Hazard Plain Automated baseline

Grayson County, TX

Risk-assessment baseline packet

County FIPS:
48181
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 2028-10-12. Plan: Grayson County (FEMA plan 105993), approved 2023-10-13.

Since the plan was approved on 2023-10-13: no new federal declaration.

NOAA Storm Events records since that date: 165 records (data through 2026-06-30).

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($19,019,131 a year), Tornado ($9,211,921) and Cold Wave ($4,202,099).

Repetitive-loss flood properties now: FMA RL 10, SRL 20 (44 CFR 77.2); any definition: 62.

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 2028-10-12
Plan:
Grayson County (FEMA plan 105993)
Approved:
2023-10-13
Days to expiry:
743

What changed since your last plan (approved 2023-10-13)

New federal declarations:
none
Storm Events records since approval:
165 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 10, SRL 20 (44 CFR 77.2); any definition: 62
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: 31 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 expiryNotes
Grayson CountyCountyApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743
Bells townTownApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Collinsville townTownApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2023-11-01
Denison cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Dorchester cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Gunter cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Howe townTownApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Knollwood cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Pottsboro townTownApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Sadler cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-03-25
Sherman cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Southmayd cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Tioga townTownApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Tom Bean cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Van Alstyne cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Whitesboro cityCityApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Whitewright townTownApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Bells Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Collinsville Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Denison Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Gunter Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Howe Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Pottsboro Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
S and S Consolidated Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Sherman Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-03-25
Tioga Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Tom Bean Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Trenton Independent School DistrictSchool/School DistrictApproved, expires 2027-10-26Fannin County (FEMA plan 107110)2022-10-272027-10-26391
Van Alstyne Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Whitesboro Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-01-25
Whitewright Independent School DistrictSchool/School DistrictApproved, expires 2028-10-12Grayson County (FEMA plan 105993)2023-10-132028-10-12743this jurisdiction approved 2024-02-08

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$17,253,739$27,507$1,737,885$19,019,131118
2TornadoRelatively HighRelatively High$1,664,279$1,584$7,546,058$9,211,92121
3Cold WaveRelatively ModerateRelatively High$164,339$69,798$3,967,962$4,202,0998
4Heat WaveRelatively ModerateRelatively Moderate$485$370$4,047,288$4,048,14354
5HailRelatively ModerateRelatively Moderate$2,235,921$227$94,973$2,331,122369
6Ice StormRelatively HighRelatively High$896,185n/a$200,735$1,096,9215
7WildfireRelatively LowRelatively Low$694,113$418$80,352$774,8836
8EarthquakeRelatively LowRelatively Low$528,829n/a$133,333$662,161Storm Events does not record earthquakes.
9Strong WindRelatively ModerateRelatively Moderate$181,107$641$462,449$644,197276Includes 5 High Wind and 7 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition).
10LightningRelatively LowRelatively Low$53,808n/a$236,761$290,56915
11DroughtRelatively LowRelatively Lown/a$124,557n/a$124,55776
12HurricaneVery LowVery Low$87,946$11,448$3,970$103,3641Includes 1 Tropical Depression record (outside NRI's Hurricane definition).
13Winter WeatherRelatively LowRelatively Moderate$79,786$503$1,997$82,28544Includes 2 Sleet records (outside NRI's Winter Weather definition).
14LandslideVery LowVery Low$2,778n/a$29$2,8060No recorded events in Storm Events since 1996 (data through 2026-06-30).

Total = buildings + agriculture + population equivalence; FEMA values each expected death (or 10 injuries) at $13.7 million (2024 dollars).

NRI risk rating combines expected annual loss with social vulnerability and community resilience; EAL rating rates expected annual loss alone. Both compare this county with all U.S. counties.

