The Ionia 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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Showers likely
81° on Nov. 17, 2016, the hottest reading for this week of the year since 1900. Next is 78° in 1952.
Ionia’s center stands about 1,540 ft above sea level. Within three miles the land runs from 1,510 ft to 1,650 ft, a difference of 140 ft: gently rolling country.
Under the town center the state geologic map shows Alluvium (sand, silt, clay), from the Pleistocene to Holocene, less than 2.6 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 50×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Silt. Age: Pleistocene to Holocene, less than 2.6 million years old. About 12 mi of the line.
Sand, silt, clay. Age: Pleistocene to Holocene, less than 2.6 million years old. About 6 mi of the line.
Shale, limestone. Age: Late Cretaceous, 66 to 100 million years old. About 3 mi of the line.
Shale, chalk. Age: Late Cretaceous, 66 to 100 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 Ionia reaches the Gulf of America by way of Limestone Creek, the Solomon, the Smoky Hill, the Kansas, the Missouri and the Mississippi: about 1,960 river miles.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Ionia; river miles along the main stem, rounded.
Ionia has a hot-summer humid continental climate. Summer afternoons average 88° in July; winter nights fall to about 14° in January. A normal year brings about 24 inches of snow; with the rain, that comes to about 28 inches of water.
On November 14 Ionia normally reaches 53° and falls to 26°. The record high is 75°, in 2025; the record low −1°, in 1940. The most rain on this date, 1.46 in, fell in 1926.
Normals 1991–2020 and records since 1900 at Burr Oak 4 S, 10 miles north-northeast, 200 ft higher. NOAA, through RCC-ACIS.
