The Leon Valley 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.
Chance of showers
Showers likely
Mostly cloudy; cooler
Partly cloudy
Mostly cloudy
Chance of showers
Partly cloudy
23° on Nov. 14, 2018, the coldest reading for this week of the year since 1885. Next is 26° in 1950.
Leon Valley’s center stands about 820 ft above sea level. Within three miles the land runs from 760 ft to 1,030 ft, a difference of 270 ft: rolling country. The highest named summit within 15 miles is Black Hill, about 1,590 ft, 10 miles northwest.
Under the town center the state geologic map shows Pecan Gap Chalk (limestone, carbonate), from the Late Cretaceous, 66 to 72 million years old.
The section below crosses 8 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 21×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sand. Age: Pleistocene to Holocene, less than 2.6 million years old. About 7 mi of the line.
Limestone. Age: Early Cretaceous, 100 to 113 million years old. About 5 mi of the line.
Limestone, carbonate. Age: Late Cretaceous, 66 to 72 million years old. About 5 mi of the line.
Marlstone, chalk. Age: Late Cretaceous, 66 to 100 million years old. About 3 mi of the line.
Clay, siltstone-mudstone. Age: Late Cretaceous, 66 to 100 million years old. About 3 mi of the line.
Limestone. Age: Late Cretaceous, 66 to 100 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. 2 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 Leon Valley reaches the Gulf of America by way of Huebner Creek, Leon Creek, the Medina, the San Antonio, the Guadalupe and the South Guadalupe: about 260 river miles.
210 miles of the trip are on the San Antonio.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Leon Valley; river miles along the main stem, rounded.
Leon Valley has a humid subtropical climate. Summer afternoons average 96° in August; winter nights fall to about 41° in January. About 32 inches of rain fall in a normal year.
On November 14 Leon Valley normally reaches 72° and falls to 50°. The record high is 89°, in 1983; the record low 23°, in 2018. The most rain on this date, 1.59 in, fell in 1923.
Normals 1991–2020 and records since 1885 from the San Antonio Area threaded record (San Antonio International Airport, 9 miles east-northeast). NOAA, through RCC-ACIS.
