The St. Charles 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
3.60 inches of rain fell in two days, the most for this week of the year since records began in 1893. The next wettest, 2.76 inches, fell in 1913.
St. Charles’s center stands about 550 ft above sea level. Within three miles the land runs from 420 ft to 610 ft, a difference of 190 ft: gently rolling country. The highest named summit within 15 miles is Tucker Knob, about 890 ft, 13 miles north.
Under the town center the state geologic map shows Meramecian Series (limestone), from the Carboniferous, 324 to 359 million years old.
The section below crosses 5 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.
Clay, silt, sand. Age: Holocene, less than 12,000 years old. About 13 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 3 mi of the line.
Shale, sandstone, siltstone. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Limestone, shale. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Shale, sandstone. Age: Carboniferous, 299 to 324 million years old. About 2 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 St. Charles reaches the Gulf of America by way of Cole Creek, Dardenne Creek and the Mississippi: about 1,210 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of St. Charles; river miles along the main stem, rounded.
St. Charles has a hot-summer humid continental climate. Summer afternoons average 88° in July; winter nights fall to about 22° in January. A normal year brings about 9 inches of snow; with the rain, that comes to about 46 inches of water.
On November 14 St. Charles normally reaches 56° and falls to 36°. The record high is 83°, in 1955; the record low 11°, in 1986. The most rain on this date, 2.21 in, fell in 1913.
Normals 1991–2020 and records since 1893 at St Charles Elm Point, here. NOAA, through RCC-ACIS.
