southeast, while greatest mean wind speeds are recorded from south-southwest 
to west-northwest. 
The mean tenths of total sky cover is fairly uniform throughout the year, 
ranging from a low of 5•3 in August to a high of 7*3 in March. The yearly mean 
is 6.2. The occurrence of fog and haze is negligible, but highest in January 
and March. Closed conditions with visibility less than one mile occur rarely 
(2 o/o) at Midway, but most often from December through April, when due to rain. 
