The Plaistow 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.
77° on Nov. 11, 2020, the hottest reading for this week of the year since 1899. Next is 75° in 1993.
Plaistow’s center stands about 110 ft above sea level. Within three miles the land runs from 50 ft to 380 ft, a difference of 330 ft: rolling country. The highest named summit within 15 miles is Warner Hill, about 620 ft, 9 miles west-northwest.
Under the town center the state geologic map shows Merrimack Group, Berwick Formation (granofels, biotite-schist), from the Ordovician to Silurian, 422 to 487 million years old.
The section below crosses 12 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 32×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Granofels, biotite-schist. Age: Ordovician to Silurian, 422 to 487 million years old. About 12 mi of the line.
Metaclastic. Age: Silurian, 422 to 445 million years old. About 3 mi of the line.
Phyllite. Age: Silurian, 422 to 445 million years old. About 3 mi of the line.
Granite, granodiorite. Age: Silurian, 422 to 445 million years old. About 1 mi of the line.
Tonalite, diorite. Age: Silurian, 425 to 435 million years old. About 1 mi of the line.
Granite. Age: Silurian, 422 to 445 million years old. About 0.9 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 6 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 Plaistow reaches the Atlantic Ocean by way of the Merrimack: about 25 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Plaistow; river miles along the main stem, rounded.
Plaistow has a hot-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 16° in January. A normal year brings about 58 inches of snow; with the rain, that comes to about 50 inches of water.
On November 14 Plaistow normally reaches 51° and falls to 31°. The record high is 74°, in 1989; the record low 11°, in 1986. The most rain on this date, 1.85 in, fell in 1995.
Normals 1991–2020 and records since 1899 at Haverhill, 6 miles south-southeast. NOAA, through RCC-ACIS.