Mean monthly frequency (%) of clear and overcast sky conditions (sunrise to sunset observations).
61° 12'N / 150° 00' W
114 ft. above sea level
midnight - midnight
sunrise - sunset
Analyses are based on hourly observations for the years 1971 - 1996.
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 |
23
|
28
|
28
|
24
|
17
|
16
|
15
|
17
|
17
|
19
|
23
|
17
|
| Partly Cloudy |
9
|
8
|
9
|
10
|
12
|
13
|
13
|
12
|
10
|
8
|
8
|
8
|
| Cloudy |
68
|
64
|
62
|
66
|
71
|
71
|
72
|
72
|
74
|
73
|
69
|
75
|
|
Mean Cloudiness
|
0.73
|
0.68
|
0.68
|
0.72
|
0.77
|
0.78
|
0.79
|
0.78
|
0.79
|
0.78
|
0.74
|
0.79
|