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
Mostly sunny; warmer
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10° on Nov. 17, 1959, the coldest reading for this week of the year since 1946. Next is 10° in 2019.
St. Charles’s center stands about 510 ft above sea level. Within three miles the land runs from 420 ft to 670 ft, a difference of 250 ft: rolling country. The highest named summit within 15 miles is Flat Knob, about 740 ft, 11 miles west-southwest.
Under the town center the state geologic map shows Carbondale Formation (siltstone), from the Carboniferous, 299 to 324 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 63×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Siltstone. Age: Carboniferous, 299 to 324 million years old. About 7 mi of the line.
Siltstone. Age: Carboniferous, 299 to 324 million years old. About 7 mi of the line.
Sand, silt. Age: Pleistocene to Holocene, less than 2.6 million years old. About 3 mi of the line.
Siltstone. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Sandstone. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Limestone, sandstone. Age: Carboniferous, 324 to 359 million years old. About 0.7 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 St. Charles reaches the Gulf of America by way of Caney Creek, the Tradewater, the Ohio and the Mississippi: about 1,180 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 St. Charles; river miles along the main stem, rounded.
St. Charles has a humid subtropical climate. Summer afternoons average 89° in July; winter nights fall to about 28° in January. About 52 inches of rain fall in a normal year.
On November 14 St. Charles normally reaches 59° and falls to 40°. The record high is 77°, in 1990; the record low 12°, in 1986. The most rain on this date, 3.70 in, fell in 1957.
Normals 1991–2020 and records since 1946 at Madisonville, 11 miles north. NOAA, through RCC-ACIS.
