The East Chain 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.
Mostly sunny
Partly cloudy; warmer
Mostly sunny
Mostly sunny
Partly cloudy
Partly cloudy
Showers likely
80° on Nov. 14, 1999, the hottest reading for this week of the year since 1954. Next is 75° in 2001.
East Chain’s center stands about 1,170 ft above sea level. Within three miles the land runs from 1,130 ft to 1,200 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 5 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.
Limestone, dolostone. Age: Late Ordovician, 445 to 459 million years old. About 9 mi of the line.
Dolostone, sandstone. Age: Early Ordovician, 471 to 487 million years old. About 7 mi of the line.
Shale, limestone, sandstone. Age: Middle Ordovician to Late Ordovician, 445 to 471 million years old. About 6 mi of the line.
Sandstone, siltstone, shale. Age: Cambrian, 487 to 497 million years old. About 2 mi of the line.
Sandstone, shale. Age: Early Cretaceous to Late Cretaceous, 94 to 113 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 East Chain reaches the Gulf of America by way of Badger Creek, the Blue Earth, the Minnesota and the Mississippi: about 2,050 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of East Chain; river miles along the main stem, rounded.
East Chain has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 4° in January. A normal year brings about 40 inches of snow; with the rain, that comes to about 33 inches of water.
On November 14 East Chain normally reaches 43° and falls to 23°. The record high is 80°, in 1999; the record low −10°, in 1959. The most rain on this date, 1.37 in, fell in 2010.
Normals 1991–2020 and records since 1954 at Swea City 5 N, 8 miles south-southeast. NOAA, through RCC-ACIS.
