The Twin Hills Colony 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.
Mostly sunny
Partly cloudy
Partly cloudy
Showers likely; cooler
Partly cloudy
Mostly cloudy
Mostly cloudy
74° on Nov. 12, 1999, the hottest reading for this week of the year since 1982. Next is 73° in 1990.
Twin Hills Colony’s center stands about 3,300 ft above sea level. Within three miles the land runs from 3,200 ft to 3,600 ft, a difference of 400 ft: rolling country. The highest named summit within 15 miles is West Knee, about 3,850 ft, 13 miles west.
Under the town center the state geologic map shows Telegraph Creek Formation (sandstone, siltstone, shale), from the Late Cretaceous, 84 to 87 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 26×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, siltstone, shale. Age: Late Cretaceous, 84 to 87 million years old. About 11 mi of the line.
Sandstone, sandstone-mudstone. Age: Late Cretaceous, 72 to 87 million years old. About 6 mi of the line.
Shale, limestone, dolostone. Age: Late Cretaceous, 84 to 90 million years old. About 6 mi of the line.
Gravel, sand, silt. Age: Pleistocene to Holocene, less than 1.8 million years old. About 0.5 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 Twin Hills Colony reaches the Gulf of America by way of the Marias, the Missouri and the Mississippi: about 3,300 river miles.
Lakes on the way: Lake Oahe, Lake Sakakawea, Lake Fort Peck and Lake Sharpe.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Twin Hills Colony; river miles along the main stem, rounded.
Twin Hills Colony has a cold semi-arid climate. Summer afternoons average 85° in July; winter nights fall to about 13° in January. A normal year brings about 42 inches of snow; with the rain, that comes to about 14 inches of water.
On November 14 Twin Hills Colony normally reaches 43° and falls to 23°. The record high is 72°, in 1999; the record low 5°, in 1997. The most rain on this date, 0.15 in, fell in 1986.
Normals 1991–2020 and records since 1982 at Carter 14 W, 17 miles south-southwest, 150 ft higher. NOAA, through RCC-ACIS.
