The Walnut Hill 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.
81° on Nov. 14, 1993, the hottest reading for this week of the year since 1937. Next is 78° in 1945.
Walnut Hill’s center stands about 1,620 ft above sea level. Within three miles the land runs from 1,470 ft to 2,120 ft, a difference of 650 ft: hilly country. The highest named summit within 15 miles is Holston Mountain, about 4,170 ft, 13 miles southeast.
Under the town center the state geologic map shows Knox Group, including Jonesboro Limestone, Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, Chepultepec Dolomite, Copper Ridge Dolomite, Conococheague Limestone (limestone, dolostone), from the Cambrian to Ordovician, 445 to 542 million years old.
The section below crosses 16 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 7×. 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. Age: Ordovician, 445 to 487 million years old. About 6 mi of the line.
Limestone, dolostone. Age: Cambrian to Ordovician, 445 to 542 million years old. About 6 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 2 mi of the line.
Shale, sandstone, mudstone. Age: Carboniferous, 324 to 359 million years old. About 1 mi of the line.
Dolostone, limestone. Age: Cambrian to Ordovician, 445 to 542 million years old. About 1 mi of the line.
Dolostone. Age: Cambrian, 487 to 542 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. 10 smaller units along the line are not listed.
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 Walnut Hill reaches the Gulf of America by way of Back Creek, Beaver Creek, the South Fork Holston, the Holston, the Tennessee, the Ohio and the Mississippi: about 1,830 river miles.
Lakes on the way: Guntersville Lake, White Lake (historical), Pickwick Lake and Cummings Lake.
970 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Walnut Hill; river miles along the main stem, rounded.
Walnut Hill has a humid subtropical climate. Summer afternoons average 86° in July; winter nights fall to about 26° in January. A normal year brings about 9 inches of snow; with the rain, that comes to about 44 inches of water.
On November 14 Walnut Hill normally reaches 59° and falls to 34°. The record high is 81°, in 1993; the record low 16°, in 1986. The most rain on this date, 0.62 in, fell in 1945.
Normals 1991–2020 and records since 1937 from the Bristol-Johnson City Area threaded record (Bristol Airport, 10 miles southwest, 120 ft lower). NOAA, through RCC-ACIS.