The Shell Valley 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.
Partly cloudy
Mostly sunny; warmer
Partly cloudy
Mostly cloudy
Chance of showers; cooler
Partly cloudy
Chance of showers
−20° on Nov. 11, 1986, the coldest reading for this week of the year since 1945. Next is −18° in 1959.
Shell Valley’s center stands about 1,770 ft above sea level. Within three miles the land runs from 1,680 ft to 2,080 ft, a difference of 400 ft: hilly country.
Under the town center the state geologic map shows Fox Hills Formation (shale, sandstone), from the Late Cretaceous, 66 to 100 million years old.
The section below crosses 2 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 29×. 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, sandstone. Age: Late Cretaceous, 66 to 100 million years old. About 22 mi of the line.
Sandstone, siltstone, claystone. Age: Late Cretaceous, 66 to 100 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 Shell Valley reaches Hudson Bay by way of Wolf Creek, Ox Creek, Willow Creek, the Souris, the Assiniboine, the Red River of the North and the Nelson: about 1,120 river miles. Past the border it runs north through Canada to Hudson Bay.
Lake on the way: Lake Winnipeg.
400 miles of the trip are on the Nelson.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Shell Valley; river miles along the main stem, rounded.
Shell Valley has a warm-summer humid continental climate. Summer afternoons average 79° in July; winter nights fall to about −5° in January. About 20 inches of rain fall in a normal year.
On November 14 Shell Valley normally reaches 36° and falls to 16°. The record high is 63°, in 1953; the record low −18°, in 1959. The most rain on this date, 0.12 in, fell in 1960.
Normals 1991–2020 and records since 1945 at Belcourt Keya Radio, 6 miles east-northeast, 190 ft higher. NOAA, through RCC-ACIS.
