires 2028-03-19FMA RL 0, SRL 0; any 1$128,282.4930 total; 7 since its planIncludes $3,862.41 for declarations not counted as hazard incidents (DR-4506-PA).
Jackson Center boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded16 total; 7 since its plan
Jamestown boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$35,238.6835 total; 5 since its plan
Mercer boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 1no Public Assistance recorded74 total; 10 since its plan
New Lebanon boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$4,368.7611 total; 0 since its plan
Sandy Lake boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded36 total; 4 since its plan
Sharon cityCityApproved, expires 2028-03-19FMA RL 0, SRL 2; any 2$148,651.9151 total; 4 since its planIncludes $94,655.64 for declarations not counted as hazard incidents (DR-4506-PA).
Sharpsville boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$23,341.7827 total; 11 since its plan
Sheakleyville boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded7 total; 1 since its plan
Stoneboro boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 1; any 1no Public Assistance recorded21 total; 3 since its plan
West Middlesex boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$57,131.8419 total; 4 since its plan
Wheatland boroughOrganized BoroughApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$2,362.646 total; 1 since its plan
Coolspring townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 1$4,127.620 total; 0 since its plan
Deer Creek townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$17,476.610 total; 0 since its plan
Delaware townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$31,699.020 total; 0 since its plan
East Lackawannock townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
Fairview townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$10,598.314 total; 2 since its plan
Findley townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$5,381.600 total; 0 since its plan
French Creek townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 1$50,932.510 total; 0 since its plan
Greene townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$30,643.670 total; 0 since its plan
Hempfield townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 1$15,566.660 total; 0 since its plan
Jackson townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
Jefferson townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$32,687.910 total; 0 since its plan
Lackawannock townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$3,895.160 total; 0 since its plan
Lake townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
Liberty townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$36,622.460 total; 0 since its plan
Mill Creek townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
New Vernon townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$24,930.145 total; 2 since its plan
Otter Creek townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$21,636.210 total; 0 since its plan
Perry townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$58,044.840 total; 0 since its plan
Pine townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$14,225.500 total; 0 since its plan
Pymatuning townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 2$7,708.160 total; 0 since its plan
Salem townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$15,956.345 total; 1 since its plan
Sandy Creek townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$60,837.600 total; 0 since its plan
Sandy Lake townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded36 total; 4 since its plan
Shenango townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$48,946.728 total; 4 since its plan
South Pymatuning townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$37,227.220 total; 0 since its plan
Springfield townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$21,248.820 total; 0 since its plan
Sugar Grove townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$5,175.390 total; 0 since its plan
West Salem townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 1$15,873.560 total; 0 since its plan
Wilmington townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$8,297.120 total; 0 since its plan
Wolf Creek townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0$6,242.540 total; 0 since its plan
Worth townshipTownshipApproved, expires 2028-03-19FMA RL 0, SRL 0; any 0no Public Assistance recorded0 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.

No county-level plan row in FEMA data, so there is no approval date to count from.

  • Critical facilities and lifelines per hazard
  • A problem statement per jurisdiction per hazard
  • Changes in development in hazard-prone areas since the last approval, or a statement of none (E1-a)
  • Future assets

County-level starter: exposure, expected annual loss and damage since the plan

Sources: 1, 2, 3, 5, 6, 7

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 plancounty-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$31,203,587,586$84,633,276110,623$1,219$18,244$235,637under 0.0001%
Droughtn/a$0n/an/a$0n/aagriculture exposure is 0 in NRI
Earthquake$52,387,568,599n/a110,652$210,210n/a$58,3360.000401%
Hail$31,203,587,586$84,633,276110,623$573,680$45,249$28,3220.00184%
Heat Wave$31,203,587,586$84,633,276110,623$6$2,044$108,353under 0.0001%
Hurricane$31,189,160,766$84,025,530110,567$271,438$25,714$9,3170.00087%
Ice Storm$31,130,235,737n/a110,127$23,751n/a$29,558under 0.0001%
Inland Flooding$31,177,952,273$1,136,6301,362$29,006,613$24,355$28,640n/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$395,953,065n/a1,461$241n/a$496under 0.0001%
Lightning$31,203,587,586n/a110,623$9,514n/a$916,982under 0.0001%
Strong Wind$31,203,587,586$84,633,276110,623$522,702$2,699$455,1040.00168%
Tornado$31,203,587,586$84,633,276110,623$980,065$2,310$356,3430.00314%
Wildfire$8,072,437,439$23,252,27729,458$16,481$11$2,1970.000204%
Winter Weather$31,203,587,586$84,633,276110,623$136,943$43$31,0860.000439%

Totals since the plan: not available. No county-level plan row in FEMA data, so there is no approval date to count from.

