I was just wondering how many out there use the Seabreeze site to check wind speed. I took a screenshot of today's prediction - by 2.30pm I had only recorded a 21kt gust as the highest, where SB indicated 28kt and rising. Now at 3.50pm it feels like it's dropping off (gusting 18kts or so), not getting stronger as predicted on the chart.
I've been using SB for years to check wind for sailboarding and that's been fine, but if if one was to rely on it for regular yachting- just how accurate is it

All the various 3rd party weather sites pull data from various official weather sites. It will depend on the various weather models those official sites use.

That said, some 3rd party sites make available local updated actual weather based on participating local uploading there personal station data..... I don't know for sure, but I have a hazy recollection that Seabreeze does this.
But mostly a forecast is is a forecast until it can be measured as actual. And when the BoM puts a 40% margin on its forescast, the difference between 21 and 28kts is within 40%... Just