What you will not hear in the forecast There are always uncertainties, even over the open sea. Then there are local effects, sea breezes, headlands, straits, gusts, down draughts. David Houghton's book Weather at Sea or Alan Watts Wind and Sailing Boats are both good. Remember the limitations of the phraseology. The Beaufort scale already implies a range of wind, but the weather does not know itself to within one force.
Nothing is certain in the forecast, except for the date.
Best Advice of All Plan for the worst, hope for the best. The worst may not happen .