The Lake Hanska 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.
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Mostly sunny; warmer
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Showers likely
81° on Nov. 14, 1999, the hottest reading for this week of the year since 1940. Next is 75° in 2015.
Lake Hanska’s center stands about 1,010 ft above sea level. Within three miles the land runs from 990 ft to 1,050 ft, a difference of 60 ft: nearly flat ground.
Under the town center the state geologic map shows Claystone, siltstone, and sandstone (claystone, siltstone, sandstone), from the Early Cretaceous, 100 to 113 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 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.
Sandstone, siltstone, shale. Age: Middle Cambrian to Cambrian, 487 to 521 million years old. About 9 mi of the line.
Claystone, siltstone, sandstone. Age: Early Cretaceous, 100 to 113 million years old. About 8 mi of the line.
Conglomerate, sandstone, mudstone. Age: Late Cretaceous, 72 to 100 million years old. About 6 mi of the line.
Quartzite, mudstone. Age: Paleoproterozoic, 1.6 to 2 billion years old. About 1 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 Lake Hanska reaches the Gulf of America by way of Morgan Creek, the Minnesota and the Mississippi: about 1,980 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Lake Hanska; river miles along the main stem, rounded.
Lake Hanska has a hot-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 5° in January. A normal year brings about 50 inches of snow; with the rain, that comes to about 33 inches of water.
On November 14 Lake Hanska normally reaches 44° and falls to 25°. The record high is 81°, in 1999; the record low −8°, in 1959. The most rain on this date, 0.85 in, fell in 1944.
Normals 1991–2020 and records since 1940 at St. James Wwtp, 13 miles south-southwest. NOAA, through RCC-ACIS.
