The Kirby 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
Mostly cloudy
Mostly sunny; warmer
Partly cloudy
Partly cloudy
Partly cloudy
Mostly sunny
5.03 inches of rain fell in two days, the most for this week of the year since records began in 1872. The next wettest, 4.22 inches, fell in 1958.
Kirby’s center stands about 670 ft above sea level. Within three miles the land runs from 540 ft to 980 ft, a difference of 440 ft: hilly country. The highest named summit within 15 miles is Gap Mountain, about 1,880 ft, 12 miles north-northwest.
Under the town center the state geologic map shows Stanley Shale (black-shale, sandstone, siltstone), from the Carboniferous, 324 to 359 million years old.
The section below crosses 6 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 19×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Black-shale, sandstone, siltstone. Age: Carboniferous, 324 to 359 million years old. About 8 mi of the line.
Sandstone, shale. Age: Carboniferous, 299 to 324 million years old. About 7 mi of the line.
Sandstone, shale. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Novaculite. Age: Late Devonian to Carboniferous, 324 to 384 million years old. About 3 mi of the line.
Sandstone. Age: Silurian, 422 to 445 million years old. About 1 mi of the line.
Shale. Age: Carboniferous, 299 to 324 million years old. About 1 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 Kirby reaches the Gulf of America by way of the Little Missouri, the Ouachita, the Black River, the Red River, the Atchafalaya and the Lower Atchafalaya: about 640 river miles.
310 miles of the trip are on the Ouachita.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Kirby; river miles along the main stem, rounded.
Kirby has a humid subtropical climate. Summer afternoons average 93° in July; winter nights fall to about 31° in January. About 56 inches of rain fall in a normal year.
On November 14 Kirby normally reaches 64° and falls to 40°. The record high is 84°, in 1955; the record low 10°, in 1940. The most rain on this date, 1.82 in, fell in 1947.
Normals 1991–2020 and records since 1872 from the Mount Ida Area threaded record (Mount Ida, 21 miles north). NOAA, through RCC-ACIS.
