Click here or anywhere on the Clear Sky Clock for more information on the chart with in-depth explanations,
links to a local map of light pollution, transparency  and seeing forecasts, sun & moon data,  and much more...

(The Clear Sky Clock is brought to you courtesy of Attilla Danko and the Canadian Meteorological Center)  Be shure to thank them!

Cover Overcast 98% 80% 70% 60% 50% 40% 30% 20% 10% Clear
Transparency Poor Below Average Average Above Average Transparent
Seeing Bad [1/5] Poor [2/5] Average [3/5] Good [4/5] Excellent [5/5]
Darkness -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 3.5 4.0 4.5 5.0 5.2 5.4 5.6 5.8 6.0
Wind more than 45 mph 29 to 45 mph 17 to 28 mph 12 to 16 mph 6 to 11 mph 0 to 5 mph
Humidity less
than
25%		 25%
to
30%		 30%
to
35%		 35%
to
40%		 40%
to
45%		 45%
to
50%		 50%
to
55%		 55%
to
60%		 60%
to
65%		 65%
to
70%		 70%
to
75%		 75%
to
80%		 80%
to
85%		 85%
to
98%		 98%
to
95%		 95%
to
100%
Temperature less
than
-40F		 -40F
to
-31F		 -30F
to
-21F		 -21F
to
-12F		 -12F
to
-3F		 -3F
to
5F		 5F
to
14F		 14F
to
23F		 23F
to
32F		 32F
to
41F		 41F
to
50F		 50F
to
59F		 59F
to
68F		 68F
to
77F		 77F
to
86F		 86F
to
95F		 95F
to
104F		 104F
to
113F		 more
than
113F