The Arthur 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.
74° on Nov. 15, 1953, the hottest reading for this week of the year since 1931. Next is 74° in 2001.
Arthur’s center stands about 1,150 ft above sea level. Within three miles the land runs from 1,110 ft to 1,180 ft, a difference of 70 ft: gently rolling country.
Under the town center the state geologic map shows Undifferentiated (conglomerate, sandstone, mudstone), from the Late Cretaceous, 72 to 100 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 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.
Conglomerate, sandstone, mudstone. Age: Late Cretaceous, 72 to 100 million years old. About 15 mi of the line.
Tonalite, granodiorite, diorite. Age: Neoarchean, 2.5 to 2.8 billion years old. About 5 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 million years old. About 3 mi of the line.
Shale, bentonite. Age: Late Cretaceous, 66 to 100 million years old. About 0.4 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.
Arthur straddles the Laurentian Divide. Rain on the west side runs to the Gulf of America; most of the rest goes to Hudson Bay.
From the center of town, a raindrop reaches Hudson Bay by way of Lake Traverse, the Bois de Sioux, the Red River of the North and the Nelson: about 1,250 river miles. Past the border it runs north through Canada to Hudson Bay. One that lands on the west side reaches the Gulf of America by way of Big Stone Lake, the Minnesota and the Mississippi: about 2,180 river miles.
Lakes on the way: Lake Traverse and Lake Winnipeg.
550 miles of the trip are on the Red River of the North.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Arthur; river miles along the main stem, rounded.
Arthur has a warm-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 4° in January. A normal year brings about 36 inches of snow; with the rain, that comes to about 23 inches of water.
On November 14 Arthur normally reaches 42° and falls to 23°. The record high is 69°, in 1990; the record low −7°, in 2014. The most rain on this date, 0.86 in, fell in 1947.
Normals 1991–2020 and records since 1931 from the Sisseton Area threaded record (Sisseton Municipal Airport, 14 miles west). NOAA, through RCC-ACIS.