The Gillette 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.
75° on Nov. 12, 1999, the hottest reading for this week of the year since 1902. Next is 71° in 1990.
Gillette’s center stands about 4,560 ft above sea level. Within three miles the land runs from 4,400 ft to 4,760 ft, a difference of 360 ft: rolling country. The highest named summit within 15 miles is Antelope Butte, about 5,020 ft, 6 miles south-southeast.
Under the town center the state geologic map shows Wasatch Formation (mudstone, sandstone), from the Eocene, 34 to 56 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 23×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Mudstone, sandstone. Age: Eocene, 34 to 56 million years old. About 22 mi of the line.
Clay, silt, sand. Age: Pleistocene to Holocene, less than 2.6 million years old. About 1 mi of the line.
Sandstone, shale. Age: Paleocene, 56 to 66 million years old. About 0.8 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 Gillette reaches the Gulf of America by way of Donkey Creek, the Belle Fourche, the Cheyenne, the Missouri and the Mississippi: about 2,800 river miles.
Lakes on the way: Lake Oahe, Lake Sharpe, Lake Francis Case and Lewis and Clark 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 Gillette; river miles along the main stem, rounded.
Gillette has a warm-summer humid continental climate. Summer afternoons average 86° in July; winter nights fall to about 16° in January. A normal year brings about 56 inches of snow; with the rain, that comes to about 18 inches of water.
On November 14 Gillette normally reaches 47° and falls to 25°. The record high is 73°, in 1999; the record low −16°, in 1959. The most rain on this date, 0.63 in, fell in 1964.
Normals 1991–2020 and records since 1902 at Gillette 3 SE, 3 miles east-southeast. NOAA, through RCC-ACIS.