The Dorchester 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
Mostly sunny
Partly cloudy
Mostly sunny
Partly cloudy
Showers likely
79° on Nov. 15, 2025, the hottest reading for this week of the year since 1925. Next is 78° in 2016.
Dorchester’s center stands about 1,490 ft above sea level. Within three miles the land runs from 1,400 ft to 1,510 ft, a difference of 110 ft: gently rolling country.
Under the town center the state geologic map shows Dakota Group (sandstone, shale), from the Early Cretaceous, 100 to 145 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 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.
Sandstone, shale. Age: Early Cretaceous, 100 to 145 million years old. About 16 mi of the line.
Shale, limestone. Age: Late Cretaceous, 66 to 100 million years old. About 8 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 Dorchester reaches the Gulf of America by way of Otoe Creek, the Big Blue, the Kansas, the Missouri and the Mississippi: about 1,870 river miles.
Lake on the way: Tuttle Creek Lake.
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 Dorchester; river miles along the main stem, rounded.
Dorchester has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 12° in January. A normal year brings about 24 inches of snow; with the rain, that comes to about 29 inches of water.
Normals 1991–2020 and records since 1925 at Friend 3 E, 6 miles west. NOAA, through RCC-ACIS.
