The Harlansburg 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.
78° on Nov. 12, 2010, the hottest reading for this week of the year since 1949. Next is 75° in 2009.
Harlansburg’s center stands about 1,150 ft above sea level. Within three miles the land runs from 1,090 ft to 1,370 ft, a difference of 280 ft: rolling country. The highest named summit within 15 miles is Turkey Hill, about 1,370 ft, 10 miles southwest.
Under the town center the state geologic map shows Pottsville Formation (sandstone, conglomerate), from the Carboniferous, 299 to 324 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 24×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone. Age: Carboniferous, 299 to 324 million years old. About 12 mi of the line.
Sandstone, conglomerate. Age: Carboniferous, 299 to 324 million years old. About 6 mi of the line.
Shale. Age: Carboniferous, 299 to 324 million years old. About 4 mi of the line.
Sandstone. Age: Carboniferous, 324 to 359 million years old. About 1 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
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 Harlansburg reaches the Gulf of America by way of Slippery Rock Creek, Connoquenessing Creek, the Beaver, the Ohio and the Mississippi: about 1,950 river miles.
970 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Harlansburg; river miles along the main stem, rounded.
Harlansburg has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 17° in January. About 45 inches of rain fall in a normal year.
On November 14 Harlansburg normally reaches 50° and falls to 31°. The record high is 75°, in 2009; the record low 8°, in 1986. The most rain on this date, 1.15 in, fell in 1972.
Normals 1991–2020 and records since 1949 at Slippery Rock 1 SSW, 7 miles east-northeast, 110 ft higher. NOAA, through RCC-ACIS.