The Mountville 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.
20° on Nov. 12, 2017, the coldest reading for this week of the year since 1948. Next is 21° in 2023.
Mountville’s center stands about 410 ft above sea level. Within three miles the land runs from 320 ft to 660 ft, a difference of 340 ft: rolling country. The highest named summit within 15 miles is Governor Dick Hill, about 1,190 ft, 14 miles north.
The section below crosses 13 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 29×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Schist, phyllite. Age: Paleozoic, 252 to 542 million years old. About 4 mi of the line.
Limestone. Age: Cambrian to Ordovician, 445 to 542 million years old. About 4 mi of the line.
Shale, siltstone. Age: Ordovician, 445 to 487 million years old. About 3 mi of the line.
Phyllite, mica-schist. Age: Paleozoic, 252 to 542 million years old. About 3 mi of the line.
Limestone, dolostone. Age: Ordovician, 445 to 487 million years old. About 2 mi of the line.
Dolostone. Age: Cambrian, 487 to 542 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. 7 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 Mountville reaches Chesapeake Bay and the Atlantic Ocean by way of Strickler Run and the Susquehanna: about 45 river miles.
Lake on the way: Lake Aldred.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Mountville; river miles along the main stem, rounded.
Mountville has a hot-summer humid continental climate. Summer afternoons average 87° in July; winter nights fall to about 25° in January. A normal year brings about 21 inches of snow; with the rain, that comes to about 46 inches of water.
Normals 1991–2020 and records since 1948 at Safe Harbor Dam, 8 miles south-southeast, 220 ft lower. NOAA, through RCC-ACIS.