The Swanville 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.
69° on Nov. 17, 1953, the hottest reading for this week of the year since 1892. Next is 67° in 1999.
Swanville’s center stands about 1,190 ft above sea level. Within three miles the land runs from 1,160 ft to 1,330 ft, a difference of 170 ft: gently rolling country. The highest named summit within 15 miles is Tower Hill, about 1,500 ft, 10 miles north-northwest.
Under the town center the state geologic map shows Granitic orthogneiss and migmatite (orthogneiss, migmatite), from the Paleoarchean to Mesoarchean, 2.8 to 3.6 billion 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 58×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Slate, graywacke. Age: Paleoproterozoic, 1.6 to 2 billion years old. About 12 mi of the line.
Schist, slate. Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 12 mi of the line.
Orthogneiss, migmatite. Age: Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old. About 0.8 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 Swanville reaches the Gulf of America by way of the Swan River and the Mississippi: about 1,960 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Swanville; river miles along the main stem, rounded.
Swanville has a warm-summer humid continental climate. Summer afternoons average 79° in July; winter nights fall to about −1° in January. A normal year brings about 54 inches of snow; with the rain, that comes to about 31 inches of water.
On November 14 Swanville normally reaches 38° and falls to 21°. The record high is 68°, in 1953; the record low −5°, in 1955. The most rain on this date, 1.47 in, fell in 1909.
Normals 1991–2020 and records since 1892 at Long Prairie, 13 miles west-northwest, 150 ft higher. NOAA, through RCC-ACIS.