The Casas 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 cloudy; cooler
Mostly cloudy
Mostly cloudy
Partly cloudy
Partly cloudy
3.20 inches of rain fell in two days, the most for this week of the year since records began in 1892. The next wettest, 2.69 inches, fell in 2003.
Casas’s center stands about 370 ft above sea level. Within three miles the land runs from 220 ft to 440 ft, a difference of 220 ft: rolling country.
Under the town center the state geologic map shows Jackson Group, undivided (clay), from the Late Eocene to Early Oligocene, 28 to 38 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 53×. 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: Late Eocene to Early Oligocene, 28 to 38 million years old. About 13 mi of the line.
Clay. Age: Oligocene, 23 to 34 million years old. About 4 mi of the line.
Gravel. Age: Late Pliocene to Pleistocene, less than 3.6 million years old. About 2 mi of the line.
Sand. Age: Pleistocene to Holocene, less than 2.6 million years old. About 1 mi of the line.
Fine-detrital, coarse-detrital. Age: Holocene, less than 12,000 years old. About 1 mi of the line.
Claystone, sandstone. Age: Eocene, 34 to 56 million years old. About 0.9 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 Casas reaches the Gulf of America by way of the Arroyo Grande and the Rio Grande: about 250 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Casas; river miles along the main stem, rounded.
Casas has a hot semi-arid climate. Summer afternoons average 99° in July; winter nights fall to about 45° in January. About 22 inches of rain fall in a normal year.
On November 14 Casas normally reaches 79° and falls to 55°. The record high is 94°, in 1985; the record low 27°, in 2018. The most rain on this date, 0.56 in, fell in 1998.
Normals 1991–2020 and records since 1892 at Rio Grande City, 10 miles southeast, 200 ft lower. NOAA, through RCC-ACIS.
