The Silverton 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.
Mostly sunny
Mostly sunny; warmer
Partly cloudy
Mostly cloudy
Chance of showers
Mostly cloudy; cooler
Chance of showers
63° on Nov. 16, 2001, the hottest reading for this week of the year since 1957. Next is 62° in 2025.
Silverton’s center stands about 1,140 ft above sea level. Within three miles the land runs from 1,130 ft to 1,160 ft, a difference of 30 ft: nearly flat ground.
Under the town center the state geologic map shows Mafic metavolcanic rocks (metabasalt, greenstone), from the Neoarchean, 2.5 to 2.8 billion years old.
The section below crosses 3 rock units mapped at the surface.
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.
Granodiorite, diorite. Age: Neoarchean, 2.5 to 2.8 billion years old. About 11 mi of the line.
Metabasalt, greenstone. Age: Neoarchean, 2.5 to 2.8 billion years old. About 8 mi of the line.
Gabbro, peridotite, pyroxenite. Age: Neoarchean, 2.5 to 2.8 billion years old. About 5 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 Silverton reaches Hudson Bay by way of the Red Lake, the Red River of the North and the Nelson: about 1,080 river miles. Past the border it runs north through Canada to Hudson Bay.
Lake on the way: Lake Winnipeg.
400 miles of the trip are on the Nelson.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Silverton; river miles along the main stem, rounded.
Silverton has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about −3° in January. About 24 inches of rain fall in a normal year.
On November 14 Silverton normally reaches 36° and falls to 20°. The record high is 62°, in 2025; the record low −4°, in 1959. The most rain on this date, 0.35 in, fell in 1994.
Normals 1991–2020 and records since 1957 at Agassiz Refuge, 12 miles north-northeast. NOAA, through RCC-ACIS.
