The Merwin 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 sunny
Mostly sunny
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Partly cloudy
Partly cloudy
Chance of showers
83° on Nov. 13, 1999, the hottest reading for this week of the year since 1940. Next is 81° in 1952.
Merwin’s center stands about 910 ft above sea level. Within three miles the land runs from 860 ft to 1,040 ft, a difference of 180 ft: gently rolling country.
Under the town center the state geologic map shows Pleasanton Group (shale, sandstone), from the Carboniferous, 299 to 324 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 60×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Limestone, shale. Age: Carboniferous, 299 to 324 million years old. About 9 mi of the line.
Limestone, shale. Age: Carboniferous, 299 to 324 million years old. About 8 mi of the line.
Shale, sandstone. Age: Carboniferous, 299 to 324 million years old. About 6 mi of the line.
Limestone, shale. Age: Carboniferous, 299 to 324 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.
A raindrop that lands in Merwin reaches the Gulf of America by way of the Marais des Cygnes, the Osage, the Missouri and the Mississippi: about 1,620 river miles.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Merwin; river miles along the main stem, rounded.
Merwin has a hot-summer humid continental climate. Summer afternoons average 89° in July; winter nights fall to about 20° in January. A normal year brings about 10 inches of snow; with the rain, that comes to about 44 inches of water.
On November 14 Merwin normally reaches 56° and falls to 34°. The record high is 82°, in 1999; the record low 10°, in 2018. The most rain on this date, 0.98 in, fell in 1993.
Normals 1991–2020 and records since 1940 at Butler 4 W, 14 miles southeast, 120 ft lower. NOAA, through RCC-ACIS.
