The Hillsboro 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.
Partly cloudy
Mostly sunny
Mostly sunny
Showers likely
Sunny
Mostly sunny
Mostly sunny
3.14 inches of rain fell in two days, the most for this week of the year since records began in 1893. The next wettest, 1.31 inches, fell in 2004.
Hillsboro’s center stands about 5,270 ft above sea level. Within three miles the land runs from 5,110 ft to 6,200 ft, a difference of 1,090 ft: steep hill country. The highest named summit within 15 miles is Hillsboro, about 10,010 ft, 13 miles west.
Under the town center the state geologic map shows Lower Santa Fe Group (conglomerate-sandstone, coarse-detrital, fine-detrital), from the Late Oligocene to Late Miocene, 5.3 to 28 million years old.
The section below crosses 14 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 5×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Conglomerate-sandstone, coarse-detrital, fine-detrital. Age: Late Miocene to Pleistocene, 0.1 to 7.2 million years old. About 9 mi of the line.
Conglomerate-sandstone, coarse-detrital, fine-detrital. Age: Late Oligocene to Late Miocene, 5.3 to 28 million years old. About 3 mi of the line.
Felsic-volcanic. Age: Late Eocene to Early Oligocene, 31 to 36 million years old. About 2 mi of the line.
Basaltic-andesite, rhyolite. Age: Late Oligocene to Early Miocene, 16 to 28 million years old. About 2 mi of the line.
Andesite, basaltic-andesite, basalt. Age: Early Oligocene to Late Oligocene, 26 to 29 million years old. About 2 mi of the line.
Limestone, dolostone, shale. Age: Cambrian to Carboniferous, 324 to 542 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. 8 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 Hillsboro reaches the Gulf of America by way of North Percha Creek, Percha Creek and the Rio Grande: about 1,380 river miles.
Lakes on the way: Paz Ramirez Lake, Amistad Reservoir and Caballo Reservoir.
760 miles of the trip are on the Rio Grande.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Hillsboro; river miles along the main stem, rounded.
Hillsboro has a cold semi-arid climate. Summer afternoons average 93° in June; winter nights fall to about 25° in January. About 12 inches of rain fall in a normal year, with about 3 inches of snow.
On November 14 Hillsboro normally reaches 64° and falls to 32°. The record high is 82°, in 2017; the record low 17°, in 2018. The most rain on this date, 0.38 in, fell in 1968.
Normals 1991–2020 and records since 1893 at Hillsboro, here. NOAA, through RCC-ACIS.
