The Grafton 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.
75° on Nov. 11, 2022, the hottest reading for this week of the year since 1944. Next is 71° in 1971.
Grafton’s center stands about 770 ft above sea level. Within three miles the land runs from 670 ft to 880 ft, a difference of 210 ft: rolling country.
Under the town center the state geologic map shows Silurian, undivided (dolostone), from the Silurian, 422 to 445 million years old.
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 45×. 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 14 mi of the line.
Shale, dolostone. Age: Ordovician, 445 to 487 million 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 Grafton reaches Lake Michigan by way of the Milwaukee and the Kinnickinnic: about 30 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 Grafton; river miles along the main stem, rounded.
Grafton has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 11° in January. A normal year brings about 54 inches of snow; with the rain, that comes to about 34 inches of water.
On November 14 Grafton normally reaches 46° and falls to 28°. The record high is 68°, in 1989; the record low 1°, in 1986. The most rain on this date, 0.91 in, fell in 1957.
Normals 1991–2020 and records since 1944 at Germantown Wastewater Utility, 10 miles west-southwest, 100 ft higher. NOAA, through RCC-ACIS.