The Angwin 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 sunny
Showers likely
Showers likely
Showers likely
Showers likely
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Partly cloudy
80° on Nov. 15, 2010, the hottest reading for this week of the year since 1940. Next is 79° in 2008.
Angwin’s center stands about 1,760 ft above sea level. Within three miles the land runs from 340 ft to 2,360 ft, a difference of 2,020 ft: mountain country. The highest named summit within 15 miles is Mount Saint Helena, about 4,310 ft, 12 miles west-northwest.
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 8×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Rhyolite, dacite. Age: Late Miocene to Late Pliocene, 3 to 7 million years old. About 9 mi of the line.
Dacite. Age: Late Miocene to Late Pliocene, 3 to 7 million years old. About 7 mi of the line.
Sandstone, mudstone. Age: Jurassic to Cretaceous, 66 to 202 million years old. About 6 mi of the line.
Serpentinite. Age: Middle Jurassic to Late Jurassic, 145 to 175 million years old. About 2 mi of the line.
Siltstone-mudstone. Age: Early Cretaceous to Late Cretaceous, 66 to 145 million years old. About 0.6 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 Angwin reaches San Francisco Bay and the Pacific Ocean by way of Conn Creek and the Napa: about 45 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Angwin; river miles along the main stem, rounded.
Angwin has a warm-summer Mediterranean climate. Summer afternoons average 85° in July; winter nights fall to about 39° in January. About 40 inches of rain fall in a normal year.
On November 14 Angwin normally reaches 60° and falls to 43°. The record high is 79°, in 2008; the record low 28°, in 1985. The most rain on this date, 2.61 in, fell in 1981.
Normals 1991–2020 and records since 1940 at Angwin Pacific Union College, here. NOAA, through RCC-ACIS.
