Wind Speed Conversions

by Bert Millar

Do you ever get confused by some of the marine jargon that you ear? Port, starboard, weathercock, leacock, heel, righting moment etc. Yes, so do I, and one term I dislike is knot or knots.

You’re sitting on your campsite listening to the marine forecast on your VHF and the guy tells you to expect winds at 20 knots from the SW or 10 knots from the NE. What is a knot? Well, it’s a nautical mile. What’s a nautical mile?

Well, to be honest I don’t know and don’t really care what a knot is. Why can’t they give it to you in kilometres per hour or miles per hour? Although I was weaned on mph, after several decades of metric measurement I’ve finally got a pretty good handle on kilometres per hour.

10 km/h = A fun day on the water, lively seas, no bugs and I can paddle up or downwind without too much problem.

20 km/h = Another good but more challenging day, maybe one metre swells, good surf waves if there is enough fetch and I can still penetrate upwind for a reasonable distance.

30 km/h = Big seas, a strong breeze, need for protected landing and launching spots; still able to penetrate upwind but not for any great distance.

Anyway, for your convenience I’ve found a little Wind Speed Conversion Chart that simplifies that part of the weather info.

Knots Miles Per Hour Kilometres Per Hour
1 1.152 1.85
2 2.303 3.70
3 3.445 5.55
4 4.606 7.41
5 5.758 9.26
6 6.909 11.13
7 8.061 12.98
8 9.212 14.83
9 10.364 16.68
10 11.515 18.55


This article appeared in the Spring 2008 issue of QAYAQ.