The Iron Ridge 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
Mostly sunny
Mostly sunny
Partly cloudy
Mostly sunny
Chance of showers
−2° on Nov. 12, 1986, the coldest reading for this week of the year since 1970. Next is 5° in 2019.
Iron Ridge’s center stands about 930 ft above sea level. Within three miles the land runs from 860 ft to 1,180 ft, a difference of 320 ft: rolling country. The highest named summit within 15 miles is Holy Hill, about 1,350 ft, 15 miles southeast.
Under the town center the state geologic map shows Maquoketa Formation (shale, dolostone), from the Ordovician, 445 to 487 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 53×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Shale, dolostone. Age: Ordovician, 445 to 487 million years old. About 12 mi of the line.
Dolostone. Age: Ordovician, 445 to 487 million years old. About 9 mi of the line.
Dolostone. Age: Silurian, 422 to 445 million years old. About 3 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 Iron Ridge reaches the Gulf of America by way of Wildcat Creek, the Rock River and the Mississippi: about 1,750 river miles.
Lake on the way: Lake Koshkonong.
1,450 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Iron Ridge; river miles along the main stem, rounded.
Iron Ridge has a warm-summer humid continental climate. Summer afternoons average 80° in July; winter nights fall to about 9° in January. A normal year brings about 41 inches of snow; with the rain, that comes to about 35 inches of water.
On November 14 Iron Ridge normally reaches 44° and falls to 27°. The record high is 71°, in 1971; the record low 7°, in 1996. The most rain on this date, 0.90 in, fell in 1980.
Normals 1991–2020 and records since 1970 at Horicon Wwtp, 6 miles west-northwest. NOAA, through RCC-ACIS.
