Mean monthly frequency (%) of clear and overcast sky conditions (midnight to midnight observations).
64° 31'N / 165° 27' W
13.1 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 0.40 to 0.70, and cloudy skies 0.80 to 1.00.
Mean monthly frequency (%) of clear, partly cloudy, and cloudy sky condition and mean cloudiness (fraction of sky coverage).
| Sky Condition |
Jan
|
Feb
|
Mar
|
Apr
|
May
|
Jun
|
Jul
|
Aug
|
Sep
|
Oct
|
Nov
|
Dec
|
| Clear |
43
|
49
|
47
|
42
|
30
|
31
|
22
|
18
|
23
|
31
|
37
|
36
|
| Partly Cloudy |
7
|
7
|
7
|
10
|
12
|
13
|
11
|
11
|
11
|
10
|
8
|
8
|
| Cloudy |
50
|
44
|
46
|
48
|
58
|
56
|
67
|
71
|
66
|
59
|
55
|
56
|
|
Mean Cloudiness
|
0.54
|
0.49
|
0.51
|
0.55
|
0.65
|
0.64
|
0.73
|
0.77
|
0.73
|
0.65
|
0.60
|
0.61
|