The Nezperce 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.
68° on Nov. 12, 1999, the hottest reading for this week of the year since 1950. Next is 68° in 2016.
Nezperce’s center stands about 3,210 ft above sea level. Within three miles the land runs from 3,040 ft to 3,470 ft, a difference of 430 ft: hilly country. The highest named summit within 15 miles is Big Butte, about 3,880 ft, 8 miles southeast.
Under the town center the state geologic map shows Columbia River Basalt Group (basalt, basaltic-andesite), from the Early Miocene to Late Miocene, 6 to 18 million years old.
The section below crosses 5 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 6×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Basalt, basaltic-andesite. Age: Early Miocene to Late Miocene, 6 to 18 million years old. About 16 mi of the line.
Quartz-diorite. Age: Late Jurassic to Late Cretaceous, 90 to 160 million years old. About 7 mi of the line.
Granodiorite, tonalite, quartz-diorite. Age: Late Jurassic to Late Cretaceous, 87 to 160 million years old. About 1 mi of the line.
Schist, gneiss, amphibolite. Age: Permian to Cretaceous, 66 to 299 million years old. About 0.5 mi of the line.
Basalt, rhyolite. Age: Permian to Triassic, 202 to 299 million years old. About 0.4 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 Nezperce reaches the Pacific Ocean by way of Long Hollow Creek, Little Canyon Creek, Big Canyon Creek, the Clearwater, the Snake and the Columbia: about 520 river miles.
Lake on the way: Lake Umatilla.
210 miles of the trip are on the Columbia.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Nezperce; river miles along the main stem, rounded.
Nezperce has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 24° in December. A normal year brings about 61 inches of snow; with the rain, that comes to about 23 inches of water.
On November 14 Nezperce normally reaches 44° and falls to 30°. The record high is 64°, in 1999; the record low 12°, in 1985. The most rain on this date, 0.38 in, fell in 1988.
Normals 1991–2020 and records since 1950 at Cottonwood 2 WSW, 16 miles south-southwest, 740 ft higher. NOAA, through RCC-ACIS.