Mean monthly frequency (%) of clear and overcast sky conditions (sunrise to sunset observations).
58° 41'N / 156° 39' W
46.9 ft. above sea level
midnight - midnight
sunrise - sunset
Analyses are based on hourly observations for the years 1971 - 1998.
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 |
26
|
31
|
28
|
19
|
12
|
8
|
6
|
7
|
9
|
20
|
22
|
19
|
| Partly Cloudy |
12
|
13
|
13
|
15
|
14
|
14
|
12
|
13
|
14
|
15
|
13
|
12
|
| Cloudy |
62
|
56
|
59
|
66
|
73
|
79
|
81
|
80
|
77
|
65
|
66
|
69
|
|
Mean Cloudiness
|
0.69
|
0.64
|
0.67
|
0.74
|
0.80
|
0.84
|
0.86
|
0.86
|
0.83
|
0.74
|
0.73
|
0.75
|