3 - Indicator figure, direction of swell waves group
dw1dw1 - Direction from which first swell waves are coming in tens of degrees
e.g.
Code True direction
00 no swell waves
18 180°
36 360°
99 confuded, direction indeterminate
dw2dw2 - Direction from which second swell waves are coming in tens of degrees
e.g.
Code True direction
08 080°
18 180°
36 360°
- Supplementary and auxiliary
ships do not report this group