Local data needed: state and local landslide records (Storm Events records this hazard 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 9.03 (Relatively Low, 61.8); tract 3.02 (Relatively Low, 58.7); tract 18.01 (Relatively Low, 57.9)
Hurricanetract 18.01 (Relatively Low, 51.6); tract 18.02 (Very Low, 51.2); tract 19.02 (Very Low, 50.1)
Landslidetract 3.05 (Relatively Low, 92.5); tract 3.04 (Relatively Low, 90.7); tract 3.02 (Relatively Low, 90.4)
Tornadotract 18.01 (Very High, 96.4); tract 15 (Very High, 94.1); tract 3.02 (Relatively High, 93.2)
Wildfiretract 11.04 (Relatively Moderate, 94.9); tract 3.02 (Relatively Moderate, 94.8); tract 3.04 (Relatively Moderate, 94.8)

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 9.03 is Census Tract 9.03). 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 chill8 records, 1997 to 2026 (8 zone-level)1 day to 6 days (median 3 days); 8 with a recorded value6 consecutive days, 2021-02-14 to 2021-02-19, zone-levelCountywide (zone-level records).Wind chill: in event narratives only (local data needed).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage0Temperature: in event narratives only (local data needed).
DroughtU.S. Drought Monitor scale (D0 to D4)76 records, 1996 to 2024 (76 zone-level)6 days to 373 days (median 44 days); 25 with a recorded value373 days (about 12.3 months), 2005-05-01 to 2006-05-08, a run of 13 consecutive Storm Events drought records, zone-levelDrought, 2006-10-01, $500,000 property; $500,000 crops, reported for the zone (2006 dollars)Countywide (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)486 records, 1955 to 20260.75 in to 4.5 in (median 1 in); 484 with a recorded value4.5 in hail, 1996-04-21; same size also recorded on 1989-05-16, 1996-04-21Hail, 1995-04-29, $20,000,000 property; crops not recorded (1995 dollars)Event records naming jurisdictions in the plan: Sherman city (37 records), Denison city (33 records), Whitesboro city (27 records), Pottsboro town (24 records), Tom Bean city (22 records), Van Alstyne city (21 records), Sadler city (19 records), Tioga town (15 records), Collinsville town (13 records), Gunter city (13 records); and 5 more jurisdictions (see the Excel file).
Excessive Heat, Heatheat index (in event narratives)54 records, 1998 to 2026 (54 zone-level)1 day to 85 days (median 3 days); 37 with a recorded valueJuly 2000 to September 2000 (3 monthly summary records), zone-levelCountywide (zone-level records).Heat index: in event narratives only (local data needed).
Hurricane, Tropical Storm, Tropical DepressionSaffir-Simpson1 record, 2008 (1 zone-level)Strongest recorded: Tropical Depression record, 2008-09-02, $5,000 property; $0 crops (2008 dollars); NWS zone TXZ093Countywide (zone-level records).Storm 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, 1998 to 2011 (5 zone-level)Ice Storm, 2011-02-01, $150,000 property; $0 crops (2011 dollars); NWS zone TXZ093Countywide (zone-level records).Ice thickness: in event narratives only (local data needed).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)118 records, 1996 to 2026Flash Flood, 2007-06-18, $20,000,000 property; $0 crops (2007 dollars), 2 direct deathsEvent records naming jurisdictions in the plan: Denison city (17 records), Sherman city (15 records), Tioga town (14 records), Gunter city (7 records), Collinsville town (6 records), Van Alstyne city (6 records), Bells town (4 records), Howe town (4 records), Whitewright town (4 records), Whitesboro city (3 records); and 4 more jurisdictions (see the Excel file).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)15 records, 1996 to 2025Lightning, 2025-06-08, $0 property; $0 crops (2025 dollars), 1 direct death, 1 direct injuryLightning, 2006-08-06, $130,000 property; crops not reported (2006 dollars)Event records naming jurisdictions in the plan: Denison city (4 records), Collinsville town (2 records), Sadler city (2 records), Sherman city (2 records), Gunter city (1 record), Howe town (1 record), Southmayd city (1 record), Van Alstyne city (1 record), Whitesboro city (1 record).Storm 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, 2005 to 2025 (12 zone-level)32 kt (37 mph) to 55 kt (63 mph) (median 43 kt (49 mph)); 12 with a recorded value55 kt (63 mph) measured gust, High Wind, 2025-03-04; NWS zone TXZ093High Wind, 2007-02-24, $300,000 property; $0 crops, reported for the zone (2007 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)388 records, 1957 to 202643 kt (49 mph) to 90 kt (104 mph) (median 55 kt (63 mph)); 278 with a recorded value90 kt (104 mph), measurement type not recorded, Thunderstorm Wind, 1982-05-31Thunderstorm Wind, 2025-07-31, $200,000 property; $0 crops (2025 dollars)Event records naming jurisdictions in the plan: Denison city (33 records), Sherman city (33 records), Whitesboro city (23 records), Pottsboro town (19 records), Gunter city (16 records), Van Alstyne city (16 records), Collinsville town (11 records), Howe town (11 records), Tioga town (10 records), Sadler city (7 records); and 5 more jurisdictions (see the Excel file).
TornadoEnhanced Fujita (Fujita before Feb 2007)71 records, 1952 to 2025F/EF0 to F/EF3 (median F/EF1); 70 with a recorded valueF3 tornado, 1955-04-06, 11.9 mi path length (whole path, pre-1996), 67 yd wide, $2,500,000 property; crops not recorded (1955 dollars), 1 direct death, 27 direct injuriesEvent records naming jurisdictions in the plan: Sadler city (3 records), Sherman city (3 records), Denison city (2 records), Pottsboro town (2 records), Whitesboro city (2 records), Bells town (1 record), Collinsville town (1 record), Gunter city (1 record), Howe town (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)6 records, 2008 to 2018 (6 zone-level)Wildfire, 2008-01-29, $400,000 property; $0 crops (2008 dollars); NWS zone TXZ093Countywide (zone-level records).Acres burned: in event narratives only (local data needed).
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall: local data)44 records, 1996 to 2026 (44 zone-level)Winter Storm, 2013-12-05, $7,000,000 property; $0 crops (2013 dollars); NWS zone TXZ093Countywide (zone-level records).Snow depth: in event narratives only (local data needed).

