The Gilsum 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
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Mostly sunny
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0° on Nov. 16, 1933, the coldest reading for this week of the year since 1893. Next is 6° in 1905.
Gilsum’s center stands about 1,110 ft above sea level. Within three miles the land runs from 620 ft to 1,610 ft, a difference of 990 ft: steep hill country. The highest named summit within 15 miles is Monadnock Mountain, about 3,130 ft, 15 miles south-southeast.
The section below crosses 10 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 11×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Pelitic-schist, metasandstone. Age: Silurian, 434 to 445 million years old. About 6 mi of the line.
Metagraywacke. Age: Early Devonian, 410 to 414 million years old. About 4 mi of the line.
Metaclastic. Age: Silurian, 434 to 445 million years old. About 3 mi of the line.
Muscovite-schist, metagraywacke. Age: Silurian to Early Devonian, 394 to 425 million years old. About 3 mi of the line.
Granodiorite. Age: Early Devonian, 394 to 422 million years old. About 2 mi of the line.
Slate, schist. Age: Middle Ordovician to Late Ordovician, 445 to 471 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. 4 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 Gilsum reaches Long Island Sound and the Atlantic Ocean by way of White Brook, the Ashuelot and the Connecticut: about 180 river miles.
140 miles of the trip are on the Connecticut.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Gilsum; river miles along the main stem, rounded.
Gilsum has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 10° in January. A normal year brings about 60 inches of snow; with the rain, that comes to about 46 inches of water.
On November 14 Gilsum normally reaches 47° and falls to 27°. The record high is 68°, in 1989; the record low 6°, in 1905. The most rain on this date, 1.61 in, fell in 1937.
Normals 1991–2020 and records since 1893 at Keene, 8 miles south-southwest, 600 ft lower. NOAA, through RCC-ACIS.
