The Walnut 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.
Sunny
Partly cloudy; warmer
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15° on Nov. 13, 2019, the coldest reading for this week of the year since 1895. Next is 17° in 1940.
Walnut’s center stands about 470 ft above sea level. Within three miles the land runs from 400 ft to 590 ft, a difference of 190 ft: gently rolling country. The highest named summit within 15 miles is Wicker Mountain, about 760 ft, 11 miles south-southwest.
Under the town center the state geologic map shows Prairie Bluff chalk and Owl Creek formation (chalk, clay), from the Late Cretaceous, 66 to 100 million years old.
The section below crosses 10 rock units mapped at the surface.
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.
Clay. Age: Paleocene, 56 to 66 million years old. About 8 mi of the line.
Limestone. Age: Paleocene, 56 to 66 million years old. About 3 mi of the line.
Fine-detrital, coarse-detrital. Age: Quaternary, less than 2.6 million years old. About 3 mi of the line.
Sand. Age: Cretaceous, 66 to 145 million years old. About 2 mi of the line.
Sand, clay. Age: Eocene, 34 to 56 million years old. About 2 mi of the line.
Chalk, clay. 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. 4 smaller units along the line are not listed.
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 Walnut reaches the Gulf of America by way of Muddy Creek, the Hatchie, Porters Creek, Cypress Creek and the Mississippi: about 970 river miles.
800 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Walnut; river miles along the main stem, rounded.
Walnut has a humid subtropical climate. Summer afternoons average 90° in July; winter nights fall to about 30° in January. About 59 inches of rain fall in a normal year.
On November 14 Walnut normally reaches 62° and falls to 38°. The record high is 84°, in 1955; the record low 19°, in 2019. The most rain on this date, 3.64 in, fell in 1957.
Normals 1991–2020 and records since 1895 at Corinth 5 WSW, 17 miles east. NOAA, through RCC-ACIS.
