The Ann 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.
Mostly sunny
Mostly sunny; warmer
Partly cloudy
Partly cloudy
Mostly cloudy
Partly cloudy
Showers likely
72° on Nov. 14, 1999, the hottest reading for this week of the year since 1904. Next is 70° in 1953.
Ann Lake’s center stands about 1,200 ft above sea level. Within three miles the land runs from 1,090 ft to 1,260 ft, a difference of 170 ft: gently rolling country.
Under the town center the state geologic map shows Interlayered volcanic, volcaniclastic, sedimentary, and hypabyssal intrusive rocks (volcanic, sedimentary, hypabyssal), from the Paleoproterozoic, 1.6 to 2.5 billion years old.
The section below crosses 5 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.
Tonalite, diorite. Age: Paleoproterozoic, 1.6 to 1.8 billion years old. About 12 mi of the line.
Sandstone, siltstone. Age: Mesoproterozoic, 1 to 1.2 billion years old. About 4 mi of the line.
Volcanic, sedimentary, hypabyssal. Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 3 mi of the line.
Granitic. Age: Paleoproterozoic, 1.6 to 1.8 billion years old. About 3 mi of the line.
Granitic. Age: Paleoproterozoic, 1.6 to 2.5 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 Ann Lake reaches the Gulf of America by way of Camp Creek, the Ann, the Snake, the Saint Croix and the Mississippi: about 1,940 river miles.
Lakes on the way: Lake Pepin and Lake Mallalieu 175.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Ann Lake; river miles along the main stem, rounded.
Ann Lake has a warm-summer humid continental climate. Summer afternoons average 80° in July; winter nights fall to about 0° in January. A normal year brings about 52 inches of snow; with the rain, that comes to about 32 inches of water.
On November 14 Ann Lake normally reaches 40° and falls to 23°. The record high is 72°, in 1999; the record low −5°, in 1919. The most rain on this date, 1.02 in, fell in 1909.
Normals 1991–2020 and records since 1904 at Mora, 9 miles southeast, 180 ft lower. NOAA, through RCC-ACIS.
