The San Leanna 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
Mostly sunny; warmer
Mostly cloudy
Chance of showers
Partly cloudy
24° on Nov. 14, 2018, the coldest reading for this week of the year since 1942. Next is 25° in 2014.
San Leanna’s center stands about 690 ft above sea level. Within three miles the land runs from 580 ft to 780 ft, a difference of 200 ft: rolling country. The highest named summit within 15 miles is Chalk Knob, about 1,180 ft, 14 miles northwest.
Under the town center the state geologic map shows Austin Chalk (marlstone, chalk), from the Late Cretaceous, 66 to 100 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 29×. 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, siltstone-mudstone. Age: Late Cretaceous, 66 to 100 million years old. About 6 mi of the line.
Limestone, marlstone. Age: Early Cretaceous, 100 to 145 million years old. About 5 mi of the line.
Limestone. Age: Early Cretaceous, 100 to 113 million years old. About 4 mi of the line.
Limestone, carbonate. Age: Late Cretaceous, 66 to 72 million years old. About 3 mi of the line.
Marlstone, chalk. Age: Late Cretaceous, 66 to 100 million years old. About 2 mi of the line.
Sand. Age: Pleistocene to Holocene, less than 2.6 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. 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 San Leanna reaches the Gulf of America by way of Slaughter Creek, Onion Creek and the Colorado: about 300 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of San Leanna; river miles along the main stem, rounded.
San Leanna has a humid subtropical climate. Summer afternoons average 97° in August; winter nights fall to about 38° in January. About 36 inches of rain fall in a normal year.
On November 14 San Leanna normally reaches 72° and falls to 47°. The record high is 89°, in 2020; the record low 24°, in 2018. The most rain on this date, 0.87 in, fell in 1998.
Normals 1991–2020 and records since 1942 from the Austin-Bergstrom Airport Area threaded record (Austin-Camp Mabry, 13 miles north-northeast). NOAA, through RCC-ACIS.
