As pilots we plan carefully to cater for forecast weather in consideration of the capabilities of our aircraft, so as to arrive safe and sound, even if sometimes late.
As pilots we try to avoid significant weather, go around it or delay for it to pass through or recede. An aircraft has the speed to manuvre around weather and generally a better view of what is happening around it, it also takes quite significant weather to actually knock an aircraft out of the sky. Most weather related accidents are because a pilot lacked the experience or skill to negotiate the weather they were in, ie bad decisions and loss of control. In a boat you have much less capability to go around weather and make quick on the fly decisions to avoid it, the decision needs to be more often not to leave port then to try to run the gauntlet of large waves, high winds and squals. Once on the open ocean there are numerous scenarios where the boat can fail from under you, or weather back you into a corner you cant recover from, compounded by bad decisions or lack of experience. Although many experienced and skilled mariners have come to grief because the weather doesn't comply. First the weather will knock out your ability to steer and combat it, then it batters you until you run aground or just sink.