You can see current wind speed here:
https://www.ventusky.com/
You can tap on wind and move the cursor around different locations. It is fed by many personal weather stations. You can also shift the timeline at the bottom to see a forecast. However remember what Yogi said about predictions.
At weather underground you can see a 10 day forecast including wind.
https://www.wunderground.com/forecas...a/43.61,-71.46
Keeping in mind that wind is hard to predict the exception being presidential debates.
The NOAA app on my phone shows the current wind speed and direction at the Laconia airport.
As for the Broads in your boat I would stick to the 5 MPH wind range while you are gaining experience.