The Carroll 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
Partly cloudy; warmer
Partly cloudy
Sunny
Sunny
Mostly sunny
Mostly sunny
76° on Nov. 11, 2020, the hottest reading for this week of the year since 1840. Next is 74° in 2009.
Carroll’s center stands about 600 ft above sea level. Within three miles the land runs from 420 ft to 1,010 ft, a difference of 590 ft: hilly country. The highest named summit within 15 miles is Bowers Mountain, about 2,100 ft, 15 miles west-southwest.
The section below crosses 8 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 17×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Siltstone, mudstone. Age: Late Devonian, 359 to 384 million years old. About 9 mi of the line.
Shale, sandstone. Age: Silurian, 422 to 445 million years old. About 3 mi of the line.
Siltstone. Age: Late Devonian, 359 to 384 million years old. About 3 mi of the line.
Shale. Age: Silurian, 422 to 445 million years old. About 3 mi of the line.
Siltstone, shale. Age: Late Devonian, 359 to 384 million years old. About 3 mi of the line.
Black-shale. Age: Early Devonian to Middle Devonian, 384 to 422 million years old. About 2 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 2 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 Carroll reaches Chesapeake Bay and the Atlantic Ocean by way of Sherman Creek and the Susquehanna: about 100 river miles.
Lake on the way: Lake Aldred.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Carroll; river miles along the main stem, rounded.
Carroll has a hot-summer humid continental climate. Summer afternoons average 86° in July; winter nights fall to about 21° in January. A normal year brings about 28 inches of snow; with the rain, that comes to about 48 inches of water.
Normals 1991–2020 and records since 1840 at Carlisle Water Plant, 8 miles south, 170 ft lower. NOAA, through RCC-ACIS.
