The Mountain Lake 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.
80° on Nov. 13, 1999, the hottest reading for this week of the year since 1905. Next is 73° in 2001.
Mountain Lake’s center stands about 1,300 ft above sea level. Within three miles the land runs from 1,250 ft to 1,360 ft, a difference of 110 ft: gently rolling country.
The section below crosses 2 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 52×. 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 19 mi of the line.
Quartzite, mudstone. Age: Paleoproterozoic, 1.6 to 2 billion years old. About 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 Mountain Lake reaches the Gulf of America by way of the South Fork Watonwan, the Watonwan, the Blue Earth, the Minnesota and the Mississippi: about 2,030 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Mountain Lake; river miles along the main stem, rounded.
Mountain Lake has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 8° in January. A normal year brings about 44 inches of snow; with the rain, that comes to about 32 inches of water.
On November 14 Mountain Lake normally reaches 44° and falls to 26°. The record high is 68°, in 1953; the record low −13°, in 1959. The most rain on this date, 1.53 in, fell in 1909.
Normals 1991–2020 and records since 1905 at Windom, 10 miles west. NOAA, through RCC-ACIS.