The South Lancaster 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.
3.64 inches of rain fell in two days, the most for this week of the year since records began in 1892. The next wettest, 2.98 inches, fell in 1947.
South Lancaster’s center stands about 290 ft above sea level. Within three miles the land runs from 220 ft to 620 ft, a difference of 400 ft: rolling country. The highest named summit within 15 miles is Wachusett Mountain, about 2,000 ft, 11 miles west-northwest.
Under the town center the state geologic map shows Littleton Formation (schist, phyllite), from the Early Devonian, 394 to 422 million years old.
The section below crosses 13 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 18×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Schist, phyllite. Age: Early Devonian, 394 to 422 million years old. About 6 mi of the line.
Schist, gneiss. Age: Neoproterozoic to Ordovician, 445 to 1,000 million years old. About 4 mi of the line.
Granofels, schist. Age: Neoproterozoic, 542 to 1,000 million years old. About 3 mi of the line.
Granite, pegmatite. Age: Ordovician to Silurian, 422 to 487 million years old. About 3 mi of the line.
Gneiss. Age: Early Devonian to Late Devonian, 375 to 405 million years old. About 2 mi of the line.
Granite. Age: Early Devonian to Late Devonian, 375 to 405 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. 7 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 South Lancaster reaches the Atlantic Ocean by way of Goodridge Brook, the Nashua and the Merrimack: about 95 river miles.
55 miles of the trip are on the Merrimack.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of South Lancaster; river miles along the main stem, rounded.
South Lancaster has a warm-summer humid continental climate. Summer afternoons average 80° in July; winter nights fall to about 17° in January. A normal year brings about 73 inches of snow; with the rain, that comes to about 48 inches of water.
On November 14 South Lancaster normally reaches 48° and falls to 33°. The record high is 68°, in 1989; the record low 10°, in 1986. The most rain on this date, 1.58 in, fell in 2009.
Normals 1991–2020 and records since 1892 from the Worcester Area threaded record (Worcester Regional Airport, 15 miles southwest, 710 ft higher). NOAA, through RCC-ACIS.