The Nachusa 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
Mostly sunny
Mostly sunny
Partly cloudy
Partly cloudy
Partly cloudy
0° on Nov. 17, 1959, the coldest reading for this week of the year since 1893. Next is 2° in 2019.
Nachusa’s center stands about 790 ft above sea level. Within three miles the land runs from 690 ft to 830 ft, a difference of 140 ft: gently rolling country.
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 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, limestone, dolostone. Age: Middle Ordovician to Late Ordovician, 454 to 468 million years old. About 11 mi of the line.
Dolostone, limestone. Age: Late Ordovician, 447 to 459 million years old. About 6 mi of the line.
Dolostone, limestone. Age: Late Ordovician, 454 to 459 million years old. About 4 mi of the line.
Shale, sandstone. Age: Early Pennsylvanian to Middle Pennsylvanian, 307 to 324 million years old. About 2 mi of the line.
Shale, limestone. Age: Late Ordovician, 445 to 454 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 Nachusa reaches the Gulf of America by way of Threemile Branch, the Rock River and the Mississippi: about 1,550 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Nachusa; river miles along the main stem, rounded.
Nachusa has a hot-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 14° in January. A normal year brings about 31 inches of snow; with the rain, that comes to about 40 inches of water.
On November 14 Nachusa normally reaches 48° and falls to 31°. The record high is 75°, in 1971; the record low 5°, in 1986. The most rain on this date, 1.60 in, fell in 1926.
Normals 1991–2020 and records since 1893 at Dixon Wwtp, 7 miles west, 140 ft lower. NOAA, through RCC-ACIS.
