The Fort Benton 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
79° on Nov. 12, 1999, the hottest reading for this week of the year since 1894. Next is 77° in 1990.
Fort Benton’s center stands about 2,640 ft above sea level. Within three miles the land runs from 2,610 ft to 2,980 ft, a difference of 370 ft: rolling country. The highest named summit within 15 miles is Shaws Peak, about 3,350 ft, 8 miles east-southeast.
Under the town center the state geologic map shows Alluvium (gravel, sand, silt), from the Pleistocene to Holocene, less than 1.8 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 21×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Shale, limestone, dolostone. Age: Late Cretaceous, 84 to 90 million years old. About 18 mi of the line.
Sandstone, shale, siltstone. Age: Late Cretaceous, 72 to 87 million years old. About 4 mi of the line.
Gravel, sand, silt. Age: Pleistocene to Holocene, less than 1.8 million years old. About 2 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 Fort Benton reaches the Gulf of America by way of the Missouri and the Mississippi: about 3,230 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 Fort Benton; river miles along the main stem, rounded.
Fort Benton has a cold semi-arid climate. Summer afternoons average 86° in July; winter nights fall to about 10° in January. A normal year brings about 38 inches of snow; with the rain, that comes to about 13 inches of water.
On November 14 Fort Benton normally reaches 47° and falls to 21°. The record high is 78°, in 1999; the record low −18°, in 2014. The most rain on this date, 0.75 in, fell in 1901.
Normals 1991–2020 and records since 1894 at Fort Benton, here. NOAA, through RCC-ACIS.
