The Sprague 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
Mostly sunny; warmer
Partly cloudy
Mostly sunny
Mostly sunny
Mostly sunny
Mostly sunny
12° on Nov. 16, 1996, the coldest reading for this week of the year since 1956. Next is 14° in 1956.
Sprague’s center stands about 360 ft above sea level. Within three miles the land runs from 90 ft to 540 ft, a difference of 450 ft: hilly country. The highest named summit within 15 miles is Sunset Hill, about 850 ft, 11 miles north.
Under the town center the state geologic map shows Fly Pond (calc-silicate) Member [of Tatnic Hill Formation] (calc-silicate-gneiss), from the Neoproterozoic, 542 to 1,000 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 23×. 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, schist. Age: Neoproterozoic, 542 to 1,000 million years old. About 7 mi of the line.
Schist. Age: Silurian to Devonian, 359 to 445 million years old. About 6 mi of the line.
Schist, calc-silicate-rock. Age: Neoproterozoic, 542 to 1,000 million years old. About 3 mi of the line.
Calc-silicate-gneiss. Age: Neoproterozoic, 542 to 1,000 million years old. About 3 mi of the line.
Schist. Age: Neoproterozoic, 542 to 1,000 million years old. About 2 mi of the line.
Gneiss. Age: Neoproterozoic, 542 to 1,000 million years old. About 1 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 Sprague reaches Long Island Sound and the Atlantic Ocean by way of the Little River, the Shetucket and the Thames: about 25 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Sprague; river miles along the main stem, rounded.
Sprague has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 21° in January. A normal year brings about 28 inches of snow; with the rain, that comes to about 52 inches of water.
On November 14 Sprague normally reaches 54° and falls to 35°. The record high is 72°, in 1993; the record low 17°, in 1986. The most rain on this date, 2.25 in, fell in 1972.
Normals 1991–2020 and records since 1956 at Norwich Public Utility Plant, 8 miles south, 340 ft lower. NOAA, through RCC-ACIS.
