Weather prediction is just that: prediction. I wouldn't just trust onbe site over another, read a few, maybe take the worst case and base your judgement on that. I'd been out on a f3/4 forecast and it was more like f5 condition. There are many sites for weather forecast, Metcheck, Accuweather, Wind guru,.....
If you want tide table more than 7 days, then I'm afriad you will have to pay for it.
Site like easytide. All/most of the links are in the links page.