The Grand Ridge 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 cloudy
Mostly sunny; warmer
Mostly sunny
Mostly sunny
Mostly sunny
28° on Nov. 12, 2011, the coldest reading for this week of the year since 1950. Next is 28° in 2019.
Grand Ridge’s center stands about 160 ft above sea level. Within three miles the land runs from 110 ft to 240 ft, a difference of 130 ft: gently rolling country.
Under the town center the state geologic map shows Residuum on Miocene sediments (clay), from the Late Miocene, 5.3 to 12 million years old.
The section below crosses 6 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.
Clay. Age: Oligocene, 23 to 34 million years old. About 7 mi of the line.
Clay. Age: Late Miocene, 5.3 to 12 million years old. About 6 mi of the line.
Sand. Age: Late Pliocene, 2.6 to 3.6 million years old. About 4 mi of the line.
Dolostone. Age: Early Miocene, 16 to 23 million years old. About 3 mi of the line.
Limestone. Age: Oligocene, 23 to 34 million years old. About 2 mi of the line.
Limestone. Age: Oligocene, 23 to 34 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.
Grand Ridge has a humid subtropical climate. Summer afternoons average 92° in July; winter nights fall to about 41° in January. About 51 inches of rain fall in a normal year.
On November 14 Grand Ridge normally reaches 72° and falls to 47°. The record high is 85°, in 1955; the record low 29°, in 2013. The most rain on this date, 1.83 in, fell in 1957.
Normals 1991–2020 and records since 1950 at Marianna Municipal Airport, 13 miles northwest. NOAA, through RCC-ACIS.
