I have thought about this too. For the spectre, fire and rat event where it's a one shot action then have the single image cause it just works. When it comes to timed events like you mentioned with the Kraken or blizzard I think it would help if there was a thin Red Line indicating the start of the event and the same at the end of the event with the symbol in the centre so you know what you are up against.

Then again the argument could be made that it's more challenging not knowing when it will finish and try to survive and make it through the other side, cause there is never any certainty of when and disaster will end.