Throughout playing Forsaken Shores, I have seen that volcanoes have many signs of an eruption, and even out at sea, there is enough time to get out of their range (Marked by small sparks falling)
But just imagine, if you are at a volcano, no earthquake, no sounds, no nothing, just a volcano that erupts violently with no warning and in a violent manner like in the video below.
I can't say I agree. There are plenty of gimmicky "warnings" like the earthquakes, but they arent certain of an eruption, the only surefire way you know its coming is from seeing smoke, and if you arent very near or on your ship by then you can forget it. Waiting out an eruption and proceeding onto an island right after also rarely seems to lot you enough time before another sudden and abrupt eruption to do anything. It feels more like a diceroll on whether you'll be granted time to finish a voyage rather than that of a challenge based on choices and planning.
Volcano Eruption in Papua New Guinea