The Oelwein 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.
Sunny
Mostly sunny; warmer
Partly cloudy
Mostly sunny
Partly cloudy
Mostly sunny
Showers likely
73° on Nov. 14, 1999, the hottest reading for this week of the year since 1893. Next is 73° in 2012.
Oelwein’s center stands about 1,040 ft above sea level. Within three miles the land runs from 990 ft to 1,180 ft, a difference of 190 ft: gently rolling country. The highest named summit within 15 miles is Corn Hill, about 1,210 ft, 13 miles northeast.
Under the town center the state geologic map shows Hopkinton, Blanding, Tete Des Morts, Mosalem formations (dolostone), from the Late Ordovician to Silurian, 434 to 447 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 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. Age: Late Ordovician to Silurian, 434 to 447 million years old. About 11 mi of the line.
Limestone, dolostone. Age: Middle Devonian to Late Devonian, 374 to 388 million years old. About 6 mi of the line.
Dolostone, limestone. Age: Middle Devonian, 384 to 394 million years old. About 6 mi of the line.
Shale, dolostone. Age: Late Ordovician, 447 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 Oelwein reaches the Gulf of America by way of Otter Creek, the Wapsipinicon and the Mississippi: about 1,660 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Oelwein; river miles along the main stem, rounded.
Oelwein has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 6° in January. A normal year brings about 41 inches of snow; with the rain, that comes to about 40 inches of water.
On November 14 Oelwein normally reaches 45° and falls to 25°. The record high is 73°, in 1999; the record low −3°, in 1916. The most rain on this date, 1.68 in, fell in 1927.
Normals 1991–2020 and records since 1893 at Fayette, 15 miles north-northeast, 100 ft higher. NOAA, through RCC-ACIS.
