The Rockford 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.
Rockford’s center stands about 2,390 ft above sea level. Within three miles the land runs from 2,330 ft to 2,690 ft, a difference of 360 ft: rolling country. The highest named summit within 15 miles is Mica Peak, about 5,220 ft, 14 miles north-northeast.
Under the town center the state geologic map shows Alluvium (silt, sand), from the Holocene, less than 12,000 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 10×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Silt. Age: Pleistocene, less than 2.6 million years old. About 12 mi of the line.
Argillite, siltstone. Age: Mesoproterozoic to Early Cambrian, 521 to 1,600 million years old. About 7 mi of the line.
Silt, sand. Age: Holocene, less than 12,000 years old. About 4 mi of the line.
Age: Mesoproterozoic, 1 to 1.6 billion years old. About 1 mi of the line.
Basalt. Age: Late Oligocene to Early Pliocene, 3.6 to 28 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 Rockford reaches the Pacific Ocean by way of Mica Creek, Rock Creek, Hangman Creek, the Spokane and the Columbia: about 740 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 Rockford; river miles along the main stem, rounded.
Rockford 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 Rockford 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, 22 miles west-northwest). NOAA, through RCC-ACIS.