The Union 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
Partly cloudy
Partly cloudy
Partly cloudy
Showers likely
69° on Nov. 11, 2022, the hottest reading for this week of the year since 1903. Next is 69° in 2023.
Union’s center stands about 1,110 ft above sea level. Within three miles the land runs from 800 ft to 1,170 ft, a difference of 370 ft: rolling country.
Under the town center the state geologic map shows Prairie du Chien Group (dolostone), from the Early Ordovician, 471 to 487 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 34×. 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: Early Ordovician, 471 to 487 million years old. About 15 mi of the line.
Sandstone. Age: Cambrian, 487 to 542 million years old. About 8 mi of the line.
Sandstone, siltstone, shale. Age: Middle Cambrian to Cambrian, 487 to 521 million years old. About 0.5 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 Union reaches the Gulf of America by way of Plum Creek, the Chippewa and the Mississippi: about 1,760 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Union; river miles along the main stem, rounded.
Union has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 4° in January. About 35 inches of rain fall in a normal year.
Normals 1991–2020 and records since 1903 at Durand, 11 miles east, 400 ft lower. NOAA, through RCC-ACIS.
