The Iola 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.
Partly cloudy
Showers likely; cooler
Chance of showers
Sunny; warmer
Partly cloudy
Partly cloudy
Partly cloudy
21° on Nov. 13, 2014, the coldest reading for this week of the year since 1918. Next is 22° in 1950.
Iola’s center stands about 340 ft above sea level. Within three miles the land runs from 270 ft to 360 ft, a difference of 90 ft: gently rolling country.
Under the town center the state geologic map shows Yegua Formation (claystone, sandstone), from the Eocene, 34 to 56 million years old.
The section below crosses 9 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.
Claystone, sandstone. Age: Eocene, 34 to 56 million years old. About 9 mi of the line.
Fine-detrital, coarse-detrital. Age: Holocene, less than 12,000 years old. About 5 mi of the line.
Sandstone-mudstone. Age: Late Eocene, 34 to 38 million years old. About 3 mi of the line.
Sandstone. Age: Late Eocene, 34 to 38 million years old. About 3 mi of the line.
Claystone, sandstone. Age: Eocene, 34 to 56 million years old. About 1 mi of the line.
Clay, sand. Age: Late Eocene to Early Oligocene, 28 to 38 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. 3 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 Iola reaches the Gulf of America by way of Ragan Creek, the Navasota and the Brazos: about 290 river miles.
230 miles of the trip are on the Brazos.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Iola; river miles along the main stem, rounded.
Iola has a humid subtropical climate. Summer afternoons average 96° in August; winter nights fall to about 37° in January. About 47 inches of rain fall in a normal year.
On November 14 Iola normally reaches 71° and falls to 45°. The record high is 90°, in 1955; the record low 23°, in 2019. The most rain on this date, 3.00 in, fell in 2000.
Normals 1991–2020 and records since 1918 at Madisonville, 15 miles northeast. NOAA, through RCC-ACIS.
