Mean monthly frequency (%) of clear and overcast sky conditions (midnight to midnight observations).
51° 53'N / 176° 39' W
17.1 ft. above sea level
midnight - midnight
sunrise - sunset
Analyses are based on hourly observations for the years 1971 - 1994.
Clear skies are defined as 0 to 0.30 coverage, partly cloudy 0.4 to 0.70, and cloudy skies 0.80 to 1.00.
Mean monthly frequency (%) of clear, partly cloudy, and cloudy sky conditions and mean cloudiness (fraction of sky coverage).
| Sky Condition |
Jan
|
Feb
|
Mar
|
Apr
|
May
|
Jun
|
Jul
|
Aug
|
Sep
|
Oct
|
Nov
|
Dec
|
| Clear |
6
|
5
|
3
|
2
|
2
|
2
|
1
|
3
|
5
|
5
|
6
|
8
|
| Partly Cloudy |
11
|
8
|
8
|
6
|
4
|
3
|
4
|
4
|
7
|
11
|
12
|
10
|
| Cloudy |
83
|
87
|
89
|
92
|
94
|
95
|
95
|
93
|
88
|
84
|
82
|
82
|
|
Mean Cloudiness
|
86
|
88
|
89
|
91
|
92
|
94
|
94
|
92
|
89
|
86
|
85
|
85
|