The Rockford 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.
Partly cloudy
Partly cloudy
Mostly sunny
Partly cloudy
Mostly sunny
Partly cloudy
Mostly sunny
7° on Nov. 17, 1959, the coldest reading for this week of the year since 1893. Next is 8° in 1916.
Rockford’s center stands about 620 ft above sea level. Within three miles the land runs from 550 ft to 650 ft, a difference of 100 ft: gently rolling country. The highest named summit within 15 miles is Pinnacle, about 960 ft, 10 miles southwest.
Under the town center the state geologic map shows New Albany Shale (black-shale), from the Devonian to Carboniferous, 324 to 422 million years old.
The section below crosses 3 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.
Black-shale. Age: Devonian to Carboniferous, 324 to 422 million years old. About 16 mi of the line.
Siltstone. Age: Carboniferous, 324 to 359 million years old. About 8 mi of the line.
Limestone, dolostone. Age: Devonian, 359 to 422 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.
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 Rockford reaches the Gulf of America by way of the East Fork White, the White River, Big Bayou, the Wabash River Old Channel, the Old Channel Wabash, the Ohio and the Mississippi: about 1,390 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 Rockford; river miles along the main stem, rounded.
Rockford has a hot-summer humid continental climate. Summer afternoons average 86° in July; winter nights fall to about 22° in January. A normal year brings about 16 inches of snow; with the rain, that comes to about 47 inches of water.
On November 14 Rockford normally reaches 55° and falls to 34°. The record high is 83°, in 1955; the record low 11°, in 1986. The most rain on this date, 1.71 in, fell in 1972.
Normals 1991–2020 and records since 1893 at Columbus, 13 miles north. NOAA, through RCC-ACIS.
