The Purty Rock 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.
Mostly sunny
Mostly sunny
Mostly sunny
Showers likely
Mostly sunny; cooler
Partly cloudy
Chance of showers; cooler
2° on Nov. 12, 2000, the coldest reading for this week of the year since 1973. Next is 2° in 2018.
Purty Rock’s center stands about 6,370 ft above sea level. Within three miles the land runs from 6,310 ft to 6,960 ft, a difference of 650 ft: hilly country. The highest named summit within 15 miles is Remnant Mesa, about 7,260 ft, 8 miles east-southeast.
Under the town center the state geologic map shows Crevasse Canyon Formation (shale, sandstone), from the Late Cretaceous, 84 to 90 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 19×. 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: Late Cretaceous, 84 to 90 million years old. About 13 mi of the line.
Sandstone. Age: Late Cretaceous, 90 to 94 million years old. About 6 mi of the line.
Sandstone, shale. Age: Late Cretaceous, 88 to 97 million years old. About 3 mi of the line.
Shale, limestone. Age: Late Cretaceous, 90 to 94 million years old. About 2 mi of the line.
Sandstone, siltstone. Age: Early Jurassic to Late Jurassic, 160 to 180 million years old. About 0.1 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 Purty Rock reaches the Gulf of California by way of the Puerco, the Little Colorado and the Colorado: about 1,050 river miles.
Lakes on the way: Lake Mead, Lake Mohave and Lake Havasu.
290 miles of the trip are on the Colorado.
Often dry. About 30% of the way is mapped as streams that run only after rain or snowmelt; the water makes the whole trip in floods.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Purty Rock; river miles along the main stem, rounded.
Purty Rock has a cold semi-arid climate. Summer afternoons average 89° in July; winter nights fall to about 14° in January. A normal year brings about 34 inches of snow; with the rain, that comes to about 11 inches of water.
On November 14 Purty Rock normally reaches 56° and falls to 20°. The record high is 73°, in 1999; the record low 4°, in 2000. The most rain on this date, 0.44 in, fell in 1997.
Normals 1991–2020 and records since 1973 at Gallup Municipal Airport, 6 miles east-northeast. NOAA, through RCC-ACIS.
