The Brockton 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.
Mostly sunny
Partly cloudy
Partly cloudy
Mostly cloudy
Showers likely; cooler
Mostly cloudy
Mostly cloudy
77° on Nov. 12, 1999, the hottest reading for this week of the year since 1900. Next is 72° in 1934.
Brockton’s center stands about 1,990 ft above sea level. Within three miles the land runs from 1,910 ft to 2,260 ft, a difference of 350 ft: rolling country. The highest named summit within 15 miles is Haystack Butte, about 2,410 ft, 8 miles south.
Under the town center the state geologic map shows Hell Creek Formation (sandstone, shale, bentonite), from the Late Cretaceous, 66 to 84 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 40×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Shale, sandstone, bentonite. Age: Early Paleocene, 62 to 66 million years old. About 7 mi of the line.
Sandstone. Age: Early Paleocene, 62 to 66 million years old. About 7 mi of the line.
Sandstone, shale, bentonite. Age: Late Cretaceous, 66 to 84 million years old. About 6 mi of the line.
Gravel, sand, silt. Age: Pleistocene to Holocene, less than 1.8 million years old. About 2 mi of the line.
Sandstone, shale. Age: Early Paleocene to Middle Paleocene, 59 to 66 million years old. About 2 mi of the line.
Sandstone, siltstone, black-shale. Age: Late Cretaceous, 66 to 84 million years old. About 0.3 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.
A raindrop that lands in Brockton reaches the Gulf of America by way of the Missouri and the Mississippi: about 2,810 river miles.
Lakes on the way: Lake Oahe, Lake Sakakawea, Lake Sharpe and Lake Francis Case.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Brockton; river miles along the main stem, rounded.
Brockton has a cold semi-arid climate. Summer afternoons average 87° in July; winter nights fall to about 2° in January. About 14 inches of rain fall in a normal year.
On November 14 Brockton normally reaches 41° and falls to 18°. The record high is 66°, in 1934; the record low −19°, in 2014. The most rain on this date, 0.48 in, fell in 1906.
Normals 1991–2020 and records since 1900 at Culbertson, 18 miles east. NOAA, through RCC-ACIS.
