The Onekama 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 cloudy
Mostly cloudy; warmer
Mostly sunny
Mostly sunny
Partly cloudy
Chance of showers
Partly cloudy
7° on Nov. 17, 1959, the coldest reading for this week of the year since 1888. Next is 10° in 1911.
Onekama’s center stands about 650 ft above sea level. Within three miles the land runs from 570 ft to 990 ft, a difference of 420 ft: hilly country. The highest named summit within 15 miles is Buck Hills, about 1,150 ft, 15 miles northeast.
Under the town center the state geologic map shows Ellsworth Shale, from the Late Devonian, 359 to 384 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 37×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Shale. Age: Late Devonian, 359 to 384 million years old. About 22 mi of the line.
Black-shale. Age: Late Devonian, 359 to 384 million 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.
Rain that falls on Onekama runs straight into Lake Michigan. 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 Onekama; river miles along the main stem, rounded.
Onekama has a warm-summer humid continental climate. Summer afternoons average 80° in July; winter nights fall to about 19° in January. About 36 inches of rain fall in a normal year.
On November 14 Onekama normally reaches 47° and falls to 34°. The record high is 64°, in 1909; the record low 15°, in 1986. The most rain on this date, 1.38 in, fell in 1957.
Normals 1991–2020 and records since 1888 at Manistee 3 SE, 12 miles south-southwest. NOAA, through RCC-ACIS.
