The Koosharem 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
Partly cloudy; warmer
Mostly cloudy
Showers likely; cooler
Partly cloudy
Showers likely
Showers likely
72° on Nov. 16, 2016, the hottest reading for this week of the year since 1893. Next is 69° in 2021.
Koosharem’s center stands about 6,930 ft above sea level. Within three miles the land runs from 6,780 ft to 8,190 ft, a difference of 1,410 ft: steep hill country. The highest named summit within 15 miles is Whiskey Knoll, about 11,530 ft, 12 miles northeast.
Under the town center the state geologic map shows Older alluvial deposits (coarse-detrital), from the Quaternary, less than 2.6 million years old.
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 4×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Felsic-volcanic. Age: Late Oligocene to Middle Miocene, 12 to 28 million years old. About 19 mi of the line.
Coarse-detrital. Age: Quaternary, less than 2.6 million years old. About 2 mi of the line.
Unconsolidated. Age: Pliocene to Pleistocene, less than 5.3 million years old. About 1 mi of the line.
Unconsolidated. Age: Quaternary, less than 2.6 million years old. About 0.8 mi of the line.
Felsic-volcanic, andesite. Age: Late Eocene to Oligocene, 23 to 38 million years old. About 0.8 mi of the line.
Basalt. Age: Pliocene, 2.6 to 5.3 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. 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 Koosharem reaches Sevier Lake by way of Otter Creek, the East Fork Sevier and the Sevier: about 360 river miles. Sevier Lake has no outlet to the sea: the water leaves only by evaporating or soaking into the ground.
300 miles of the trip are on the Sevier.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Koosharem; river miles along the main stem, rounded.
Koosharem has a cold semi-arid climate. Summer afternoons average 84° in July; winter nights fall to about 9° in January. A normal year brings about 19 inches of snow; with the rain, that comes to about 8 inches of water.
On November 14 Koosharem normally reaches 51° and falls to 18°. The record high is 68°, in 1967; the record low 0°, in 1938. The most rain on this date, 0.37 in, fell in 1987.
Normals 1991–2020 and records since 1893 at Loa, 15 miles east-southeast, 140 ft higher. NOAA, through RCC-ACIS.
