The South Williamson 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; warmer
Mostly sunny
Partly cloudy
Partly cloudy
Mostly sunny
Mostly sunny
18° on Nov. 15, 2014, the coldest reading for this week of the year since 1951. Next is 22° in 1996.
South Williamson’s center stands about 680 ft above sea level. Within three miles the land runs from 650 ft to 1,650 ft, a difference of 1,000 ft: steep hill country. The highest named summit within 15 miles is Dicks Knob, about 2,490 ft, 12 miles south-southeast.
Under the town center the state geologic map shows Breathitt Formation, lower part (shale, siltstone), from the Carboniferous, 299 to 324 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 13×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone. Age: Carboniferous, 299 to 324 million years old. About 12 mi of the line.
Shale, siltstone. Age: Carboniferous, 299 to 324 million years old. About 6 mi of the line.
Sandstone, shale. Age: Carboniferous, 299 to 324 million years old. About 6 mi of the line.
Sandstone, siltstone, shale. Age: Carboniferous, 299 to 324 million years old. About 0.4 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 South Williamson reaches the Gulf of America by way of the Tug Fork, the Ohio and the Mississippi: about 1,710 river miles.
970 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of South Williamson; river miles along the main stem, rounded.
South Williamson has a humid subtropical climate. Summer afternoons average 89° in July; winter nights fall to about 26° in January. A normal year brings about 13 inches of snow; with the rain, that comes to about 48 inches of water.
Normals 1991–2020 and records since 1951 at Williamson, here. NOAA, through RCC-ACIS.
