StarsOutAlert me on good nights
Should you go outside tonight?
Probably not tonight
Too much cloud cover for a good session.
Ostrava
4.2
out of 10
Cautious estimate
Models split — score biased toward the cloudier forecast.
Peak 2h
6.200:00–02:00
Prime 21–01
4.821:00–01:00
Best this week
8.1Sat, Jun 6
Moon
Waning Gibbous
98% lit
Very bright — stick to planets and the moon itself
🔭 Moon up: 21:36–04:43
📍 SW · 2°
Sky now
Clear · 0%
Measured at LKMT · 18km away · 19min ago
Sun ↓ 20:46·Dark from 21:46·65% clouds
🔭
Moon visible today
04:42 – 07:26 · 98% lit · great for telescope viewing
Next great night
Saturday — 8.1
✨ Great night tonight
Sky quality tonight
Best: 00:00–02:00This week’s nights
Europe/PragueHow the score works
60% weight
Cloud cover
Layer-weighted across the best 2-hour window of the night. Low clouds block everything, thin high cirrus still lets bright stars through.
40% weight
Moon darkness
A new moon boosts the score. A full moon near midnight washes out all but the brightest stars. We ease the penalty after midnight when the moon is setting.