The Unionville 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.
Partly cloudy
Partly cloudy; warmer
Partly cloudy
Sunny
Partly cloudy
Mostly sunny
Mostly sunny
79° on Nov. 15, 1993, the hottest reading for this week of the year since 1931. Next is 75° in 1973.
Unionville’s center stands about 480 ft above sea level. Within three miles the land runs from 210 ft to 560 ft, a difference of 350 ft: rolling country.
Under the town center the state geologic map shows "Glenarm Wissahickon" formation (mica-schist), from the Paleozoic, 252 to 542 million years old.
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 30×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Mica-schist. Age: Paleozoic, 252 to 542 million years old. About 5 mi of the line.
Schist, gneiss. Age: Paleozoic, 252 to 542 million years old. About 5 mi of the line.
Muscovite-gneiss. Age: Precambrian. About 4 mi of the line.
Schist, phyllite. Age: Paleozoic, 252 to 542 million years old. About 3 mi of the line.
Gneiss. Age: Precambrian. About 2 mi of the line.
Mica-schist, quartzite. Age: Paleozoic, 252 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 Unionville reaches Delaware Bay and the Atlantic Ocean by way of West Branch Brandywine Creek, Brandywine Creek, the Christina and the Delaware: about 65 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Unionville; river miles along the main stem, rounded.
Unionville has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 24° in January. A normal year brings about 12 inches of snow; with the rain, that comes to about 50 inches of water.
On November 14 Unionville normally reaches 53° and falls to 37°. The record high is 73°, in 1993; the record low 21°, in 1986. The most rain on this date, 2.17 in, fell in 1972.
Normals 1991–2020 and records since 1931 at Wilmington Porter Res, 13 miles southeast, 210 ft lower. NOAA, through RCC-ACIS.
