Crosswind component
I was told that if you take the difference between wind & runway, and imagine it on a watch face, then it will tell you how much of the wind is crosswind, i.e.
runway 20
Wind 230\10
230-200 = 30
30mins on the watch face is half, so that's 10* 1/2 = 5kts crosswind
Let's say,
runway 18
Wind 195\05
195-180 = 15
15mins on the watch face is a quarter, so that's just over 1 kt crosswind.
Although, the floor in this, as far as I can see, is for significant crosswind. I.e.
runway 09
Wind 180/10
180-090 = 90 degrees (therefore 100% crosswind)
But you can't put 90 degrees on the watch face. I guess you work on the assumption > 60 degrees is 100% crosswind