The Walpole 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.
75° on Nov. 15, 1993, the hottest reading for this week of the year since 1972. Next is 74° in 2020.
Walpole’s center stands about 150 ft above sea level. Within three miles the land runs from 110 ft to 470 ft, a difference of 360 ft: rolling country. The highest named summit within 15 miles is Great Blue Hill, about 630 ft, 9 miles east-northeast.
Under the town center the state geologic map shows Wamsutta Formation (conglomerate, graywacke), from the Carboniferous, 299 to 324 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 45×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Conglomerate, graywacke. Age: Carboniferous, 299 to 324 million years old. About 10 mi of the line.
Granite. Age: Neoproterozoic, 615 to 645 million years old. About 4 mi of the line.
Rhyolite. Age: Neoproterozoic, 599 to 605 million years old. About 3 mi of the line.
Granite. Age: Neoproterozoic, 542 to 1,000 million years old. About 3 mi of the line.
Rhyolite, mafic-volcanic. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Conglomerate, sandstone, siltstone. Age: Neoproterozoic to Early Cambrian, 521 to 1,000 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.
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 Walpole reaches Boston Harbor and the Atlantic Ocean by way of the Neponset: about 20 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Walpole; river miles along the main stem, rounded.
Walpole has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 20° in January. A normal year brings about 56 inches of snow; with the rain, that comes to about 50 inches of water.
On November 14 Walpole normally reaches 52° and falls to 34°. The record high is 71°, in 1993; the record low 12°, in 1986. The most rain on this date, 0.96 in, fell in 1988.
Normals 1991–2020 and records since 1972 at Walpole 2, here. NOAA, through RCC-ACIS.