I am trying to find out what the arrow symbols mean, in terms of different colours and number of strokes/fleche

Although It is quite easy to find out this information online, Here is a quick overview of wind plots: The direction of the wind is from the line away from the barbs,ie. if the barbs are to the N and the "stem" of the plot points S, then the winds are out of the N.

Each full barb represents 10 Kn, a half barb is 5 Kn, and a filled in triangular "flag" is 50 Kn. So, one barb is 10 knots, 2 1/2 barbs are 25 knots, and a flag with 3 1/2 barbs is 85 knots.


Hope this helps