The Bryn Athyn 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
Mostly sunny; warmer
Partly cloudy
Mostly sunny
Sunny
Mostly sunny
Mostly sunny
81° on Nov. 15, 1993, the hottest reading for this week of the year since 1945. Next is 77° in 2006.
Bryn Athyn’s center stands about 210 ft above sea level. Within three miles the land runs from 110 ft to 390 ft, a difference of 280 ft: rolling country. The highest named summit within 15 miles is Buckingham Mountain, about 570 ft, 13 miles north.
The section below crosses 11 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 38×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Arkose. Age: Triassic, 202 to 252 million years old. About 6 mi of the line.
Mica-schist. Age: Paleozoic, 252 to 542 million years old. About 4 mi of the line.
Argillite. Age: Triassic, 202 to 252 million years old. About 4 mi of the line.
Sand, clay. Age: Late Cretaceous, 94 to 100 million years old. About 3 mi of the line.
Gneiss. Age: Precambrian. About 2 mi of the line.
Sand. Age: Miocene, 5.3 to 23 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. 5 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 Bryn Athyn reaches Delaware Bay and the Atlantic Ocean by way of Pennypack Creek and the Delaware: about 90 river miles.
75 miles of the trip are on the Delaware.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Bryn Athyn; river miles along the main stem, rounded.
Bryn Athyn has a humid subtropical climate. Summer afternoons average 88° in July; winter nights fall to about 27° in January. About 45 inches of rain fall in a normal year.
On November 14 Bryn Athyn normally reaches 57° and falls to 39°. The record high is 74°, in 1993; the record low 20°, in 1986. The most rain on this date, 2.30 in, fell in 1972.
Normals 1991–2020 and records since 1945 at Northeast Philadelphia Airport, 5 miles southeast, 100 ft lower. NOAA, through RCC-ACIS.
