Wind speed indicator

[sagablu]

Hello all,

Recently purchased a Jeanneau 349 and had The chart plotter updated to a Ratmarine Axiom 7. I can see the wind speed and direction on the plotter, all great. The concern I have is the accuracy of the reading and I'm not sure if I am understanding what I should be seeing. Yesterday I was out in Aurora around 20 knots, maybe more. Yep a minute consistently doing better than 6 knots and was hitting more than 7+ often. Great ride! This was with 2 reefs and full jib. The wind speed was indicating an average of 15 knots. There is no way I'm getting up to 7.4 with 15 knots of wind. I I'm not understanding the discrepancy, is the apparent when that much less? The wind was mostly right on the beam. What should I be expecting to see?

Appreciate your help!