10 



>J^ 



>J-^ 



/5 



36.1 



3Z.5 



34:G 



34.0 



33.1 



ZO 



Figure 2.— March weather diagram. Lower figures show day of month; the next upper band shows 

 average daily temperature in ° F.; the next band contains the record of the atmospheric pressure; the 

 next upper one indicates the degree of visibility (black areas for visibility of less than 2 nautical miles 

 and lined areas for visibility between 2 and 4 miles. The upper margin shows the average direction and 

 force of the wind for 12-hour periods, midnight to noon and noon to midnight. The wind directions are 

 toward the center in each case. The top of page is north. The figures indicate the average force of the 

 wind in the Beaufort scale. 



APRIL 



Maximum air temperature 39° F. 



Minimum air temperature 27° F. 



Average air temperature 32.9° F. 



Visibility was less than 4 miles 44.4 percent of the time. 



Visibility was less than 2 miles 24.6 percent of the time. 



Figure 3 shows the detailed weather conditions for April, 



^4 



4 



^/^ 



M^ 



6 





>: 



35.& 



38.8 



33.7 



34.4 



38.7 



39-9 



38.0 



36.& 



34.7 



35.6 



37.8 



3S.9 



33.7 



38.3 



4-1.0 



/O 



II 



IZ 



13 



14- 



15 



16 



17 



Z7 



Z8 



Z9 



30 



31 



Figure 3. — April weather diagram. For explanation of symbols see figure 2. 

 MAY 



Maximum air temperature 47° F. 



Minimum air temperature 32° F. 



Average air temperature 37.4° F. 



Visibility less than 4 miles 33.1 percent of the time. 



Visibility less than 2 miles 15.7 percent of the time. 



Figure 4 shows the detailed weather conditions for May. 



Figure 4. — May weather diagram. For explanation of symbols see figure 2. 



