Table 106. 



BEAUFORT WEATHER NOTATION. 



Especially intended for the use of mariners, but sometimes used at land stations. The 

 original notation was devised in 1805 by Admiral Sir F. Beaufort; it has since been slightly 

 altered and amplified by British and American meteorologists. TJie following svmbols are 

 used by the marine observers of the U.S. Weather Bureau: — 



Upper Atmosphere: 



b. — Blue sky. 



c. — Cloudy sky. 

 0. — Overcast sky. 



Lower Atmosphere: 



v. — Visibility (exceptionally clear). 



2. — Haze. 

 m. — Mist. 



/. — Fog. 

 Precipitation: 



d. — Drizzling. 



p. — Passing showers. 



r. — Rain. 



s. — Snow. 



h. — Hail. 

 Electric phenomena: 



/. — Lightning. 



t. — Thunder. 

 Wind: 



q. Squally. 



The British Meteorological Office also uses the following: — 



e. — Wet air without rain. 

 g. — ■ Gloom. 



u. — Ugly or threatening appearance of the weather. 

 w. — Dew. 



"The letters b, c, are intended to refer only to the amount of cloud visible, and not to 

 its density, form or other quality. They have gradually come to be regarded as correspond- 

 ing to the following cloud amounts in the scale 0-10: b = o to 3; be or cb = 4 to 6; c = 7 or 8; 

 = g or 10." — Marine Observer's Handbook, Lond., 1915, p. 82. 



U.S. Weather Bureau Observers use a line (light or heavy) under the symbol, British 

 observers a dot or two dots, to indicate great intensity. Thus, U.S., ^heavy rain,£, very heavy 

 rain. British, r, heavy rain; r, very heavy rain. 



Smithsonian Tables. 



236 



