The Rock Falls 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.
Mostly sunny
Mostly sunny; warmer
Partly cloudy
Partly cloudy
Partly cloudy
Chance of showers
Showers likely
71° on Nov. 17, 1953, the hottest reading for this week of the year since 1905. Next is 69° in 1909.
Rock Falls’s center stands about 1,580 ft above sea level. Within three miles the land runs from 1,360 ft to 1,620 ft, a difference of 260 ft: rolling country. The highest named summit within 15 miles is Lookout Mountain, about 1,960 ft, 14 miles east-northeast.
Under the town center the state geologic map shows Granodiorite-tonalite (granodiorite, tonalite), from the Paleoproterozoic, 1.8 to 1.8 billion 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 44×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Granodiorite, tonalite. Age: Paleoproterozoic, 1.8 to 1.8 billion years old. About 10 mi of the line.
Metavolcanic. Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 9 mi of the line.
Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 5 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 Rock Falls reaches the Gulf of America by way of Ripley Creek, the Wisconsin and the Mississippi: about 1,910 river miles.
Lakes on the way: Petenwell Lake, Lake Wisconsin, Lake Du Bay and Wisconsin River Flowage 4964.
1,610 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Rock Falls; river miles along the main stem, rounded.
Rock Falls has a warm-summer humid continental climate. Summer afternoons average 80° in July; winter nights fall to about 3° in January. A normal year brings about 54 inches of snow; with the rain, that comes to about 34 inches of water.
On November 14 Rock Falls normally reaches 40° and falls to 24°. The record high is 65°, in 1999; the record low −5°, in 1916. The most rain on this date, 0.83 in, fell in 1909.
Normals 1991–2020 and records since 1905 at Merrill, 10 miles south-southeast, 330 ft lower. NOAA, through RCC-ACIS.
