Eight-week planning horizon
Choose your observing weekend
Grande Prairie · ranked by total moonless dark hours across Friday and Saturday. Seasonal history is context, not the chance of clear weather on those dates.
Moonless time rank 14 Dec – 5 Dec
23.0h moonless / 24.0h astronomical darkness across both nights
December seasonal context
0.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
11.0h moonless · Moon 13% lit
Longest moonless stretch: 20:00–07:00
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
12.0h moonless · Moon 7% lit
Longest moonless stretch: 20:00–08:00
Weather not available for this night. Geometry only; recheck nearer departure.
Moonless time rank 26 Nov – 7 Nov
22.0h moonless / 22.0h astronomical darkness across both nights
November seasonal context
0.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
11.0h moonless · Moon 4% lit
Longest moonless stretch: 20:20–07:20
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
11.0h moonless · Moon 1% lit
Longest moonless stretch: 20:20–07:20
Weather not available for this night. Geometry only; recheck nearer departure.
Moonless time rank 313 Nov – 14 Nov
19.7h moonless / 22.0h astronomical darkness across both nights
November seasonal context
0.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
10.3h moonless · Moon 22% lit
Longest moonless stretch: 21:00–07:20
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
9.3h moonless · Moon 30% lit
Longest moonless stretch: 22:00–07:20
Weather not available for this night. Geometry only; recheck nearer departure.
Moonless time rank 416 Oct – 17 Oct
16.3h moonless / 19.3h astronomical darkness across both nights
October seasonal context
2.5 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
8.7h moonless · Moon 37% lit
Longest moonless stretch: 22:00–06:40
Forecast cloud range: 13–91% at 2 available dark-time samples. Not full-night coverage or a probability.
Saturday
7.7h moonless · Moon 47% lit
Longest moonless stretch: 23:00–06:40
Weather not available for this night. Geometry only; recheck nearer departure.
Moonless time rank 530 Oct – 31 Oct
3.0h moonless / 20.7h astronomical darkness across both nights
October seasonal context
2.5 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
0.7h moonless · Moon 69% lit
Longest moonless stretch: 20:40–21:20
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
2.3h moonless · Moon 58% lit
Longest moonless stretch: 20:40–23:00
Weather not available for this night. Geometry only; recheck nearer departure.
Moonless time rank 627 Nov – 28 Nov
2.3h moonless / 23.3h astronomical darkness across both nights
November seasonal context
0.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
0.3h moonless · Moon 83% lit
Longest moonless stretch: 20:00–20:20
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
2.0h moonless · Moon 73% lit
Longest moonless stretch: 20:00–22:00
Weather not available for this night. Geometry only; recheck nearer departure.
Moonless time rank 720 Nov – 21 Nov
1.3h moonless / 23.3h astronomical darkness across both nights
November seasonal context
0.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
1.3h moonless · Moon 86% lit
Longest moonless stretch: 06:20–07:40
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
0.0h moonless · Moon 92% lit
No moonless dark window
Weather not available for this night. Geometry only; recheck nearer departure.
No moonless darkness23 Oct – 24 Oct
0.0h moonless / 20.7h astronomical darkness across both nights
October seasonal context
2.5 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.
Night-by-night timing & conditions
Friday
0.0h moonless · Moon 95% lit
No moonless dark window
Weather not available for this night. Geometry only; recheck nearer departure.
Saturday
0.0h moonless · Moon 99% lit
No moonless dark window
Weather not available for this night. Geometry only; recheck nearer departure.