The Ahnapee 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.
2° on Nov. 17, 1959, the coldest reading for this week of the year since 1905. Next is 4° in 1933.
Ahnapee’s center stands about 610 ft above sea level. Within three miles the land runs from 570 ft to 720 ft, a difference of 150 ft: gently rolling country. The highest named summit within 15 miles is Dhuey Hill, about 950 ft, 8 miles west.
Under the town center the state geologic map shows Silurian, undivided (dolostone), from the Silurian, 422 to 445 million years old.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 61×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dolostone. Age: Silurian, 422 to 445 million years old. About 15 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 Ahnapee reaches Lake Michigan by way of the Ahnapee: about 2 river miles. From there it moves on through the Great Lakes, over Niagara Falls and down the St. Lawrence to the Atlantic.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Ahnapee; river miles along the main stem, rounded.
Ahnapee has a warm-summer humid continental climate. Summer afternoons average 78° in July; winter nights fall to about 10° in January. A normal year brings about 57 inches of snow; with the rain, that comes to about 33 inches of water.
On November 14 Ahnapee normally reaches 43° and falls to 29°. The record high is 67°, in 1999; the record low 9°, in 1986. The most rain on this date, 1.09 in, fell in 1957.
Normals 1991–2020 and records since 1905 at Sturgeon Bay Experiment Farm, 18 miles north-northeast. NOAA, through RCC-ACIS.