The Keystone 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 cloudy
Mostly cloudy
Partly cloudy; warmer
Partly cloudy
Partly cloudy
Mostly sunny
Mostly sunny
13° on Nov. 14, 2019, the coldest reading for this week of the year since 1940. Next is 14° in 2014.
Keystone’s center stands about 1,690 ft above sea level. Within three miles the land runs from 1,610 ft to 2,730 ft, a difference of 1,120 ft: steep hill country. The highest named summit within 15 miles is Bluff Mountain, about 3,550 ft, 15 miles east-northeast.
Under the town center the state geologic map shows Pocahontas Formation (sandstone), from the Carboniferous, 299 to 324 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 9×. 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. Age: Carboniferous, 299 to 324 million years old. About 14 mi of the line.
Sandstone. Age: Carboniferous, 299 to 324 million years old. About 11 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 Keystone reaches the Gulf of America by way of Elkhorn Creek, the Tug Fork, the Ohio and the Mississippi: about 1,800 river miles.
970 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Keystone; river miles along the main stem, rounded.
Keystone has a humid subtropical climate. Summer afternoons average 85° in July; winter nights fall to about 22° in January. About 49 inches of rain fall in a normal year.
On November 14 Keystone normally reaches 57° and falls to 31°. The record high is 81°, in 1993; the record low 13°, in 2019. The most rain on this date, 0.75 in, fell in 2008.
Normals 1991–2020 and records since 1940 at Mullens 3 E, 13 miles north-northeast, 130 ft lower. NOAA, through RCC-ACIS.
