The Purple Sage 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.
Mostly sunny
Partly cloudy
Partly cloudy
Showers likely
Partly cloudy; cooler
Chance of showers
Showers likely
−15° on Nov. 16, 1955, the coldest reading for this week of the year since 1897. Next is −10° in 1916.
Purple Sage’s center stands about 6,230 ft above sea level. Within three miles the land runs from 6,180 ft to 7,570 ft, a difference of 1,390 ft: steep hill country. The highest named summit within 15 miles is Quaking Asp Mountain, about 8,660 ft, 13 miles southeast.
Under the town center the state geologic map shows Wasatch Formation - Main Body (claystone, siltstone), from the Paleocene to Eocene, 34 to 66 million years old.
The section below crosses 8 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 11×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Oil-shale, marlstone. Age: Eocene, 34 to 56 million years old. About 11 mi of the line.
Sandstone, shale, claystone. Age: Late Cretaceous, 66 to 100 million years old. About 6 mi of the line.
Claystone, siltstone. Age: Paleocene to Eocene, 34 to 66 million years old. About 3 mi of the line.
Sandstone, shale. Age: Paleocene, 56 to 66 million years old. About 1 mi of the line.
Sandstone. Age: Miocene, 5.3 to 23 million years old. About 1 mi of the line.
Sandstone, shale, marlstone. Age: Eocene, 34 to 56 million years old. About 1 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 2 smaller units 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 Purple Sage reaches the Gulf of California by way of Bitter Creek, the Green River and the Colorado: about 1,490 river miles.
Lakes on the way: Lake Mead, Lake Powell, Flaming Gorge Reservoir and Lake Mohave.
410 miles of the trip are on the Green River.
Seldom reaches the sea. Dams and canals now take nearly all of the Colorado before its old delta in Mexico.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Purple Sage; river miles along the main stem, rounded.
Purple Sage has a cold semi-arid climate. Summer afternoons average 87° in July; winter nights fall to about 8° in January. A normal year brings about 38 inches of snow; with the rain, that comes to about 10 inches of water.
On November 14 Purple Sage normally reaches 44° and falls to 20°. The record high is 66°, in 2025; the record low −8°, in 1916. The most rain on this date, 0.50 in, fell in 1928.
Normals 1991–2020 and records since 1897 at Green River, 8 miles west-southwest. NOAA, through RCC-ACIS.
