I remember one trip coming down from Lund to Lions bay. winds were 15 dropping to light at noon then picking back up to 20.
Girlfriend wanted to stop off on thormanby for an hour to visit relatives, and despite knowing that we didn't have time in the weather window I agreed. 1 hour turned into 2 and as we left welcome passage I though this isn't good. Sechelt to Gibsons was 1.5M, 4 second swells, and in a 20ft boat with following seas that's not good. As waves built more and more while heading south I found myself using full throttle (300HP) climbing waves, cutting throttle just before cresting the wave, steering hard to correct as the stern picked up and the bow dug in, darting left or right, then as soon as the bow started to climb it was full throttle to keep the nose up to climb the next wave, and repeat for about 40 minutes.
I think the others in the boat realized it was serious when I turned the music off and said I wanted everyone in lifejackets and the ditch bag being held at all times. it was a scary white knuckled ride the whole way. I very clearly remember looking at green water through the windshield several times. Next time I said we can't stop to visit there was no argument
I think a lot of rough water situations arise from not following the plan, or sticking to the plan when conditions change. And of course, the boat totally changes the definition of rough. Two of my worst were in an open 16' Skookum Sealer [the old Oak Bay and Pedder Bay rental types].
On our first trip out of Telegraph Cove, we didn't understand how different the standing waves were with different wind and tides - or that there were safe routes around them. We had crossed to the Plumpers and Hanson thru 3-4' standing waves, which is noticeable but manageable in that boat. The return trip was during an ebb tide and a 25+ knot westerly - and I found myself in 8-10' standing waves, which threatened to overtake the bow and the stern - but fortunately we came thru dry, except for spray. We wore a lot of rain gear in those days. In future trips, we learned more about routes and timing.
The second one was leaving Bella Bella, heading for our truck and trailer in Bella Coola. The plan was to head for a bay near Ocean Falls for the night - on what theory said should be a dying westerly in the late afternoon. As soon as we nosed out into the main channel, it was clear that the westerly wasn't anywhere near dead yet. 5-6' breaking crap was following us up the channel, and it was already too late to turn back. I spent the next hour stepping forward and back to get the boat out of the trough and then prevent the bow from being buried. When we finally got there, the bay was exactly as charted -- but what I hadn't realized was that the surrounding land was low-lying, and the bay offered no protection. Our next option was another 10 miles up Dean Channel. And even though the channel had turned 90 degrees, the wind followed, so conditions stayed the same as darkness fell. We made it at dusk, quivering, well aware that sticking to the plan had nearly been disastrous.
Change the channel to my first day in the 23 Hourston - running from Nanaimo to Comox in a dying 35 knot SE with 5-7' following seas. It looked terrible. The sportfishing fleet off Qualicum was lurching around as it ran for cover. And I was cruising at 22, wearing shorts and a t-shirt, playing tunes - warm and dry. What a difference a boat makes! These days, we are much more cautious than we need to be.