The Willis 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.
6.52 inches of rain fell in two days, the most for this week of the year since records began in 1897. The next wettest, 5.13 inches, fell in 2003.
Willis’s center stands about 380 ft above sea level. Within three miles the land runs from 260 ft to 410 ft, a difference of 150 ft: gently rolling country.
Under the town center the state geologic map shows Willis Formation (coarse-detrital, fine-detrital), from the Pliocene, 2.6 to 5.3 million years old.
The section below crosses 5 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Coarse-detrital, fine-detrital. Age: Pliocene, 2.6 to 5.3 million years old. About 13 mi of the line.
Clay, sandstone. Age: Miocene, 5.3 to 23 million years old. About 8 mi of the line.
Fine-detrital, coarse-detrital. Age: Holocene, less than 12,000 years old. About 2 mi of the line.
Coarse-detrital, fine-detrital. Age: Pleistocene to Holocene, less than 2.6 million years old. About 1 mi of the line.
Sand. Age: Pleistocene, less than 2.6 million years old. About 0.2 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
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 Willis reaches Galveston Bay and the Gulf of America by way of Camp Creek, Caney Creek, the San Jacinto and Buffalo Bayou: about 75 river miles.
Lake on the way: Lake Houston.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Willis; river miles along the main stem, rounded.
Willis has a humid subtropical climate. Summer afternoons average 96° in August; winter nights fall to about 42° in January. About 51 inches of rain fall in a normal year.
On November 14 Willis normally reaches 72° and falls to 51°. The record high is 89°, in 1959; the record low 21°, in 1982. The most rain on this date, 1.46 in, fell in 1920.
Normals 1991–2020 and records since 1897 at Conroe, 7 miles south, 140 ft lower. NOAA, through RCC-ACIS.