The Sapphire 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.
Partly cloudy
Partly cloudy
Mostly cloudy
Showers likely; cooler
Mostly sunny
Chance of showers
Chance of showers
−15° on Nov. 13, 2014, the coldest reading for this week of the year since 1965. Next is −9° in 1966.
Sapphire Ridge’s center stands about 4,880 ft above sea level. Within three miles the land runs from 4,740 ft to 6,140 ft, a difference of 1,400 ft: steep hill country. The highest named summit within 15 miles is Yogo Peak, about 8,790 ft, 14 miles west-northwest.
Under the town center the state geologic map shows Otter Formation (shale, limestone), from the Middle Mississippian to Late Mississippian, 324 to 347 million years old.
The section below crosses 13 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 6×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Limestone. Age: Middle Mississippian, 331 to 347 million years old. About 5 mi of the line.
Age: Late Miocene to Holocene, less than 7.2 million years old. About 4 mi of the line.
Limestone. Age: Early Mississippian to Middle Mississippian, 331 to 359 million years old. About 3 mi of the line.
Shale, limestone. Age: Middle Mississippian to Late Mississippian, 324 to 347 million years old. About 3 mi of the line.
Sandstone, siltstone, shale. Age: Middle Mississippian, 331 to 347 million years old. About 2 mi of the line.
Limestone, mudstone, sandstone. Age: Middle Jurassic to Early Cretaceous, 129 to 172 million years old. About 2 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 7 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 Sapphire Ridge reaches the Gulf of America by way of the Judith, the Missouri and the Mississippi: about 3,270 river miles.
Lakes on the way: Lake Oahe, Lake Sakakawea, Lake Fort Peck and Lake Sharpe.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Sapphire Ridge; river miles along the main stem, rounded.
Sapphire Ridge has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 16° in January. About 17 inches of rain fall in a normal year.
On November 14 Sapphire Ridge normally reaches 46° and falls to 23°. The record high is 74°, in 1999; the record low −12°, in 2014. The most rain on this date, 0.08 in, fell in 2008.
Normals 1991–2020 and records since 1965 at Stanford, 19 miles north, 590 ft lower. NOAA, through RCC-ACIS.