FEMA does not split Public Assistance by hazard. A declaration mapped to several hazards is listed under each of them with its full amount, so the per-hazard column does not add up to the total; the unit total counts each declaration once.

NRI computes earthquake exposure on its own basis, so it exceeds the county building value in B2-a.

Supports FEMA checklist item B2-a: vulnerability (county context)

County context

Source: 5

MeasureValue
Population110,623
Building value (total, not at risk)$31,203,587,586
Agriculture value (total, not at risk)$84,633,276
NRI risk rating (all hazards)Relatively Low
Expected annual loss, buildings and agriculture, all hazards$31,873,529
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)$2,260,373
Social vulnerability ratingRelatively Moderate
Community resilience ratingRelatively High
NRI versionDecember 2025

FEMA's all-hazard expected annual loss adds buildings, agriculture and population equivalence; this table gives the property part and the population-equivalence part as separate rows.

Social vulnerability: higher means people are more likely to be harmed and slower to recover. Community resilience: lower means the community is less able to recover. High social vulnerability and low resilience both raise the NRI risk rating.

Supports FEMA checklist item B2-c: repetitive loss properties

Repetitive loss in this county, both definitions

Sources: 1, 4

DefinitionPropertiesSevere repetitive lossProperties
Repetitive loss, FMA definition (44 CFR 77.2)0Severe repetitive loss, FMA definition (44 CFR 77.2)3
Repetitive loss, NFIP insurance definition11Severe repetitive loss, NFIP insurance definition3

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 total031131101
of which: Mercer borough0010100
of which: Sharon city0222200
of which: Stoneboro borough0111100
of which: Hermitage city0010101
of which: Coolspring township0010100
of which: French Creek township0010100
of which: Hempfield township0010100
of which: Pymatuning township0020200
of which: West Salem township0010100
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
Clark borough4224750000000
Farrell city4206730000000
Fredonia borough4224770000000
Greenville borough4206740000000
Grove City borough4206750000000
Hermitage city4218620010101
Jackson Center borough4224790000000
Jamestown borough4224810000000
Mercer borough4206760010100
New Lebanon borough4224840000000
Sandy Lake borough4206770000000
Sharon city4206780222200
Sharpsville borough4206820000000
Sheakleyville borough4227150000000
Stoneboro borough4206790111100
West Middlesex borough4206800000000
Wheatland borough4206810000000
Coolspring township4218630010100
Deer Creek township4224760000000
Delaware township4222830000000
East Lackawannock township4218640000000
Fairview township4218650000000
Findley township4218660000000
French Creek township4218670010100
Greene township4224780000000
Hempfield township4218680010100
Jackson township4224800000000
Jefferson township4218690000000
Lackawannock township4224820000000
Lake township4224830000000
Liberty township4218700000000
Mill Creek township4218710000000
New Vernon township4224850000000
Otter Creek township4224860000000
Perry township4224870000000
Pine township4222840000000
Pymatuning township4222850020200
Salem township4218720000000
Sandy Creek township4218730000000
Sandy Lake township4218740000000
Shenango township4218750000000
South Pymatuning township4218760000000
Springfield township4218770000000
Sugar Grove township4224890000000
West Salem township4224900010100
Wilmington township4218780000000
Wolf Creek township4224910000000
Worth township4224920000000

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 residential0171700
2 to 4 unit residential0000000
other residential0000000
non-residential0242401
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 11 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). Mercer County, PA: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 42085). Automated baseline. https://hazardplain.org/pa/42085/ 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: contact@hazardplain.org