The Olney 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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Mostly sunny; warmer
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4° on Nov. 12, 2019, the coldest reading for this week of the year since 1995. Next is 10° in 1997.
Olney’s center stands about 490 ft above sea level. Within three miles the land runs from 420 ft to 560 ft, a difference of 140 ft: gently rolling country. The highest named summit within 15 miles is Red Hill, about 680 ft, 13 miles east.
Under the town center the state geologic map shows Mattoon Formation (shale), from the Late Pennsylvanian, 304 to 307 million years old.
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.
Shale. Age: Late Pennsylvanian, 304 to 307 million years old. About 24 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 Olney reaches the Gulf of America by way of the Fox River, the Little Wabash, the Ohio and the Mississippi: about 1,240 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 Olney; river miles along the main stem, rounded.
Olney 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 46 inches of water.
On November 14 Olney normally reaches 54° and falls to 35°. The record high is 75°, in 2025; the record low 16°, in 2018. The most rain on this date, 0.88 in, fell in 2020.
Normals 1991–2020 and records since 1995 at Newton, 19 miles north-northwest. NOAA, through RCC-ACIS.
