The Marion 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; warmer
Mostly sunny
Mostly cloudy
Partly cloudy
Partly cloudy; cooler
Showers likely
−21° on Nov. 14, 1959, the coldest reading for this week of the year since 1948. Next is −8° in 1955.
Marion’s center stands about 1,450 ft above sea level. Within three miles the land runs from 1,350 ft to 1,480 ft, a difference of 130 ft: gently rolling country.
Under the town center the state geologic map shows Niobrara Formation (chalk, marlstone, shale), from the Late Cretaceous, 66 to 100 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Chalk, marlstone, shale. Age: Late Cretaceous, 66 to 100 million years old. About 18 mi of the line.
Quartzite. Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 4 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 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 Marion reaches the Gulf of America by way of the West Fork Vermillion, the Vermillion, the Missouri and the Mississippi: about 2,040 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 Marion; river miles along the main stem, rounded.
Marion has a hot-summer humid continental climate. Summer afternoons average 85° in July; winter nights fall to about 8° in January. About 28 inches of rain fall in a normal year.
On November 14 Marion normally reaches 45° and falls to 24°. The record high is 76°, in 1953; the record low −21°, in 1959. The most rain on this date, 0.31 in, fell in 2024.
Normals 1991–2020 and records since 1948 at Bridgewater, 15 miles northwest. NOAA, through RCC-ACIS.
