The Elgin 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.
71° on Nov. 17, 1941, the hottest reading for this week of the year since 1893. Next is 71° in 2012.
Elgin’s center stands about 820 ft above sea level. Within three miles the land runs from 790 ft to 1,170 ft, a difference of 380 ft: rolling country. The highest named summit within 15 miles is Corn Hill, about 1,210 ft, 12 miles south-southwest.
Under the town center the state geologic map shows Galena Group and Platteville Formation (dolostone, limestone), from the Late Ordovician, 447 to 459 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 40×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dolostone, limestone. Age: Late Ordovician, 447 to 459 million years old. About 11 mi of the line.
Shale, dolostone. Age: Late Ordovician, 447 to 454 million years old. About 6 mi of the line.
Limestone, dolostone. Age: Middle Devonian to Late Devonian, 374 to 388 million years old. About 4 mi of the line.
Dolostone, limestone. Age: Middle Devonian, 384 to 394 million years old. About 2 mi of the line.
Limestone. Age: Silurian, 440 to 445 million years old. About 1 mi of the line.
Dolostone. Age: Late Ordovician to Silurian, 434 to 447 million years old. About 0.4 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 Elgin reaches the Gulf of America by way of Otter Creek, the Turkey and the Mississippi: about 1,640 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Elgin; river miles along the main stem, rounded.
Elgin has a hot-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 7° in January. A normal year brings about 40 inches of snow; with the rain, that comes to about 39 inches of water.
On November 14 Elgin normally reaches 45° and falls to 26°. The record high is 69°, in 1990; the record low −5°, in 1916. The most rain on this date, 1.17 in, fell in 1902.
Normals 1991–2020 and records since 1893 at Postville, 10 miles north-northeast, 340 ft higher. NOAA, through RCC-ACIS.