The St. Hedwig 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
21° on Nov. 14, 2018, the coldest reading for this week of the year since 1948. Next is 25° in 1969.
St. Hedwig’s center stands about 600 ft above sea level. Within three miles the land runs from 500 ft to 640 ft, a difference of 140 ft: gently rolling country. The highest named summit within 15 miles is Rocky Point, about 790 ft, 9 miles south.
Under the town center the state geologic map shows Wilcox Group, undivided (mudstone), from the Late Paleocene to Early Eocene, 48 to 59 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 42×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Mudstone. Age: Late Paleocene to Early Eocene, 48 to 59 million years old. About 10 mi of the line.
Clay, siltstone-mudstone. Age: Late Cretaceous, 66 to 100 million years old. About 8 mi of the line.
Sand. Age: Pleistocene to Holocene, less than 2.6 million years old. About 2 mi of the line.
Sandstone. Age: Eocene, 34 to 56 million years old. About 2 mi of the line.
Limestone, carbonate. Age: Late Cretaceous, 66 to 72 million years old. About 1 mi of the line.
Coarse-detrital, fine-detrital. Age: Pleistocene, less than 2.6 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 St. Hedwig reaches the Gulf of America by way of Dry Hollow Creek, Cibolo Creek, the San Antonio, the Guadalupe and the South Guadalupe: about 200 river miles.
130 miles of the trip are on the San Antonio.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of St. Hedwig; river miles along the main stem, rounded.
St. Hedwig has a hot desert climate. Summer afternoons average 96° in July; winter nights fall to about 41° in January. Barely 0.0 inches of rain fall in a normal year.
Normals 1991–2020 and records since 1948 at Randolph Afb, 8 miles north-northwest, 130 ft higher. NOAA, through RCC-ACIS.
