13 

 Code Table XVI 



Symbol C — Form of predominating cloud 



Code 

 figures 



Code Table XVII 



Symbol N — Total amount of all clouds 



(Regardless of kind of clouds) 



Symbol A r L — Amount of lower cloud 



Proportion of sky covered (in tenths) 



0. 



Less than 0.1. 



0.1. 



0.2 to 0.3. 



0.4 to 0.6. 



0.7 to 0.8. 



0.9. 



More than 0.9 but with openings. 



Sky completely covered with clouds. 



Sky obscured by fog, duststorm, or other phenomenon. 



Code Table XVIII 



Symbol t a — Temperature difference {air and water) 

 (Difference between temperature of air and temperature of water at or near surface) 



Code 

 figures 







1 



2 

 3 

 4 



5 

 6 

 7 

 8 



More than 9° F 



6° to 9° 



3° to 6° 



1° to 3° 



No difference or less than 1° F. higher 



Less than 1° F 



1° to 3° 



3° to 6° 



6° to 9° 



More than 9° 



Air temperature same as or higher than sea 

 temperature. 



Air temperature lower than sea temperature. 



