The Delavan 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.
Partly cloudy
Partly cloudy; warmer
Mostly sunny
Partly cloudy
Mostly cloudy
Partly cloudy
Showers likely
80° on Nov. 14, 1999, the hottest reading for this week of the year since 1898. Next is 75° in 2012.
Delavan’s center stands about 1,070 ft above sea level. Within three miles the land runs from 1,030 ft to 1,100 ft, a difference of 70 ft: gently rolling country.
Under the town center the state geologic map shows Middle and Upper Ordovician (shale, limestone, sandstone), from the Middle Ordovician to Late Ordovician, 445 to 471 million years old.
The section below crosses 3 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.
Shale, limestone, sandstone. Age: Middle Ordovician to Late Ordovician, 445 to 471 million years old. About 12 mi of the line.
Limestone, dolostone. Age: Late Ordovician, 445 to 459 million years old. About 7 mi of the line.
Dolostone, sandstone. Age: Early Ordovician, 471 to 487 million years old. About 5 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 Delavan reaches the Gulf of America by way of Rice Creek, the Maple, the Le Sueur, the Blue Earth, the Minnesota and the Mississippi: about 1,990 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Delavan; river miles along the main stem, rounded.
Delavan has a hot-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 6° in January. A normal year brings about 47 inches of snow; with the rain, that comes to about 34 inches of water.
On November 14 Delavan normally reaches 43° and falls to 26°. The record high is 80°, in 1999; the record low −7°, in 1940. The most rain on this date, 1.26 in, fell in 1909.
Normals 1991–2020 and records since 1898 at Winnebago, 7 miles west. NOAA, through RCC-ACIS.
