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WCATMCR DIAGRAM 

 February I930. 



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Figure 11.— February weather diagram. Inner figures show day of the month; the next band out 

 contains the record of the atmospheric pressure; the next outer one indicates the degree of visibility 

 (black areas for visibility of less than 2 sea miles and cross-hatched areas for visibilities of between 

 2 and 4 miles); the outer margin shows the average direction and force of wind per 12-hour periods, 

 midnight to noon and noon to midnight. Wind directions are toward the small circle in each case. 

 Arrow indicates true north 



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