Armstrong County, Texas
Shrink-swell clay limits houses without basements on 45% of Armstrong County's mapped land, a higher share than 89% of US counties. A shallow water table limits basements on 6%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list no flood losses here since 2016. 75% of homes were built before 1980, against 50% nationally; the median home dates from 1965.
Data as of October 13, 2026 · sources
expansive clay: shrink-swell limits slab homes
high water table: limits basements
in drought, October 13, 2026
of homes built before 1980
Soil under Armstrong County
| Expansive clay (limits slab homes) | 44.9% |
| High water table (limits basements) | 5.6% |
| Septic fields very limited | 72.3% |
| Clay swell (LEP, by area) | 4.5% |
| High-swell land (LEP 6%+) | 43.8% |
| Mapped soil | 584,615 acres |
How we count · survey areas TX011 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 4.5% by land area here, and 44% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 45% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 45% of Armstrong County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 12.16 in, 8.41 in below the 1991-2020 average year of 20.57 in.
USDA rates 72% of the land very limited for septic absorption fields.
Drought
100% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 47 of the last 52 weeks; the most was 100% of its area, in 33 weeks, most recently on the October 13, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 100% |
| D2 severe or worse | 96.4% |
| D3 extreme or worse | 41.5% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Armstrong County since 2016.
Rain
| Average year, 1991-2020 | 20.57 in |
| 12 months to August 2026 | 12.16 in (-8.41) |
| 2025 | 22.61 in (+2.04) |
| Wettest year since 1895 | 1923: 38.60 in |
| Driest year since 1895 | 2011: 8.10 in |
| Days with 1 inch or more, normal at CLARENDON (26 mi away) | 5.7 |
Homes
| Housing units | 886 |
| Median year built | 1965 |
| Built before 1980 | 75% |
| Built 2000 or later | 8% |
| Owner-occupied | 80% |
| Median value, owner-occupied | $171,500 |
| Single-family detached | 91% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Armstrong County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Claude | 99% | 1% | 551 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Carson County, TX | 31 mi | 55% | 7% |
| Randall County, TX | 31 mi | 66% | 7% |
| Donley County, TX | 31 mi | 4% | 1% |
| Briscoe County, TX | 32 mi | 40% | 8% |
| Swisher County, TX | 37 mi | 87% | 10% |
| Potter County, TX | 43 mi | 19% | 2% |
| Gray County, TX | 43 mi | 31% | 4% |
| Hall County, TX | 57 mi | 1% | under 1% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status