The Portage Des Sioux 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.
Sunny
Partly cloudy; warmer
Sunny
Sunny
Partly cloudy
Partly cloudy
Partly cloudy
85° on Nov. 11, 1989, the hottest reading for this week of the year since 1874. Next is 83° in 2016.
Portage Des Sioux’s center stands about 420 ft above sea level. Within three miles the land runs from 410 ft to 710 ft, a difference of 300 ft: rolling country. The highest named summit within 15 miles is Tucker Knob, about 890 ft, 10 miles west-northwest.
Under the town center the state geologic map shows Holocene series (clay, silt, sand), from the Holocene, less than 12,000 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 43×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Clay, silt, sand. Age: Holocene, less than 12,000 years old. About 18 mi of the line.
Shale, limestone. Age: Late Ordovician, 445 to 454 million years old. About 3 mi of the line.
Limestone, shale. Age: Early Mississippian, 347 to 359 million years old. About 2 mi of the line.
Limestone. Age: Middle Mississippian, 331 to 347 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.
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 Portage Des Sioux reaches the Gulf of America by way of the Mississippi: about 1,180 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Portage Des Sioux; river miles along the main stem, rounded.
Portage Des Sioux has a hot-summer humid continental climate. Summer afternoons average 90° in July; winter nights fall to about 24° in January. A normal year brings about 17 inches of snow; with the rain, that comes to about 42 inches of water.
On November 14 Portage Des Sioux normally reaches 56° and falls to 38°. The record high is 81°, in 1971; the record low 13°, in 1940. The most rain on this date, 1.86 in, fell in 1993.
Normals 1991–2020 and records since 1874 from the St Louis Area threaded record (St Louis Lambert International Airport, 12 miles south, 110 ft higher). NOAA, through RCC-ACIS.
