The Tiawah 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.
87° on Nov. 15, 2025, the hottest reading for this week of the year since 1893. Next is 85° in 1911.
Tiawah’s center stands about 620 ft above sea level. Within three miles the land runs from 550 ft to 780 ft, a difference of 230 ft: rolling country. The highest named summit within 15 miles is Indian Hills, about 870 ft, 13 miles west-southwest.
Under the town center the state geologic map shows Boggy Formation (shale, sandstone), from the Carboniferous, 299 to 324 million years old.
The section below crosses 5 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 51×. 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: Carboniferous, 299 to 324 million years old. About 10 mi of the line.
Sandstone, shale. Age: Carboniferous, 299 to 324 million years old. About 6 mi of the line.
Fine-detrital. Age: Holocene, less than 12,000 years old. About 4 mi of the line.
Shale. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Shale. Age: Carboniferous, 299 to 324 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 Tiawah reaches the Gulf of America by way of Otter Creek, Dog Creek, the Verdigris, the Arkansas and the Mississippi: about 1,050 river miles.
Lakes on the way: Murray Lake and Ozark Lake.
600 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Tiawah; river miles along the main stem, rounded.
Tiawah has a humid subtropical climate. Summer afternoons average 94° in July; winter nights fall to about 28° in January. A normal year brings about 9 inches of snow; with the rain, that comes to about 41 inches of water.
On November 14 Tiawah normally reaches 62° and falls to 40°. The record high is 79°, in 2020; the record low 13°, in 1916. The most rain on this date, 1.72 in, fell in 1909.
Normals 1991–2020 and records since 1893 from the Tulsa Area threaded record (Tulsa International Airport, 18 miles west-southwest). NOAA, through RCC-ACIS.