The Salix 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.
78° on Nov. 13, 1999, the hottest reading for this week of the year since 1889. Next is 77° in 1971.
Salix’s center stands about 1,080 ft above sea level. Within three miles the land runs from 1,060 ft to 1,090 ft, a difference of 30 ft: nearly flat ground.
Under the town center the state geologic map shows Gilmore City Formation (limestone), from the Early Mississippian to Middle Mississippian, 331 to 359 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 45×. 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, shale. Age: Early Cretaceous to Late Cretaceous, 94 to 113 million years old. About 11 mi of the line.
Limestone. Age: Early Mississippian to Middle Mississippian, 331 to 359 million years old. About 5 mi of the line.
Sandstone, shale. Age: Early Cretaceous, 100 to 145 million years old. About 4 mi of the line.
Shale, limestone. Age: Late Cretaceous, 66 to 100 million years old. About 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.
Salix has a hot-summer humid continental climate. Summer afternoons average 85° in July; winter nights fall to about 10° in January. A normal year brings about 36 inches of snow; with the rain, that comes to about 29 inches of water.
On November 14 Salix normally reaches 48° and falls to 26°. The record high is 76°, in 2025; the record low −9°, in 1959. The most rain on this date, 1.08 in, fell in 1926.
Normals 1991–2020 and records since 1889 from the Sioux City Area threaded record (Sioux City Airport, 7 miles northwest). NOAA, through RCC-ACIS.