The Harrison 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 cloudy
Partly cloudy; warmer
Partly cloudy
Mostly sunny
Mostly sunny
Mostly sunny
Partly cloudy
74° on Nov. 11, 2002, the hottest reading for this week of the year since 1996. Next is 74° in 2022.
Harrison’s center stands about 310 ft above sea level. Within three miles the land runs from 260 ft to 850 ft, a difference of 590 ft: hilly country. The highest named summit within 15 miles is Pleasant Mountain, about 1,990 ft, 9 miles southwest.
Under the town center the state geologic map shows Carboniferous alkali feldspar granite (muscovite accessory mineral), from the Carboniferous, 299 to 359 million years old.
The section below crosses 2 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 18×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Granite. Age: Carboniferous, 299 to 359 million years old. About 23 mi of the line.
Granite. Age: Carboniferous, 299 to 359 million years old. About 0.8 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 Harrison reaches the Atlantic Ocean by way of Carsley Brook, Whitney Brook and the Presumpscot: about 55 river miles.
Lake on the way: Sebago Lake Basin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Harrison; river miles along the main stem, rounded.
Harrison has a warm-summer humid continental climate. Summer afternoons average 82° in July; winter nights fall to about 7° in January. About 47 inches of rain fall in a normal year.
On November 14 Harrison normally reaches 47° and falls to 26°. The record high is 63°, in 2016; the record low 4°, in 2019. The most rain on this date, 2.06 in, fell in 2009.
Normals 1991–2020 and records since 1996 at Fryeburg Eastern Slopes Regl Airport, 16 miles west-southwest, 140 ft higher. NOAA, through RCC-ACIS.
