The Terrebonne 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 cloudy
Mostly cloudy
Partly cloudy
Chance of showers
Chance of showers
Mostly cloudy
Partly cloudy
−19° on Nov. 16, 2014, the coldest reading for this week of the year since 1948. Next is −14° in 1955.
Terrebonne’s center stands about 2,880 ft above sea level. Within three miles the land runs from 2,640 ft to 3,080 ft, a difference of 440 ft: hilly country. The highest named summit within 15 miles is Grizzly Mountain, about 5,630 ft, 13 miles east-northeast.
The section below crosses 9 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 11×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, siltstone, mudstone. Age: Miocene to Pliocene, 2.6 to 23 million years old. About 7 mi of the line.
Basalt. Age: Miocene to Pliocene, 2.6 to 23 million years old. About 4 mi of the line.
Hypabyssal-rhyolite, hypabyssal-dacite. Age: Miocene, 5.3 to 23 million years old. About 3 mi of the line.
Age: Pliocene to Pleistocene, less than 5.3 million years old. About 3 mi of the line.
Andesite. Age: Paleocene to Early Oligocene, 28 to 66 million years old. About 2 mi of the line.
Rhyolite, dacite. Age: Miocene to Pliocene, 2.6 to 23 million years old. About 2 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 3 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 Terrebonne reaches the Pacific Ocean by way of the Crooked River, the Deschutes and the Columbia: about 330 river miles.
Lake on the way: Lake Billy Chinook.
200 miles of the trip are on the Columbia.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Terrebonne; river miles along the main stem, rounded.
Terrebonne has a cold semi-arid climate. Summer afternoons average 87° in July; winter nights fall to about 23° in December. About 8 inches of rain fall in a normal year.
On November 14 Terrebonne normally reaches 51° and falls to 28°. The record high is 74°, in 1999; the record low −7°, in 1955. The most rain on this date, 0.67 in, fell in 2014.
Normals 1991–2020 and records since 1948 at Redmond Airport, 7 miles south-southeast, 170 ft higher. NOAA, through RCC-ACIS.
