The Sioux Agency 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
Mostly cloudy
Partly cloudy
Showers likely
78° on Nov. 13, 1999, the hottest reading for this week of the year since 1892. Next is 75° in 1953.
Sioux Agency’s center stands about 1,040 ft above sea level. Within three miles the land runs from 910 ft to 1,080 ft, a difference of 170 ft: gently rolling country.
Under the town center the state geologic map shows Granitic intrusion, from the Neoarchean, 2.5 to 2.8 billion years old.
The section below crosses 7 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.
Orthogneiss, migmatite. Age: Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old. About 13 mi of the line.
Granitic. Age: Neoarchean, 2.5 to 2.8 billion years old. About 4 mi of the line.
Leucocratic-granitic. Age: Neoarchean, 2.5 to 2.8 billion years old. About 3 mi of the line.
Mafic-volcanic, hypabyssal. Age: Archean to Paleoproterozoic. About 2 mi of the line.
Mylonite. Age: Archean. About 1 mi of the line.
Conglomerate, sandstone, mudstone. Age: Late Cretaceous, 72 to 100 million years old. About 0.4 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 1 smaller unit along the line are not listed.
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 Sioux Agency reaches the Gulf of America by way of the Minnesota and the Mississippi: about 2,060 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Sioux Agency; river miles along the main stem, rounded.
Sioux Agency has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 6° in January. About 28 inches of rain fall in a normal year.
On November 14 Sioux Agency normally reaches 43° and falls to 25°. The record high is 74°, in 2025; the record low −8°, in 1959. The most rain on this date, 1.53 in, fell in 1909.
Normals 1991–2020 and records since 1892 at Redwood Falls Municipal Airport, 20 miles east-southeast. NOAA, through RCC-ACIS.
