The Des Moines 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.
3.80 inches of rain fell in two days, the most for this week of the year since records began in 1945. The next wettest, 3.18 inches, fell in 2015.
Des Moines’s center stands about 80 ft above sea level. Within three miles the land runs from 10 ft to 450 ft, a difference of 440 ft: hilly country. Open water lies within three miles. The highest named summit within 15 miles is Squak Mountain, about 2,040 ft, 15 miles east-northeast.
Under the town center the state geologic map shows Older glacial drift (fine-detrital, coarse-detrital), from the Late Pliocene to Pleistocene, less than 3.6 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 19×. 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, sand. Age: Holocene, less than 12,000 years old. About 5 mi of the line.
Fine-detrital, coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 4 mi of the line.
Fine-detrital, coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 2 mi of the line.
Fine-detrital, coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 1 mi of the line.
Fine-detrital, coarse-detrital. Age: Late Pliocene to Pleistocene, less than 3.6 million years old. About 0.4 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.
Rain that falls on Des Moines runs straight into Puget Sound and the Pacific Ocean.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Des Moines; river miles along the main stem, rounded.
Des Moines has a warm-summer Mediterranean climate. Summer afternoons average 78° in August; winter nights fall to about 37° in December. A normal year brings about 6 inches of snow; with the rain, that comes to about 39 inches of water.
On November 14 Des Moines normally reaches 52° and falls to 41°. The record high is 65°, in 1995; the record low 9°, in 1955. The most rain on this date, 2.61 in, fell in 2001.
Normals 1991–2020 and records since 1945 from the Seattle Tacoma Area threaded record (Seattle Tacoma Airport, 3 miles north, 290 ft higher). NOAA, through RCC-ACIS.