Monmouth, OR's night sky, measured from orbit
Satellite radiance puts Monmouth in the suburban edge band. A noticeable glow near the horizon. Brighter stars and constellations are easy to pick out; the Milky Way is washed out. That's brighter than 38.9% of the 3,206 US cities in this dataset.
Note the source: a satellite reading of upward light, not a visual Bortle scale reading. The two measure related but different things.
Where to go for a darker sky near Monmouth
The closest place in this dataset with a meaningfully darker sky is Independence, OR, roughly 2 miles away in a straight line, rated rural. Road distance will be more.
Independence, OR is itself still a measured city, not a designated dark-sky park, this only compares against the 3,206 places this dataset covers.
How Monmouth compares nationally
Monmouth, OR counts roughly 11,651 residents, among the 3,206 US cities this site tracks. Monmouth places 1,241 of 3,206 cities in this dataset's darkest-to-brightest order.