The Green Bluff 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.
67° on Nov. 12, 1999, the hottest reading for this week of the year since 1881. Next is 65° in 1899.
Green Bluff’s center stands about 2,310 ft above sea level. Within three miles the land runs from 1,850 ft to 2,400 ft, a difference of 550 ft: hilly country. The highest named summit within 15 miles is Mount Spokane, about 5,870 ft, 10 miles northeast.
Under the town center the state geologic map shows Miocene volcanic rocks (basalt), from the Late Oligocene to Early Pliocene, 3.6 to 28 million years old.
The section below crosses 6 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.
Fine-detrital, coarse-detrital. Age: Late Pliocene to Pleistocene, less than 3.6 million years old. About 10 mi of the line.
Granite. Age: Precambrian to Eocene. About 8 mi of the line.
Basalt. Age: Late Oligocene to Early Pliocene, 3.6 to 28 million years old. About 3 mi of the line.
Argillite, siltstone. Age: Mesoproterozoic to Early Cambrian, 521 to 1,600 million years old. About 2 mi of the line.
Sand, gravel. Age: Pleistocene, less than 2.6 million years old. About 1 mi of the line.
Siltstone, sandstone. Age: Middle Miocene to Early Pliocene, 3.6 to 16 million years old. About 0.3 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 Green Bluff reaches the Pacific Ocean by way of Deadman Creek, the Little Spokane, the Spokane and the Columbia: about 710 river miles.
Lake on the way: Lake Umatilla.
360 miles of the trip are on the Columbia.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Green Bluff; river miles along the main stem, rounded.
Green Bluff has a dry-summer warm-summer continental climate. Summer afternoons average 84° in July; winter nights fall to about 24° in December. A normal year brings about 45 inches of snow; with the rain, that comes to about 16 inches of water.
On November 14 Green Bluff normally reaches 43° and falls to 31°. The record high is 65°, in 1899; the record low −7°, in 1955. The most rain on this date, 0.74 in, fell in 1966.
Normals 1991–2020 and records since 1881 from the Spokane Area threaded record (Spokane International Airport, 19 miles southwest). NOAA, through RCC-ACIS.