The Derrynane 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
Partly cloudy; warmer
Partly cloudy
Partly cloudy
Partly cloudy
Partly cloudy
Showers likely
74° on Nov. 13, 1999, the hottest reading for this week of the year since 1942. Next is 72° in 2012.
Derrynane’s center stands about 1,030 ft above sea level. Within three miles the land runs from 980 ft to 1,050 ft, a difference of 70 ft: gently rolling country.
Under the town center the state geologic map shows Upper Cambrian (sandstone, siltstone, shale), from the Cambrian, 487 to 497 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 46×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, siltstone, shale. Age: Cambrian, 487 to 497 million years old. About 17 mi of the line.
Sandstone, siltstone, shale. Age: Middle Cambrian to Cambrian, 487 to 521 million years old. About 4 mi of the line.
Dolostone, sandstone. Age: Early Ordovician, 471 to 487 million years old. About 4 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 Derrynane reaches the Gulf of America by way of the Raven Stream, Sand Creek, the Minnesota and the Mississippi: about 1,880 river miles.
Lake on the way: Lake Pepin.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Derrynane; river miles along the main stem, rounded.
Derrynane has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 5° in January. A normal year brings about 40 inches of snow; with the rain, that comes to about 33 inches of water.
On November 14 Derrynane normally reaches 42° and falls to 26°. The record high is 69°, in 1990; the record low −5°, in 1959. The most rain on this date, 1.23 in, fell in 2010.
Normals 1991–2020 and records since 1942 at Jordan 1 SSW, 11 miles north-northeast, 130 ft lower. NOAA, through RCC-ACIS.
