The Coronita 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.
23° on Nov. 11, 1950, the coldest reading for this week of the year since 1893. Next is 25° in 1958.
Coronita’s center stands about 670 ft above sea level. Within three miles the land runs from 460 ft to 2,690 ft, a difference of 2,230 ft: mountain country. The highest named summit within 15 miles is Santiago Peak, about 5,660 ft, 12 miles south-southeast.
Under the town center the state geologic map shows Older Quaternary alluvium and marine deposits (coarse-detrital), from the Pleistocene, less than 2.6 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 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.
Coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 8 mi of the line.
Coarse-detrital. Age: Pleistocene to Holocene, less than 2.6 million years old. About 7 mi of the line.
Argillite. Age: Paleozoic to Late Jurassic, 145 to 542 million years old. About 6 mi of the line.
Felsic-volcanic, mafic-volcanic. Age: Late Jurassic to Early Cretaceous, 100 to 164 million years old. About 2 mi of the line.
Sandstone, mudstone. Age: Paleocene, 56 to 66 million years old. About 1 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.
Coronita has a hot semi-arid climate. Summer afternoons average 95° in August; winter nights fall to about 43° in December. About 9 inches of rain fall in a normal year.
On November 14 Coronita normally reaches 75° and falls to 48°. The record high is 95°, in 1906; the record low 27°, in 1915. The most rain on this date, 0.54 in, fell in 1972.
Normals 1991–2020 and records since 1893 from the Riverside Area threaded record (Riverside Municipal Airport, 11 miles east-northeast, 180 ft higher). NOAA, through RCC-ACIS.