The McHenry 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
Mostly sunny
Mostly sunny
Partly cloudy
Partly cloudy
Partly cloudy
78° on Nov. 11, 2022, the hottest reading for this week of the year since 1948. Next is 74° in 2020.
McHenry’s center stands about 800 ft above sea level. Within three miles the land runs from 730 ft to 870 ft, a difference of 140 ft: gently rolling country. The highest named summit within 15 miles is Gander Mountain, about 960 ft, 12 miles north-northeast.
The section below crosses 2 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.
Dolostone, limestone. Age: Silurian, 422 to 445 million years old. About 23 mi of the line.
Shale, limestone. Age: Late Ordovician, 445 to 454 million years old. About 1 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 McHenry reaches the Gulf of America by way of the Fox River, the Illinois and the Mississippi: about 1,540 river miles.
Lake on the way: Peoria Lake.
1,190 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of McHenry; river miles along the main stem, rounded.
McHenry has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 13° in January. A normal year brings about 34 inches of snow; with the rain, that comes to about 37 inches of water.
On November 14 McHenry normally reaches 49° and falls to 30°. The record high is 70°, in 1999; the record low 10°, in 1996. The most rain on this date, 0.59 in, fell in 2024.
Normals 1991–2020 and records since 1948 at Mchenry Stratton Lock/Dam, here. NOAA, through RCC-ACIS.
