The Cortlandt 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.
Partly cloudy
Mostly sunny; warmer
Partly cloudy
Sunny
Sunny
Mostly sunny
Mostly sunny
77° on Nov. 11, 2020, the hottest reading for this week of the year since 1950. Next is 69° in 2022.
Cortlandt’s center stands about 280 ft above sea level. Within three miles the land runs from 0 ft to 670 ft, a difference of 670 ft: hilly country. Open water lies within three miles. The highest named summit within 15 miles is Schunnemunk Mountain, about 1,540 ft, 15 miles northwest.
Under the town center the state geologic map shows Hornblende norite, from the Late Ordovician, 445 to 459 million years old.
The section below crosses 13 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 19×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Gneiss, quartzite. Age: Mesoproterozoic, 1 to 1.6 billion years old. About 4 mi of the line.
Norite. Age: Late Ordovician, 445 to 459 million years old. About 3 mi of the line.
Biotite-gneiss. Age: Mesoproterozoic, 1 to 1.6 billion years old. About 2 mi of the line.
Basalt. Age: Early Jurassic, 175 to 202 million years old. About 1 mi of the line.
Pelitic-schist, gneiss, amphibolite. Age: Early Cambrian to Middle Ordovician, 459 to 542 million years old. About 1 mi of the line.
Gneiss. Age: Precambrian to Mesoproterozoic. About 1 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 7 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 Cortlandt reaches New York Harbor and the Atlantic Ocean by way of Furnace Brook and the Hudson: about 40 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Cortlandt; river miles along the main stem, rounded.
Cortlandt has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 17° in January. About 50 inches of rain fall in a normal year.
On November 14 Cortlandt normally reaches 53° and falls to 32°. The record high is 68°, in 1964; the record low 17°, in 2019. The most rain on this date, 1.18 in, fell in 1955.
Normals 1991–2020 and records since 1950 at Shrub Oak, 7 miles north-northeast, 180 ft higher. NOAA, through RCC-ACIS.
