The Arcata 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.
Chance of showers
Showers likely
Showers likely
Showers likely
Showers likely
Chance of showers
Partly cloudy
3.75 inches of rain fell in two days, the most for this week of the year since records began in 1886. The next wettest, 3.59 inches, fell in 1900.
Arcata’s center stands about 20 ft above sea level. Within three miles the land runs from 0 ft to 1,190 ft, a difference of 1,190 ft: steep hill country. Open water lies within three miles. The highest named summit within 15 miles is Bald Mountain, about 3,170 ft, 11 miles east.
Under the town center the state geologic map shows Quaternary alluvium and marine deposits (coarse-detrital), from the Pleistocene to Holocene, 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 7×. 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, mudstone. Age: Jurassic to Cretaceous, 66 to 202 million years old. About 8 mi of the line.
Coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 4 mi of the line.
Coarse-detrital. Age: Pleistocene to Holocene, less than 2.6 million years old. About 3 mi of the line.
Mica-schist. Age: Early Cretaceous, 110 to 143 million years old. About 0.5 mi of the line.
Sand. Age: Quaternary, less than 2.6 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 Arcata reaches the Pacific Ocean by way of Gannon Slough and Jacoby Creek: about 1 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Arcata; river miles along the main stem, rounded.
Arcata has a warm-summer Mediterranean climate. Summer afternoons average 64° in August; winter nights fall to about 40° in December. About 40 inches of rain fall in a normal year.
On November 14 Arcata normally reaches 58° and falls to 44°. The record high is 71°, in 1970; the record low 31°, in 1978. The most rain on this date, 2.42 in, fell in 1934.
Normals 1991–2020 and records since 1886 from the Eureka Area threaded record (Eureka Wfo Woodley Island, 6 miles southwest). NOAA, through RCC-ACIS.
