The Charlestown 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
Mostly sunny; warmer
Mostly sunny
Partly cloudy
Partly cloudy
Partly cloudy; cooler
Showers likely
79° on Nov. 14, 1999, the hottest reading for this week of the year since 1961. Next is 75° in 2001.
Charlestown’s center stands about 1,090 ft above sea level. Within three miles the land runs from 1,050 ft to 1,130 ft, a difference of 80 ft: gently rolling country.
Under the town center the state geologic map shows Undifferentiated (conglomerate, sandstone, mudstone), from the Late Cretaceous, 72 to 100 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 47×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Conglomerate, sandstone, mudstone. Age: Late Cretaceous, 72 to 100 million years old. About 14 mi of the line.
Granitic. Age: Neoarchean, 2.5 to 2.8 billion years old. About 5 mi of the line.
Quartzite, mudstone. Age: Paleoproterozoic, 1.6 to 2 billion years old. About 3 mi of the line.
Orthogneiss. Age: Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old. About 2 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 Charlestown reaches the Gulf of America by way of Coal Mine Creek, the Cottonwood, the Minnesota and the Mississippi: about 2,040 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Charlestown; river miles along the main stem, rounded.
Charlestown has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 5° in January. A normal year brings about 46 inches of snow; with the rain, that comes to about 29 inches of water.
On November 14 Charlestown normally reaches 43° and falls to 24°. The record high is 79°, in 1999; the record low −3°, in 1986. The most rain on this date, 0.29 in, fell in 2024.
Normals 1991–2020 and records since 1961 at Lamberton Southwest Research And Outreach Center, 7 miles west. NOAA, through RCC-ACIS.
