Flagstaff is the original International Dark Sky City, with high-elevation pine forests and Lowell Observatory heritage. Cold, dry winters deliver some of the Southwest’s steadiest transparency.
Summer monsoon moisture still rolls in from the south each afternoon.
United States · Arizona · first International Dark Sky City
Check the live Tonight score for Flagstaff (cloud, dew, transparency, and astronomical dark), then read the hourly cloud timing chart and moonless dark window on this page.
Use the best clear window clock times after astronomical darkness, and prefer moonless hours when deep-sky contrast matters.
This hub shows moonrise, moonset, illumination, and the longest moonless astronomical-dark interval for Flagstaff. Open Dark Sky Window for the full ephemeris card.
ISS passes are spottable near dusk or dawn when the sky is dark and the station is still sunlit. This page lists the next spottable pass when available.
Learn: Is tonight good for stargazing? · How to see the Milky Way