The King Arthur Park 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.
−15° on Nov. 13, 2014, the coldest reading for this week of the year since 1966. Next is −14° in 1986.
King Arthur Park’s center stands about 4,830 ft above sea level. Within three miles the land runs from 4,640 ft to 5,070 ft, a difference of 430 ft: hilly country. The highest named summit within 15 miles is Saddle Peak, about 9,110 ft, 13 miles northeast.
The section below crosses 7 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 6×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Age: Pleistocene to Holocene, less than 1.8 million years old. About 12 mi of the line.
Unconsolidated. Age: Pleistocene to Holocene, less than 1.8 million years old. About 4 mi of the line.
Gneiss. Age: Archean. About 3 mi of the line.
Conglomerate, sandstone, siltstone. Age: Early Miocene to Pliocene, 2.6 to 20 million years old. About 3 mi of the line.
Andesite, dacite. Age: Early Eocene, 48 to 56 million years old. About 1 mi of the line.
Limestone. Age: Early Mississippian to Middle Mississippian, 331 to 359 million years old. About 0.7 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 1 smaller unit along the line are not listed.
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 King Arthur Park reaches the Gulf of America by way of Hyalite Creek, the East Gallatin, the Gallatin, the Missouri and the Mississippi: about 3,520 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 King Arthur Park; river miles along the main stem, rounded.
King Arthur Park has a warm-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 15° in January. About 16 inches of rain fall in a normal year.
On November 14 King Arthur Park normally reaches 43° and falls to 23°. The record high is 67°, in 2025; the record low −7°, in 1978. The most rain on this date, 0.78 in, fell in 1996.
Normals 1991–2020 and records since 1966 at Bozeman 6 W Experiment Farm, here. NOAA, through RCC-ACIS.