The Clarkson Valley 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.
Sunny
Partly cloudy; warmer
Sunny
Sunny
Partly cloudy
Partly cloudy
Partly cloudy
10° on Nov. 12, 2019, the coldest reading for this week of the year since 1987. Next is 13° in 2018.
Clarkson Valley’s center stands about 630 ft above sea level. Within three miles the land runs from 500 ft to 760 ft, a difference of 260 ft: rolling country. The highest named summit within 15 miles is Tavern Rock, about 880 ft, 9 miles west.
Under the town center the state geologic map shows Osagean Series (limestone), from the Carboniferous, 324 to 359 million years old.
The section below crosses 6 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 45×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 8 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 7 mi of the line.
Limestone. Age: Middle Ordovician, 459 to 471 million years old. About 5 mi of the line.
Shale, sandstone, siltstone. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Clay, silt, sand. Age: Holocene, less than 12,000 years old. About 0.5 mi of the line.
Dolostone, limestone, shale. Age: Middle Ordovician, 459 to 471 million years old. About 0.3 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 Clarkson Valley reaches the Gulf of America by way of Caulks Creek, Bonhomme Creek, the Missouri and the Mississippi: about 1,210 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Clarkson Valley; river miles along the main stem, rounded.
Clarkson Valley has a hot-summer humid continental climate. Summer afternoons average 90° in July; winter nights fall to about 22° in January. About 40 inches of rain fall in a normal year.
On November 14 Clarkson Valley normally reaches 57° and falls to 35°. The record high is 80°, in 2025; the record low 13°, in 2018. The most rain on this date, 2.08 in, fell in 1993.
Normals 1991–2020 and records since 1987 at St Louis Spirit Of St Louis Airport, 4 miles northwest, 170 ft lower. NOAA, through RCC-ACIS.
