The Mona 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.
73° on Nov. 13, 1999, the hottest reading for this week of the year since 1937. Next is 73° in 2012.
Mona’s center stands about 1,170 ft above sea level. Within three miles the land runs from 1,140 ft to 1,220 ft, a difference of 80 ft: gently rolling country.
Under the town center the state geologic map shows Cedar Valley Group (limestone, dolostone), from the Middle Devonian to Late Devonian, 374 to 388 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.
Limestone, dolostone. Age: Middle Devonian to Late Devonian, 374 to 388 million years old. About 13 mi of the line.
Dolostone, limestone, shale. Age: Middle Devonian to Late Devonian, 359 to 394 million years old. About 11 mi of the line.
Dolostone, limestone, shale. Age: Middle Devonian, 384 to 394 million years old. About 0.3 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 Mona reaches the Gulf of America by way of the Cedar River, the Iowa and the Mississippi: about 1,720 river miles.
1,410 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Mona; river miles along the main stem, rounded.
Mona has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 5° in January. A normal year brings about 43 inches of snow; with the rain, that comes to about 36 inches of water.
On November 14 Mona normally reaches 42° and falls to 25°. The record high is 69°, in 1964; the record low −10°, in 1959. The most rain on this date, 0.37 in, fell in 1973.
Normals 1991–2020 and records since 1937 at Austin Waste Water Treatment Facility, 12 miles north. NOAA, through RCC-ACIS.