The Walthill 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
Mostly sunny; warmer
Mostly sunny
Partly cloudy
Partly cloudy
Mostly sunny
Showers likely
78° on Nov. 13, 1999, the hottest reading for this week of the year since 1889. Next is 77° in 1971.
Walthill’s center stands about 1,250 ft above sea level. Within three miles the land runs from 1,190 ft to 1,450 ft, a difference of 260 ft: rolling country.
Under the town center the state geologic map shows Dakota Group (sandstone, shale), from the Early Cretaceous, 100 to 145 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 40×. 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, 100 to 145 million years old. About 22 mi of the line.
Shale, limestone. Age: Late Cretaceous, 66 to 100 million years old. About 2 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 million years old. About 0.5 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 Walthill reaches the Gulf of America by way of South Omaha Creek, the Missouri and the Mississippi: about 1,900 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 Walthill; river miles along the main stem, rounded.
Walthill 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 Walthill 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, 18 miles north-northeast, 160 ft lower). NOAA, through RCC-ACIS.
