The Swansea 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
Sunny
Sunny
Partly cloudy
Partly cloudy
Mostly sunny
7° on Nov. 17, 1959, the coldest reading for this week of the year since 1948. Next is 8° in 2019.
Swansea’s center stands about 540 ft above sea level. Within three miles the land runs from 470 ft to 600 ft, a difference of 130 ft: gently rolling country.
Under the town center the state geologic map shows Shelburn-Patoka Formations undivided (shale, limestone), from the Late Pennsylvanian, 304 to 307 million years old.
The section below crosses 7 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.
Shale, limestone. Age: Late Pennsylvanian, 304 to 307 million years old. About 14 mi of the line.
Shale, sandstone, coal. Age: Middle Pennsylvanian to Late Pennsylvanian, 304 to 315 million years old. About 4 mi of the line.
Limestone, sandstone, shale. Age: Middle Mississippian, 331 to 347 million years old. About 3 mi of the line.
Limestone. Age: Middle Mississippian, 331 to 347 million years old. About 2 mi of the line.
Limestone. Age: Middle Mississippian, 331 to 347 million years old. About 0.9 mi of the line.
Limestone. Age: Middle Mississippian, 331 to 347 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. 1 smaller unit 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 Swansea reaches the Gulf of America by way of Richland Creek, the Kaskaskia and the Mississippi: about 1,140 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Swansea; river miles along the main stem, rounded.
Swansea has a humid subtropical climate. Summer afternoons average 90° in July; winter nights fall to about 24° in January. A normal year brings about 11 inches of snow; with the rain, that comes to about 43 inches of water.
On November 14 Swansea normally reaches 59° and falls to 37°. The record high is 82°, in 1999; the record low 11°, in 1986. The most rain on this date, 3.23 in, fell in 1993.
Normals 1991–2020 and records since 1948 at Belleville Siu Research, 8 miles east, 110 ft lower. NOAA, through RCC-ACIS.
