The Decatur 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
Partly cloudy; warmer
Partly cloudy
Sunny
Partly cloudy
Partly cloudy
Partly cloudy
75° on Nov. 11, 2022, the hottest reading for this week of the year since 1953. Next is 73° in 1989.
Decatur’s center stands about 800 ft above sea level. Within three miles the land runs from 740 ft to 920 ft, a difference of 180 ft: gently rolling country. The highest named summit within 15 miles is Bald Hill, about 1,180 ft, 13 miles southeast.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 56×. 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: Carboniferous, 324 to 359 million years old. About 24 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 Decatur reaches Lake Michigan by way of the Dowagiac and the Saint Joseph: about 70 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 Decatur; river miles along the main stem, rounded.
Decatur has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 16° in January. About 42 inches of rain fall in a normal year.
On November 14 Decatur normally reaches 48° and falls to 31°. The record high is 73°, in 1989; the record low 10°, in 2019. The most rain on this date, 1.32 in, fell in 1957.
Normals 1991–2020 and records since 1953 at Dowagiac 1 W, 12 miles southwest. NOAA, through RCC-ACIS.
