The Impact plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
Showers likely
Showers likely
Mostly cloudy
Partly cloudy
Partly cloudy
Mostly cloudy
Mostly sunny
90° on Nov. 17, 2025, the hottest reading for this week of the year since 1885. Next is 87° in 1911.
Impact’s center stands about 1,670 ft above sea level. Within three miles the land runs from 1,640 ft to 1,760 ft, a difference of 120 ft: gently rolling country. The highest named summit within 15 miles is Flattop, about 2,030 ft, 13 miles east.
Under the town center the state geologic map shows Alluvium (fine-detrital, coarse-detrital), from the Holocene, less than 12,000 years old.
The section below crosses 5 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Claystone. Age: Permian, 252 to 299 million years old. About 9 mi of the line.
Fine-detrital, coarse-detrital. Age: Holocene, less than 12,000 years old. About 6 mi of the line.
Shale. Age: Permian, 252 to 299 million years old. About 4 mi of the line.
Coarse-detrital, fine-detrital. Age: Quaternary, less than 2.6 million years old. About 4 mi of the line.
Conglomerate. Age: Pleistocene, less than 2.6 million years old. About 1 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in Impact reaches the Gulf of America by way of Elm Creek, the Clear Fork and the Brazos: about 950 river miles.
Lakes on the way: Possum Kingdom Lake, Lake Granbury and Fort Phantom Hill Lake.
550 miles of the trip are on the Brazos.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Impact; river miles along the main stem, rounded.
Impact has a humid subtropical climate. Summer afternoons average 96° in July; winter nights fall to about 34° in January. About 25 inches of rain fall in a normal year, with about 4 inches of snow.
On November 14 Impact normally reaches 68° and falls to 44°. The record high is 89°, in 2025; the record low 14°, in 1976. The most rain on this date, 1.54 in, fell in 1954.
Normals 1991–2020 and records since 1885 from the Abilene Area threaded record (Abilene Regional Airport, 7 miles south-southeast, 120 ft higher). NOAA, through RCC-ACIS.
