The San Lorenzo 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.
3.00 inches of rain fell in two days, the most for this week of the year since records began in 1897. The next wettest, 2.25 inches, fell in 1913.
San Lorenzo’s center stands about 5,690 ft above sea level. Within three miles the land runs from 5,630 ft to 6,860 ft, a difference of 1,230 ft: steep hill country. The highest named summit within 15 miles is Hillsboro, about 10,010 ft, 13 miles northeast.
Under the town center the state geologic map shows Alluvium (unconsolidated), from the Pleistocene to Holocene, less than 0.1 million years old.
The section below crosses 7 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 6×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Felsic-volcanic. Age: Late Eocene to Early Oligocene, 31 to 36 million years old. About 11 mi of the line.
Andesite, basaltic-andesite, basalt. Age: Early Oligocene to Late Oligocene, 26 to 29 million years old. About 3 mi of the line.
Conglomerate-sandstone, volcanic. Age: Late Oligocene to Pleistocene, 0.1 to 28 million years old. About 3 mi of the line.
Andesite, latite. Age: Middle Eocene to Early Oligocene, 33 to 43 million years old. About 2 mi of the line.
Unconsolidated. Age: Pleistocene to Holocene, less than 0.1 million years old. About 2 mi of the line.
Sedimentary. Age: Cambrian to Silurian, 422 to 542 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. 1 smaller unit 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.
San Lorenzo has a cold semi-arid climate. Summer afternoons average 90° in June; winter nights fall to about 30° in December. About 16 inches of rain fall in a normal year.
On November 14 San Lorenzo normally reaches 64° and falls to 38°. The record high is 78°, in 1953; the record low 13°, in 1916. The most rain on this date, 0.75 in, fell in 1968.
Normals 1991–2020 and records since 1897 at Fort Bayard 4 W, 18 miles west, 460 ft higher. NOAA, through RCC-ACIS.