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".

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.

A monthly summary record covers most or all of a month; it does not count days at wave conditions.

Supports FEMA checklist item B1-d: previous occurrences

Federal declarations for this county: 21 declarations covering 13 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
2021-02-192021-02-11DR-4586-TXMajor disasterSevere Winter StormsIce Storm$62,580.88
2021-02-142021-02-11EM-3554-TXEmergencySevere Winter StormIce Stormno Public Assistance recordedsame incident as DR-4586
2020-03-252020-01-20DR-4485-TXMajor disasterCOVID-19 PandemicNon-natural, not counted$75,483.42
2020-03-132020-01-20EM-3458-TXEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedsame incident as DR-4485
2015-05-292015-05-04DR-4223-TXMajor disasterSevere Storms, Tornadoes, Straight-Line Winds and FloodingInland Flooding; Strong Wind; Tornado$1,775,232
2011-09-092011-08-30DR-4029-TXMajor disasterWildfiresWildfire$57,777.24
2008-09-102008-09-07EM-3294-TXEmergencyHurricane IkeHurricaneno Public Assistance recorded
2008-03-142008-03-14EM-3284-TXEmergencyWildfiresWildfireno Public Assistance recorded
2007-06-292007-06-16DR-1709-TXMajor disasterSevere Storms, Tornadoes, and FloodingInland Flooding; Tornado$1,350,010.64
2006-01-112005-11-27DR-1624-TXMajor disasterExtreme Wildfire ThreatWildfire$2,004.51
2005-09-242005-09-23DR-1606-TXMajor disasterHurricane RitaHurricane: evacuation support (county designated for sheltering evacuees, no Individual Assistance), not a local hazard event; not countedno Public Assistance recorded
2005-09-212005-09-20EM-3261-TXEmergencyHurricane RitaHurricane: evacuation support (county designated for sheltering evacuees, no Individual Assistance), not a local hazard event; not countedno Public Assistance recordedsame incident as DR-1606
2005-09-022005-08-29EM-3216-TXEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not counted$9,843.95
2003-02-012003-02-01EM-3171-TXEmergencyLoss of the Space Shuttle ColumbiaNon-natural, not countedno Public Assistance recorded
2001-01-082000-12-12DR-1356-TXMajor disasterSevere Winter Ice StormIce Storm$740,010.39
1999-09-011999-08-01EM-3142-TXEmergencyExtreme Fire HazardsWildfireno Public Assistance recorded
1998-08-261998-08-22DR-1239-TXMajor disasterTropical Storm CharleyHurricane; Inland Flooding: designated for Hazard Mitigation only (no Public or Individual Assistance for this county); not countedPA not declared for this county
1993-09-101993-08-30EM-3113-TXEmergencyExtreme Fire HazardDrought (primary); also designated: Wildfireno Public Assistance recorded
1990-05-021990-04-15DR-863-TXMajor disasterSevere Storms, Tornadoes & FloodingInland Flooding; TornadoPA not declared for this county
1989-05-191989-05-04DR-828-TXMajor disasterSevere Storms, Tornadoes & FloodingInland Flooding; Tornadono Public Assistance recorded
1981-10-231981-10-23DR-648-TXMajor disasterSevere Storms & FloodingInland Floodingno Public Assistance recorded

