The Tonasket 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.
63° on Nov. 15, 2021, the hottest reading for this week of the year since 1909. Next is 62° in 1990.
Tonasket’s center stands about 910 ft above sea level. Within three miles the land runs from 880 ft to 2,300 ft, a difference of 1,420 ft: steep hill country. The highest named summit within 15 miles is Tunk Mountain, about 6,020 ft, 15 miles southeast.
Under the town center the state geologic map shows Glacial drift, undivided (sand, gravel), from the Pleistocene, less than 2.6 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 4×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sand, gravel. Age: Pleistocene, less than 2.6 million years old. About 8 mi of the line.
Metasedimentary. Age: Permian, 252 to 299 million years old. About 8 mi of the line.
Granite. Age: Precambrian to Eocene. About 7 mi of the line.
Andesite, dacite. Age: Eocene to Oligocene, 23 to 56 million years old. About 0.5 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 Tonasket reaches the Pacific Ocean by way of the Okanogan and the Columbia: about 580 river miles.
Lake on the way: Lake Umatilla.
250 miles of the trip are on the Columbia.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Tonasket; river miles along the main stem, rounded.
Tonasket has a cold semi-arid climate. Summer afternoons average 89° in July; winter nights fall to about 23° in January. About 12 inches of rain fall in a normal year.
On November 14 Tonasket normally reaches 44° and falls to 29°. The record high is 59°, in 2016; the record low 3°, in 1955. The most rain on this date, 0.61 in, fell in 1963.
Normals 1991–2020 and records since 1909 from the Omak Area threaded record (Omak, 17 miles south-southwest, 390 ft higher). NOAA, through RCC-ACIS.