barb

The name given to each of the small oblique lines attached to the wind-speed arrows drawn on synoptic maps, indicating wind speed. The barbs are drawn on the rear left or right side of the arrow, depending on which terrestrial hemisphere (north or south) is concerned. Each full barb equals 10 knots. Shorter dashes are also drawn to represent 5 knots (half barb). When winds are very intense, such as those blowing in jet streams, pennants are drawn to symbolize 50 knots; this avoids the arrows containing an excessive number of barbs, making them easier to read.