For route planning, you need either Jimmy Cornell's World Sailing Routes, or the British Admiralty book. These show, by month, the winds, direction, force, etc. I don't know of a web site that has such comprehensive information.
I am away from my computer and so cannot access my links to the NOAA weather sites and the tropical cyclone sites. However, a quick Google search will provide you with many links. NOAA, http://www.nhc.noaa.gov/
for Atlantic and Eastern Pacific hurricanes, for example.