Originally Posted by
cncpc
There are some numbers in there that don't quite add up, but not significant to understanding this.
They add up quite nicely. It has been previously posted that the surface winds were 220 deg at 19 to 21 knots. (Bellmullet 220 at 19Kt, Mace Haed at 230 at 21kt), just about right to create the ground speed as calculated.