The Sylvania 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.
73° on Nov. 11, 2020, the hottest reading for this week of the year since 1973. Next is 69° in 2012.
Sylvania’s center stands about 1,290 ft above sea level. Within three miles the land runs from 1,180 ft to 2,390 ft, a difference of 1,210 ft: steep hill country. The highest named summit within 15 miles is Armenia Mountain, about 2,460 ft, 4 miles south-southeast.
Under the town center the state geologic map shows Catskill Formation (sandstone, siltstone, shale), from the Late Devonian, 359 to 384 million years old.
The section below crosses 6 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 15×. 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, siltstone, shale. Age: Late Devonian, 359 to 384 million years old. About 9 mi of the line.
Sandstone, siltstone, mudstone. Age: Late Devonian, 359 to 384 million years old. About 6 mi of the line.
Sandstone, conglomerate. Age: Carboniferous, 299 to 324 million years old. About 4 mi of the line.
Sandstone, shale. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Sandstone. Age: Carboniferous, 324 to 359 million years old. About 1 mi of the line.
Sandstone, siltstone. Age: Devonian to Carboniferous, 324 to 422 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 Sylvania reaches Chesapeake Bay and the Atlantic Ocean by way of Spring Creek, Sugar Creek and the Susquehanna: about 310 river miles.
Lake on the way: Lake Aldred.
240 miles of the trip are on the Susquehanna.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Sylvania; river miles along the main stem, rounded.
Sylvania has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 15° in January. A normal year brings about 43 inches of snow; with the rain, that comes to about 36 inches of water.
Normals 1991–2020 and records since 1973 at Tioga Hammond Dam, 16 miles west-northwest. NOAA, through RCC-ACIS.