School districts and special districts in this county: $122,605.69 (included in the county total above). Public Assistance matched by applicant name to the school districts and special districts FEMA lists as plan participants in this county. They have no row of their own in the jurisdiction table, so their total is listed here. These dollars are already included in the county PA column of the declarations table (the FEMA record places each applicant in this county), so this line is not added to it.

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
1998-06-231998-06-04EM-3127-TXEmergencyFireWildfire
1963-09-241963-09-24DR-159-TXMajor disasterHurricane CindyHurricane (primary); also designated: Inland Flooding
1961-09-161961-09-16DR-118-TXMajor disasterHurricane CarlaHurricane (primary); also designated: Inland Flooding
1960-07-151960-07-15DR-103-TXMajor disasterHeavy Rains, Hail, Floods & TornadoesHail; Inland Flooding; Tornado
1959-07-081959-07-08DR-93-TXMajor disasterFloodsInland Flooding
1958-06-061958-06-06DR-85-TXMajor disasterTornadoes, Rain, Hail & FloodsTornado (primary); also designated: Hail, Inland Flooding
1957-04-291957-04-29DR-72-TXMajor disasterHurricane, Rain, Wind, Hail & FloodsHurricane (primary); also designated: Hail, Inland Flooding
1954-07-011954-07-01DR-18-TXMajor disasterFloodInland Flooding
1953-06-191953-06-19DR-9-TXMajor disasterFloodInland Flooding
1953-05-151953-05-15DR-2-TXMajor disasterTornado & Heavy RainfallTornado

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.

91 Fire Management declarations (1988-03-12 to 2009-04-10) FEMA filed as Statewide with no county; each names one local fire. Listed on the state page.

Public Assistance not placed in any Texas county: 1 row, $902,084.65; listed on the Texas 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 Wave8505001996 to 2026-06-30
Drought763315101996 to 2026-06-30
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail4868828121001955 to 2026-06-30
Heat Wave54151234001996 to 2026-06-30
Hurricane1000101996 to 2026-06-30Includes 1 Tropical Depression record.
Ice Storm5000201996 to 2026-06-30
Inland Flooding11816928501996 to 2026-06-30
Landslide0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Lightning15202001996 to 2026-06-30
Strong Wind400321450101955 to 2026-06-30Includes 5 High Wind and 7 Strong Wind records.
Tornado71102401950 to 2026-06-30
Wildfire6000501996 to 2026-06-30
Winter Weather44316001996 to 2026-06-30Includes 2 Sleet records.

