The East Porterville 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.
88° on Nov. 12, 2016, the hottest reading for this week of the year since 1913. Next is 84° in 1953.
East Porterville’s center stands about 490 ft above sea level. Within three miles the land runs from 450 ft to 1,590 ft, a difference of 1,140 ft: steep hill country. The highest named summit within 15 miles is Black Mountain, about 6,310 ft, 14 miles east-northeast.
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 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.
Coarse-detrital. Age: Pleistocene to Holocene, less than 2.6 million years old. About 12 mi of the line.
Granodiorite. Age: Permian to Tertiary, 2.6 to 260 million years old. About 5 mi of the line.
Coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 3 mi of the line.
Schist, gneiss. Age: Paleoproterozoic to Cretaceous, 66 to 2,500 million years old. About 2 mi of the line.
Peridotite, serpentinite. Age: Neoproterozoic to Early Jurassic, 175 to 1,000 million years old. About 2 mi of the line.
Basalt, serpentinite. Age: Ordovician to Permian, 252 to 487 million years old. About 0.6 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 East Porterville reaches the Tulare Lake basin by way of the North Branch Tule and the Tule: about 55 river miles. The Tulare Lake basin has no outlet to the sea: the water leaves only by evaporating or soaking into the ground.
Often dry. About 70% of the way is mapped as streams that run only after rain or snowmelt; the water makes the whole trip in floods.
A lake that comes back. The bed of Tulare Lake is farmland now; in very wet years it floods again.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of East Porterville; river miles along the main stem, rounded.
East Porterville has a cold semi-arid climate. Summer afternoons average 96° in July; winter nights fall to about 36° in December. About 12 inches of rain fall in a normal year.
On November 14 East Porterville normally reaches 66° and falls to 42°. The record high is 81°, in 2025; the record low 24°, in 1916. The most rain on this date, 0.98 in, fell in 1953.
Normals 1991–2020 and records since 1913 at Lindsay, 11 miles north-northwest. NOAA, through RCC-ACIS.