The Essex 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.
75° on Nov. 11, 2022, the hottest reading for this week of the year since 1990. Next is 74° in 1999.
Essex’s center stands about 590 ft above sea level. Within three miles the land runs from 570 ft to 630 ft, a difference of 60 ft: nearly flat ground. The highest named summit within 15 miles is Pilot Hill, about 780 ft, 13 miles southeast.
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 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.
Shale, sandstone. Age: Early Pennsylvanian to Middle Pennsylvanian, 307 to 324 million years old. About 12 mi of the line.
Shale, limestone. Age: Late Ordovician, 445 to 454 million years old. About 8 mi of the line.
Shale, sandstone, coal. Age: Middle Pennsylvanian to Late Pennsylvanian, 304 to 315 million years old. About 3 mi of the line.
Dolostone, limestone. Age: Silurian, 422 to 445 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 Essex reaches the Gulf of America by way of the Mazon, the Illinois and the Mississippi: about 1,490 river miles.
Lake on the way: Peoria Lake.
1,190 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Essex; river miles along the main stem, rounded.
Essex has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 14° in January. A normal year brings about 23 inches of snow; with the rain, that comes to about 38 inches of water.
On November 14 Essex normally reaches 49° and falls to 30°. The record high is 74°, in 1999; the record low 8°, in 1996. The most rain on this date, 0.80 in, fell in 1991.
Normals 1991–2020 and records since 1990 at Dwight Wwtp, 13 miles west-southwest. NOAA, through RCC-ACIS.