The Harpersville 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
Mostly sunny
Sunny
Mostly sunny
Partly cloudy
Mostly sunny
87° on Nov. 14, 2024, the hottest reading for this week of the year since 1950. Next is 84° in 1958.
Harpersville’s center stands about 460 ft above sea level. Within three miles the land runs from 420 ft to 680 ft, a difference of 260 ft: rolling country. The highest named summit within 15 miles is Signal Mountain, about 1,560 ft, 9 miles west-northwest.
Under the town center the state geologic map shows Knox Group undifferentiated in part (dolostone, limestone), from the Cambrian to Ordovician, 445 to 542 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 18×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dolostone, limestone. Age: Cambrian to Ordovician, 445 to 542 million years old. About 10 mi of the line.
Shale. Age: Carboniferous, 299 to 324 million years old. About 5 mi of the line.
Limestone. Age: Ordovician, 445 to 487 million years old. About 3 mi of the line.
Sandstone, shale, siltstone. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Shale, siltstone, sandstone. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Chert, limestone. Age: Carboniferous, 324 to 359 million years old. About 0.9 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 Harpersville reaches Mobile Bay and the Gulf of America by way of Walthall Branch, the Coosa, the Alabama and the Mobile: about 440 river miles.
Lake on the way: Lay Lake.
310 miles of the trip are on the Alabama.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Harpersville; river miles along the main stem, rounded.
Harpersville has a humid subtropical climate. Summer afternoons average 90° in July; winter nights fall to about 31° in January. About 57 inches of rain fall in a normal year, with about 2 inches of snow.
On November 14 Harpersville normally reaches 65° and falls to 39°. The record high is 87°, in 2024; the record low 17°, in 2019. The most rain on this date, 1.42 in, fell in 1957.
Normals 1991–2020 and records since 1950 at Sylacauga 4 NE, 17 miles southeast. NOAA, through RCC-ACIS.
