170" 175' 180' 



170" 165° 



FIGURE 32. COMPOSITE VISIBILITY (MILES)-WINTER 1955 (5 MARCH THROUGH 18 APRIL) 



175° ISO" 175° 170 



165° 160° 



FIGURE 33. COMPOSITE VISIBILITY (MILES)— SPRING 1955 (21 APRIL THROUGH 27 MAY) 