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationFlagsWhy listed
2025-06-08Lightning$0 property; $0 crops (2025 dollars)1, 1GUNTERnew since last plan; within last 5 yearsB1-c worst recorded: Lightning
2025-03-04High Wind55 kt (63 mph) measured gust$0 property; $0 crops, reported for the zone (2025 dollars)0, 0NWS zone TXZ093 (GRAYSON), zone-levelnew since last plan; within last 5 yearsB1-c worst recorded: High Wind and Strong Wind
2024-12-24Flood$50,000 property; $0 crops (2024 dollars)2, 0SHERMAN MUNI ARPTnew since last plan; within last 5 yearsdeaths or injuries recorded
2021-02-14Extreme Cold/Wind Chill$3,800,000 property; crops not reported, reported for the zone (2021 dollars)0, 0NWS zone TXZ093 (GRAYSON), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2011-02-01Ice Storm$150,000 property; $0 crops, reported for the zone (2011 dollars)0, 0NWS zone TXZ093 (GRAYSON), zone-levelB1-c worst recorded: Ice Storm
2008-01-29Wildfire$400,000 property; $0 crops, reported for the zone (2008 dollars)0, 0NWS zone TXZ093 (GRAYSON), zone-levelB1-c worst recorded: Wildfire
2007-06-18Flash Flood$20,000,000 property; $0 crops (2007 dollars)2, 0COLLINSVILLE to SHERMANdeaths or injuries recorded
2005-05-01Droughtdamage not reported0, 0NWS zone TXZ093 (GRAYSON), zone-levelB1-c worst recorded: Drought
2000-07-01Heatdamage not reported0, 0NWS zone TXZ093 (GRAYSON), zone-levelB1-c worst recorded: Excessive Heat, Heat
1996-04-21Hail4.5 indamage not reported0, 0DIXIEB1-c worst recorded: Hail
1982-05-31Thunderstorm Wind90 kt (104 mph), measurement type not recordeddamage not recorded (pre-1996 record)0, 0location not recordedB1-c worst recorded: Thunderstorm Wind
1955-04-06TornadoF3, 11.9 mi path length (whole path, pre-1996), 67 yd wide$2,500,000 property; crops not recorded (1955 dollars)1, 27location not recordeddeaths or injuries recorded

The full list is in the Excel file, sheet "B1-d Storm Events history" (1,284 rows).

Location is the place NOAA recorded, as written in its data; it need not be a jurisdiction in this plan.

Local data needed: state-declared emergencies, from your state emergency management agency (federal data do not include them).

Tribal and special-area declarations in this state are listed on the state page.

