The Port Byron 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
Mostly sunny; warmer
Mostly sunny
Mostly sunny
Partly cloudy
Mostly sunny
Chance of showers
73° on Nov. 11, 1964, the hottest reading for this week of the year since 1938. Next is 73° in 1989.
Port Byron’s center stands about 610 ft above sea level. Within three miles the land runs from 560 ft to 740 ft, a difference of 180 ft: gently rolling country.
Under the town center the state geologic map shows Silurian System undivided (dolostone, limestone), from the Silurian, 422 to 445 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.
Dolostone, limestone. Age: Silurian, 422 to 445 million years old. About 12 mi of the line.
Dolostone, mudstone. Age: Silurian, 425 to 434 million years old. About 8 mi of the line.
Shale, sandstone, siltstone. Age: Early Pennsylvanian to Middle Pennsylvanian, 307 to 324 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 Port Byron reaches the Gulf of America by way of the Mississippi: about 1,470 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Port Byron; river miles along the main stem, rounded.
Port Byron has a hot-summer humid continental climate. Summer afternoons average 85° in July; winter nights fall to about 14° in January. About 37 inches of rain fall in a normal year.
On November 14 Port Byron normally reaches 49° and falls to 32°. The record high is 72°, in 1971; the record low 10°, in 1959. The most rain on this date, 0.60 in, fell in 1972.
Normals 1991–2020 and records since 1938 at Le Claire L&D 14, 4 miles west-southwest. NOAA, through RCC-ACIS.
