I have a 20' Triton Dual Console with a 225 HP. I don't go out in anything over 1-3'. I have got caught out there in 4's or little better twice and I didn't like it. I watch my forecast but as others have said you have to be by the water, see it, then only you will know the true conditions for the next few minutes! It can and does change in a heartbeat at times.
Earlier this year I was in my friend's 20' Bass Boat. We launched out of Dunkirk,NY (Lake Erie) and went west about 5 miles. We got there within no time with pretty smooth conditions. We fished about 45 minutes and several boats were around us. It started kicking up some, a white cap here and there. We saw a few boats leave and then some more white caps build. 10-15 minutes later we decided we better head back since their were constant white caps. It was a bad sign when we were leaving and no other boats were around us anymore, duh are we stupid or what!?

It was a LONG ride back to the east, the winds were pushing directly at us on the way back in... We stayed dry until we had to turn right into the harbor at Dunkirk. We turned right and had about 200 yds to go to get behind the breaker wall. Within no time 2 waves hit us hard. I couldn't have got any more wet had I jumped in the water, nor could the guy sitting beside me. The bilge pumps came on instantly pumping water. We hurried as much as possible traversing the waves and luckily made it behind the breaker wall. If we would have caught one more wave we'd have been in big trouble. Waves that are 4-5' and coming over the side of the boat are no fun at all. That day was no fun, we spent the rest of the day shivering and fishing behind the breaker wall. I really hope I don't ever see that again but I learned a few things. I'm telling you this story just so you know how quickly things change and what can happen if you don't listen and watch the weather.
As everyone else says, watch the weather, look for the first sign of building waves, whitecaps, etc. Winds out of the south are usually better since it typically means the water nearshore will have smaller waves. Take your time getting back in, it will be a drier ride and safer.
My favorite place to fish is Presque Isle bay just for that reason. It seldom gets rough enough (it can and does though) that I can't fish it and if the main lake is too bad I fish the 3000 acre bay and catch plenty of nice fish.