Automated baseline from FEMA and NOAA data, release 2026-10.

Grimes County, TX

Risk-assessment baseline packet. County FIPS 48185. Release 2026-10, data as of 2026-09-30.

Summary

Plan status as of 2026-09-30: Approved, expires 2029-08-07. Plan: Grimes County (FEMA plan 107724), approved 2024-08-08.

Since the plan was approved on 2024-08-08: 1 new hazard declaration (1 incident) and 4 NOAA Storm Events records; details under "What changed since your last plan".

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($3,109,087 a year), Cold Wave ($3,027,330) and Hurricane ($2,776,125).

The packet's tables are organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B (B1-a to B2-c); the summaries below follow the same order.

Download the packet

Full packet as a web page. File manifest (checksums, source versions).

Plan clock

Approved, expires 2029-08-07

Plan:
Grimes County (FEMA plan 107724)
Approved:
2024-08-08
Days to expiry:
1,042

What changed since your last plan (approved 2024-08-08)

New federal declarations:
1 new hazard declaration (1 incident): DR-4935-TX (Severe Storms, Straight-Line Winds, Tornadoes, and Flooding)
Storm Events records since approval:
4 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 3, SRL 2 (44 CFR 77.2); any definition: 10
Repeat-flood change:
this release sets the baseline count.

Plan status for every jurisdiction listed in this county

8 jurisdictions. Each row is that jurisdiction's own plan clock. Notes include other approved plans FEMA lists for the same jurisdiction.

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiryNotes
Grimes CountyCountyApproved, expires 2029-08-07Grimes County (FEMA plan 107724)2024-08-082029-08-071,042This jurisdiction approved 2025-01-10.
Anderson cityCityApproved, expires 2029-08-07Grimes County (FEMA plan 107724)2024-08-082029-08-071,042
Bedias cityCityApproved, expires 2029-08-07Grimes County (FEMA plan 107724)2024-08-082029-08-071,042
Iola cityCityApproved, expires 2029-08-07Grimes County (FEMA plan 107724)2024-08-082029-08-071,042
Navasota cityCityApproved, expires 2029-08-07Grimes County (FEMA plan 107724)2024-08-082029-08-071,042
Plantersville cityCityApproved, expires 2029-08-07Grimes County (FEMA plan 107724)2024-08-082029-08-071,042
Todd Mission cityCityPlan 107724 approved 2024-08-08, pending adoption here; not yet eligibleGrimes County (FEMA plan 107724), pending adoption here2024-08-08 by FEMA; not yet adopted here2029-08-07 once adoptedNot yet eligible: adopt the plan FEMA lists as approvable pending adoption.
San Jacinto River AuthorityFlood Control DistrictApproved, expires 2030-04-08Waller County (FEMA plan 110285)2025-04-092030-04-081,286

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

What the packet contains

Sections in FEMA checklist order; each heading names the review item its tables support. Full tables are in the downloads above.

Supports FEMA checklist item B1-a Hazard identification

14 of the 18 National Risk Index hazards apply here.

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.

Highest expected annual loss (NRI, modeled): Inland Flooding, Cold Wave and Hurricane.

Not covered by NRI (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 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

  • Cold Wave, Drought, Hail, Heat Wave, Ice Storm, Lightning, Strong Wind and Winter Weather: affects the whole county; national data give no location within it.
  • Earthquake, Hurricane, Landslide, Tornado and Wildfire vary within the county; the packet lists the highest-rated census tracts for each.
  • 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.

Supports FEMA checklist item B1-c Hazard extent

Storm Events records for 12 of the 20 NOAA event-type groups mapped to the 18 hazards, with the scale, observed range and worst recorded event for each; the others say which local data are needed.

Worst recorded tornado, hail and thunderstorm wind (the three event types on record since the 1950s; the packet has every group):

  • Hail: 2.5 in hail, 1981-02-10
  • Thunderstorm Wind: 70 kt (81 mph) estimated gust, Thunderstorm Wind, 2015-04-27; same speed and measurement basis also recorded on 2009-09-03
  • Tornado: F2 tornado, 1981-02-10, 2.5 mi path length (whole path, pre-1996), 77 yd wide, $250,000 property; crops not recorded (1981 dollars), 2 direct injuries

Supports FEMA checklist item B1-d Previous occurrences

Federal declarations for this area: 28 declarations covering 20 separate hazard incidents counted in this packet; each with type, dates and county Public Assistance dollars.

New since the last plan (approved 2024-08-08): DR-4935-TX.

10 statewide declarations listed separately.

Hazards with no Storm Events record and no federal declaration are stated as such (6 of 18).

Storm Events history: 250 records (notable ones in the PDF, all of them in the Excel file).

Supports FEMA checklist item B1-e Probability of future events

FEMA annualized frequency (modeled) for each hazard, with a descriptor from a scale defined in the packet.

  • Highly likely: Hail, Lightning and Strong Wind
  • Likely: Drought, Heat Wave, Ice Storm, Inland Flooding, Landslide, Tornado and Winter Weather
  • Possible: Cold Wave, Hurricane and Wildfire
  • Unlikely: Earthquake

Historical frequency by intensity band (tornado, hail, wind): 9 bands from Storm Events.

Supports FEMA checklist item B1-f Hazards that vary across jurisdictions

Range of census tract risk scores within the area for 14 of the 18 hazards (8 tracts; rated tracts only).

7 jurisdictions: plan clock, repeat-flood count, Public Assistance dollars and event records naming the place (starting figures from federal data).

County Public Assistance in B1-d also includes applicants filed under the county that are not matched to a jurisdiction row here (for example county departments filed under their own names, such as a highway department or emergency management agency, and 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

The packet's table gives county-level starting figures; the plan describes impacts for each jurisdiction and its own assets.

Storm Events damage since 2024-08-08: $0 in county-coded records (3 records); $0 reported for the zone (1 zone record). Data through 2026-06-30; nominal dollars.

Local data needed

To gather:

  • 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.

Supports FEMA checklist item B2-a Vulnerability (county context)

Population 29,203; building value $4,953,177,767 and agriculture value $61,220,223 (total, not at risk).

National Risk Index rating Relatively Low; social vulnerability Relatively High; community resilience Relatively Low.

Supports FEMA checklist item B2-c Repetitive loss properties

Repetitive-loss properties, FMA definition (44 CFR 77.2): 3 repetitive loss, 2 severe repetitive loss. NFIP insurance definition: 10 and 2.

Mitigated 0; insured 2; NFIP data as of 2026-08-02. Counts by occupancy group and for each jurisdiction are in the packet.

Releases

Each release is dated; this is release 2026-10. It was first published 2026-09-30; its files do not change except for dated corrections listed on the changelog (corrected 2026-10-01). Later releases will be listed here with what changed between them. All releases.

Cite this

Hazard Plain (2026). Grimes County, TX: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 48185). Automated baseline. https://hazardplain.org/tx/48185/ Built from FEMA OpenFEMA, the FEMA National Risk Index and NOAA NCEI Storm Events; source versions in the packet's Sources list.

Source citations for the plan's bibliography (8)

How this packet is built: methods and sources