The Prosser 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.
Partly cloudy
Mostly sunny; warmer
Mostly sunny
Partly cloudy
Mostly sunny; warmer
Partly cloudy
Showers likely
83° on Nov. 14, 2025, the hottest reading for this week of the year since 1894. Next is 81° in 1999.
Prosser’s center stands about 2,050 ft above sea level. Within three miles the land runs from 1,970 ft to 2,060 ft, a difference of 90 ft: gently rolling country.
Under the town center the state geologic map shows Ogallala Group or Formation (siltstone-mudstone, conglomerate-sandstone), from the Miocene, 5.3 to 23 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Siltstone-mudstone, conglomerate-sandstone. Age: Miocene, 5.3 to 23 million years old. About 12 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 million years old. About 9 mi of the line.
Limestone, shale. Age: Late Cretaceous, 66 to 100 million years old. About 3 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 Prosser reaches the Gulf of America by way of the Platte, the Missouri and the Mississippi: about 1,950 river miles.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Prosser; river miles along the main stem, rounded.
Prosser has a hot-summer humid continental climate. Summer afternoons average 88° in July; winter nights fall to about 16° in January. About 26 inches of rain fall in a normal year.
On November 14 Prosser normally reaches 52° and falls to 29°. The record high is 83°, in 2025; the record low −7°, in 1940. The most rain on this date, 1.20 in, fell in 1926.
Normals 1991–2020 and records since 1894 from the Hastings Area threaded record (Hastings Municipal Airport, 10 miles southeast, 110 ft lower). NOAA, through RCC-ACIS.
