The Topstone 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.
Mostly cloudy
Mostly sunny; warmer
Partly cloudy
Sunny
Mostly sunny
Mostly sunny
Mostly sunny
10° on Nov. 16, 1996, the coldest reading for this week of the year since 1937. Next is 14° in 1956.
Topstone’s center stands about 520 ft above sea level. Within three miles the land runs from 340 ft to 760 ft, a difference of 420 ft: hilly country. The highest named summit within 15 miles is Pond Mountain, about 1,200 ft, 15 miles north.
Under the town center the state geologic map shows Ordovician? granitic gneiss, from the Early Devonian to Middle Devonian, 393 to 419 million years old.
The section below crosses 8 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 21×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Gneiss. Age: Early Devonian to Middle Devonian, 393 to 419 million years old. About 9 mi of the line.
Gneiss, amphibolite. Age: Mesoproterozoic, 1 to 1.6 billion years old. About 5 mi of the line.
Gneiss. Age: Mesoproterozoic, 1 to 1.6 billion years old. About 5 mi of the line.
Schist, gneiss. Age: Early Ordovician to Middle Ordovician, 459 to 487 million years old. About 2 mi of the line.
Marble. Age: Cambrian to Early Ordovician, 471 to 542 million years old. About 2 mi of the line.
Gneiss. Age: Middle Ordovician, 459 to 471 million years old. About 0.9 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 2 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 Topstone reaches Long Island Sound and the Atlantic Ocean by way of the Norwalk: about 17 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Topstone; river miles along the main stem, rounded.
Topstone has a hot-summer humid continental climate. Summer afternoons average 85° in July; winter nights fall to about 21° in January. A normal year brings about 49 inches of snow; with the rain, that comes to about 53 inches of water.
On November 14 Topstone normally reaches 51° and falls to 34°. The record high is 73°, in 1993; the record low 16°, in 1939. The most rain on this date, 2.42 in, fell in 1937.
Normals 1991–2020 and records since 1937 at Danbury, 7 miles north, 120 ft lower. NOAA, through RCC-ACIS.
