Free Tonight score for any location: cloud, dew, transparency, the Moon, and Go / Maybe / Skip, so you know if tonight is worth the drive.
Frequently asked questions
Is tonight good for stargazing?
Use the Tonight score: 70+ is Go, 45-69 Maybe, under 45 Skip. It weighs cloud cover, dew risk, transparency, astronomical dark hours, and the Moon, minus a rain penalty. Open Stargazing Weather for hourly detail.
How is the Tonight score calculated?
It scores forecast cloud (40 of 100 points), dew risk, aerosol transparency, astronomical-dark hours and the Moon, adds 5 for a clear window soon, and subtracts up to 15 for rain risk. It leaves out light pollution; Sky Events adds Bortle.
Does this work outside Guyana?
Yes. Set any latitude and longitude. Guyana is the default demo because humid tropical nights need dew-aware scoring that still works worldwide.