When is it too rough to fish safely

I haven't ventured out for crabbing yet, and I'm also looking to make my first forays out there in the near future (when work slows down).

As far as wind in general, even in the bay I always pay attention to the forecasted direction relative to my launch. If the wind is blowing me back into my launch I'm a lot more tolerant of it. Similarly, if the swell or tide is running opposite the wind it's going to jack up more, running with it then you are fighting two forces and have to put that into the calculations.

I'm relatively new, so I've been working my comfort level up going further and in more challenging conditions step by step. Like learning how much wind I can deal with in fairly contained conditions. (I also duck hunt, so wind is part of it) Anytime you are out in nature there can be risk, but I try to be smart about leaping into moments of forced consciousness expansion unnecessarily.

crash and Cabeza de Martillo have good answers, but you asked about conditions for crabbing and those may be entirely different since you'll be bobbing up-and-down and trying to raise heavy pots.

I enjoyed reading the answers to this question.
 "He that kayaks with wise persons will become wise".