Supports FEMA checklist item B1-e: probability of future events

Probability: FEMA annualized frequency and descriptor per hazard

Sources: 5, 6

HazardFEMA annualized frequency (modeled)unit per rowUnitIn plain termsDescriptorDescriptor basisNRI events or days in its record period (hail, wind and tornado are area-weighted, so can be fractional)NRI periodLocationNote
Cold Wave1.05event-days per yearabout 1.05 days per yearLikely (from Storm Events: 5 of 30 years)event-days in 5 of 30 years, 1996 to 2025 (16.7%)202005-11-12 to 2024-11-12 (19 years)countywide
Drought28.1event-days per yearabout 28.1 days per yearLikely (from Storm Events: 17 of 30 years)event-days in 17 of 30 years, 1996 to 2025 (56.7%)1,1202000 to 2025 (25.25 years; D3 and D4 only)countywide
Earthquake0.00116annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.116%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail8.54events per yearabout 8.54 per yearHighly likelyFEMA annualized frequency (modeled)324.1 (modeled)1986 to 2023 (38 years)countywide
Heat Wave15.9event-days per yearabout 15.9 days per yearLikely (from Storm Events: 11 of 30 years)event-days in 11 of 30 years, 1996 to 2025 (36.7%)2602005-11-12 to 2024-11-12 (19 years)countywide
Hurricane0.0105events per yearabout 1 in 96 yearsPossibleFEMA annualized frequency (modeled)41851 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 Storm1.25event-days per yearabout 1.25 days per yearLikely (from Storm Events: 5 of 30 years)event-days in 5 of 30 years, 1996 to 2025 (16.7%)851946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding2.18event-days per yearabout 2.18 days per yearLikely (from Storm Events: 25 of 30 years)event-days in 25 of 30 years, 1996 to 2025 (83.3%)611996 to 2023 (28 years)see B1-f
Landslide0.185events per year (modeled)about 1 in 5 yearsLikelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning54.9days per year with a strikeabout 54.9 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind3.99events per yearabout 3.99 per yearHighly likelyFEMA annualized frequency (modeled)1511986 to 2023 (38 years)countywide
Tornado0.88events per yearabout 0.88 per yearLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Wildfire0.0015annual probability at a locationchance a given location in the county burns in a year: 0.15%Likely (from Storm Events: 4 of 30 years)Storm Events records in 4 of 30 years, 1996 to 2025 (13.3%)not shownmodeledsee B1-fDescriptor from Storm Events, not NRI.
Winter Weather4.95event-days per yearabout 4.95 days per yearLikely (from Storm Events: 21 of 30 years)event-days in 21 of 30 years, 1996 to 2025 (70%)942005-11-12 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 2025203306.77
Hail2.00 in+1996 to 202529300.967
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 2025201306.7
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 202521300.7
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 202540301.33
TornadoEF0-11996 to 202518300.6
TornadoEF2-31996 to 20253300.1
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 Wave30 of 3047.678.787.0Relatively High 17, Relatively Moderate 13
Drought20 of 3072.281.492.1Relatively Moderate 1, Relatively Low 12, Very Low 7, No Rating 10
Earthquake30 of 3023.241.661.8Relatively Low 15, Very Low 15
Hail30 of 3065.687.396.0Relatively High 12, Relatively Moderate 17, Relatively Low 1
Heat Wave30 of 3054.788.093.1Relatively High 18, Relatively Moderate 11, Relatively Low 1
Hurricane30 of 3034.643.451.6Relatively Low 1, Very Low 29
Ice Storm30 of 3073.091.196.8Relatively High 19, Relatively Moderate 11
Inland Flooding30 of 305.156.680.9Relatively High 2, Relatively Moderate 19, Relatively Low 6, Very Low 3
Landslide30 of 3011.168.592.5Relatively Low 5, Very Low 25
Lightning30 of 3021.248.564.2Relatively Moderate 14, Relatively Low 16
Strong Wind30 of 3027.457.076.6Relatively Moderate 21, Relatively Low 9
Tornado30 of 3061.088.496.4Very High 2, Relatively High 24, Relatively Moderate 4
Wildfire30 of 3020.085.994.9Relatively Moderate 14, Relatively Low 11, Very Low 5
Winter Weather30 of 3027.550.975.1Relatively Moderate 18, Relatively Low 12

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 planNotes
Grayson CountyCountyApproved, expires 2028-10-12FMA RL 6, SRL 6; any 14$2,082,283.710 total; 0 since its planIncludes $75,483.42 for declarations not counted as hazard incidents (DR-4485-TX).
Bells townTownApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$29,131.1119 total; 3 since its plan
Collinsville townTownApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$16,117.7333 total; 10 since its plan
Denison cityCityApproved, expires 2028-10-12FMA RL 1, SRL 1; any 5$469,735.2789 total; 11 since its plan
Dorchester cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$6,670.954 total; 0 since its plan
Gunter cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 1$20,007.6438 total; 8 since its plan
Howe townTownApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$60,233.3430 total; 5 since its plan
Knollwood cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
Pottsboro townTownApproved, expires 2028-10-12FMA RL 0, SRL 0; any 1$6,903.1747 total; 4 since its plan
Sadler cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0no Public Assistance recorded33 total; 2 since its plan
Sherman cityCityApproved, expires 2028-10-12FMA RL 3, SRL 13; any 41$831,287.5990 total; 1 since its planIncludes $9,843.95 for declarations not counted as hazard incidents (EM-3216-TX).
Southmayd cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$61,782.4517 total; 5 since its plan
Tioga townTownApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$13,732.2939 total; 2 since its plan
Tom Bean cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0no Public Assistance recorded26 total; 7 since its plan
Van Alstyne cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$206,275.7744 total; 9 since its plan
Whitesboro cityCityApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0no Public Assistance recorded56 total; 3 since its plan
Whitewright townTownApproved, expires 2028-10-12FMA RL 0, SRL 0; any 0$101,125.539 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).

