Offshore fishing is not always sunny skies and a calm ocean. Wind, rain, swells, and many other weather conditions keep the ocean in a constant state of change. And while this can be frustrating to those with small boats and limited chances to fish; the changing ocean conditions are what bring the fish in waves (Yes...pun intended).
Learning to deal with, and fish in, rough weather conditions is hugely important to catching more fish (NOTE never fish offshore beyond the ability of the boat!). This means knowing how a boat handles varying ocean conditions, what the weather will most likely be doing, and being prepared for the weather.
Having good rain gear, deck boots, proper clothes, and all safety gear will make those rough days offshore that much better. And on the plus side...the fish are most likely going to bite better!