The Lannon 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.
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Partly cloudy
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75° on Nov. 11, 2022, the hottest reading for this week of the year since 1944. Next is 71° in 1971.
Lannon’s center stands about 910 ft above sea level. Within three miles the land runs from 810 ft to 1,030 ft, a difference of 220 ft: rolling country. The highest named summit within 15 miles is Holy Hill, about 1,350 ft, 11 miles northwest.
Under the town center the state geologic map shows Silurian, undivided (dolostone), from the Silurian, 422 to 445 million years old.
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 34×. 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. Age: Silurian, 422 to 445 million years old. About 21 mi of the line.
Shale, dolostone. Age: Ordovician, 445 to 487 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 Lannon reaches the Gulf of America by way of the Fox River, the Illinois and the Mississippi: about 1,620 river miles.
Lakes on the way: Peoria Lake and Fox 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 Lannon; river miles along the main stem, rounded.
Lannon has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 11° 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 Lannon normally reaches 46° and falls to 28°. The record high is 68°, in 1989; the record low 1°, in 1986. The most rain on this date, 0.91 in, fell in 1957.
Normals 1991–2020 and records since 1944 at Germantown Wastewater Utility, 7 miles north-northeast. NOAA, through RCC-ACIS.
