The St. Peters 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.
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. Peters’s center stands about 520 ft above sea level. Within three miles the land runs from 420 ft to 620 ft, a difference of 200 ft: gently rolling country. The highest named summit within 15 miles is Tucker Knob, about 890 ft, 15 miles north-northeast.
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 6 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 52×. 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 9 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 7 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 3 mi of the line.
Limestone. Age: Middle Mississippian, 331 to 347 million years old. About 3 mi of the line.
Limestone. Age: Middle Mississippian, 331 to 347 million years old. About 2 mi of the line.
Shale, sandstone. Age: Early Pennsylvanian to Middle Pennsylvanian, 307 to 324 million years old. About 0.8 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. Peters reaches the Gulf of America by way of Spencer 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. Peters; river miles along the main stem, rounded.
St. Peters 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. Peters 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, 5 miles east-northeast. NOAA, through RCC-ACIS.