The South Dennis 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.
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77° on Nov. 12, 2022, the hottest reading for this week of the year since 1893. Next is 70° in 1909.
South Dennis’s center stands about 40 ft above sea level. Within three miles the land runs from 0 ft to 110 ft, a difference of 110 ft: gently rolling country. Open water lies within three miles. The highest named summit within 15 miles is Clay Hill, about 210 ft, 10 miles west.
Under the town center the state geologic map shows Granite, gneiss, and schist, undivided (granite, gneiss, schist), from the Neoproterozoic, 542 to 1,000 million years old.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Granite, gneiss, schist. Age: Neoproterozoic, 542 to 1,000 million years old. About 17 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 South Dennis reaches the Atlantic Ocean by way of the Swan Pond: about 2 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of South Dennis; river miles along the main stem, rounded.
South Dennis has a warm-summer humid continental climate. Summer afternoons average 78° in July; winter nights fall to about 22° in January. A normal year brings about 22 inches of snow; with the rain, that comes to about 46 inches of water.
On November 14 South Dennis normally reaches 52° and falls to 37°. The record high is 67°, in 1941; the record low 18°, in 1986. The most rain on this date, 1.07 in, fell in 1940.
Normals 1991–2020 and records since 1893 at Hyannis, 8 miles west-southwest. NOAA, through RCC-ACIS.