School districts and special districts get a plan clock row only.

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
  • Texas A&M Forest Service TxWRAP for wildfire risk; Texas State Hazard Mitigation Plan hazard list for B1-a exclusions.

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 2023-10-13county-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$28,726,580,041$85,194,961135,451$164,339$69,798$3,967,9620.000572%$0
Droughtn/a$39,616,446n/an/a$124,557n/a0.314% (agriculture)$0NRI has no building exposure for this hazard; agriculture shown
Earthquake$50,967,231,598n/a135,543$528,829n/a$133,3330.00104%
Hail$28,726,598,869$85,194,961135,451$2,235,921$227$94,9730.00778%$559,000
Heat Wave$28,726,580,041$85,194,961135,451$485$370$4,047,288under 0.0001%$0
Hurricane$28,663,862,912$83,880,317134,989$87,946$11,448$3,9700.000307%
Ice Storm$28,724,121,868n/a135,413$896,185n/a$200,7350.00312%
Inland Flooding$28,715,875,608$4,025,3592,640$17,253,739$27,507$1,737,885n/a (see note)$72,000NRI 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$275,223,166n/a1,010$2,778n/a$290.00101%
Lightning$28,726,598,869n/a135,451$53,808n/a$236,7610.000187%$100,000
Strong Wind$28,726,598,869$85,194,961135,451$181,107$641$462,4490.00063%$825,000$0
Tornado$28,726,598,869$85,194,961135,451$1,664,279$1,584$7,546,0580.00579%$50,000
Wildfire$5,572,299,526$40,001,63441,575$694,113$418$80,3520.0125%
Winter Weather$28,726,580,041$85,194,961135,451$79,786$503$1,9970.000278%$0

Totals since 2023-10-13 (Storm Events through 2026-06-30): 137 county-coded records, 137 with a damage value recorded (including $0), $1,606,000; 28 zone-level records, 28 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
Population135,451
Building value (total, not at risk)$28,726,598,869
Agriculture value (total, not at risk)$85,194,961
NRI risk rating (all hazards)Relatively Low
Expected annual loss, buildings and agriculture, all hazards$24,080,367
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)$18,513,793
Social vulnerability ratingRelatively Low
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)10Severe repetitive loss, FMA definition (44 CFR 77.2)20
Repetitive loss, NFIP insurance definition58Severe repetitive loss, NFIP insurance definition18

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 total1020581862110
of which: Denison city1151502
of which: Grayson County (unincorporated area)661351414
of which: Gunter city0010100
of which: Pottsboro city0010100
of which: Sherman city31338124104
Statewide, no county in FEMA's file381271319

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
Grayson County480829661351414
Bells town4808300000000
Collinsville town4808310000000
Denison city4802591151502
Dorchester city4813090000000
Gunter city4808320010100
Howe town4808330000000
Knollwood city4802450000000
Pottsboro town4816220010100
Sadler city4811600000000
Sherman city48550931338124104
Southmayd city4811630000000
Tioga town4816240000000
Tom Bean city4816210000000
Van Alstyne city4816200000000
Whitesboro city4816230000000
Whitewright town4808390000000

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 residential763363506
2 to 4 unit residential0575700
other residential0120300
non-residential381671714
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 2 properties are FMA repetitive loss but not NFIP repetitive loss, and 50 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). Grayson County, TX: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 48181). Automated baseline. https://hazardplain.org/tx/48181/ 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

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