The Nyssa 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
Showers likely
Showers likely
Mostly sunny
Showers likely
Chance of showers
Partly cloudy
−3° on Nov. 17, 2014, the coldest reading for this week of the year since 1931. Next is 2° in 1955.
Nyssa’s center stands about 2,180 ft above sea level. Within three miles the land runs from 2,160 ft to 2,370 ft, a difference of 210 ft: rolling country. The highest named summit within 15 miles is Mitchell Butte, about 3,480 ft, 12 miles southwest.
Under the town center the state geologic map shows Alluvial deposits (sand, gravel, silt), from the Holocene, less than 12,000 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 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.
Sandstone, siltstone, mudstone. Age: Miocene to Pliocene, 2.6 to 23 million years old. About 8 mi of the line.
Coarse-detrital, fine-detrital. Age: Pleistocene to Holocene, less than 33,000 years old. About 7 mi of the line.
Sand, gravel, silt. Age: Holocene, less than 12,000 years old. About 4 mi of the line.
Mixed-clastic. Age: Early Miocene to Late Miocene, 8 to 17 million years old. About 3 mi of the line.
Gravel, boulders, fine-detrital. Age: Pliocene to Pleistocene, less than 5.3 million years old. About 0.7 mi of the line.
Gravel, sand, silt. Age: Quaternary, less than 2.6 million years old. About 0.4 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 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 Nyssa reaches the Pacific Ocean by way of Plummer Slough, the Snake and the Columbia: about 700 river miles.
Lakes on the way: Lake Umatilla, Brownlee Reservoir and Hells Canyon Reservoir.
240 miles of the trip are on the Snake.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Nyssa; river miles along the main stem, rounded.
Nyssa has a cold semi-arid climate. Summer afternoons average 95° in July; winter nights fall to about 24° in January. About 10 inches of rain fall in a normal year.
On November 14 Nyssa normally reaches 50° and falls to 30°. The record high is 65°, in 1953; the record low 7°, in 1978. The most rain on this date, 0.58 in, fell in 1965.
Normals 1991–2020 and records since 1931 from the Ontario Area threaded record (Ontario, 9 miles north). NOAA, through RCC-ACIS.
