The Lake Bosworth 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.
Showers likely
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26° on Nov. 15, 2014, the coldest reading for this week of the year since 1948. Next is 27° in 2000.
Lake Bosworth’s center stands about 660 ft above sea level. Within three miles the land runs from 220 ft to 980 ft, a difference of 760 ft: hilly country. The highest named summit within 15 miles is Liberty Mountain, about 5,600 ft, 15 miles east-northeast.
Under the town center the state geologic map shows Younger glacial drift (fine-detrital, coarse-detrital), from the Pleistocene, less than 2.6 million years old.
The section below crosses 8 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 5×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Fine-detrital, coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 8 mi of the line.
Silt, sand. Age: Holocene, less than 12,000 years old. About 4 mi of the line.
Argillite, graywacke. Age: Late Jurassic to Early Cretaceous, 100 to 164 million years old. About 4 mi of the line.
Fine-detrital, coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 4 mi of the line.
Granite, granodiorite, trondhjemite. Age: Late Cretaceous to Eocene, 34 to 100 million years old. About 2 mi of the line.
Conglomerate. Age: Late Eocene to Early Miocene, 16 to 38 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. 2 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 Lake Bosworth reaches Puget Sound and the Pacific Ocean by way of the Pilchuck and the Snohomish: about 30 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Lake Bosworth; river miles along the main stem, rounded.
Lake Bosworth has a warm-summer Mediterranean climate. Summer afternoons average 73° in August; winter nights fall to about 36° in December. About 33 inches of rain fall in a normal year.
On November 14 Lake Bosworth normally reaches 50° and falls to 40°. The record high is 60°, in 2021; the record low 28°, in 2014. The most rain on this date, 1.51 in, fell in 2015.
Normals 1991–2020 and records since 1948 at Everett Snohomish County Airport, 17 miles west-southwest, 110 ft lower. NOAA, through RCC-ACIS.
