Living in the house that his wife was killed in is becoming increasingly detrimental to Mr. Laird's mental health - even if it was in tip-top shape (which it isn't).
They could blend in to the populace seeking shelter and help, they could commandeer a much need boat to leave the island for good, or any number of scenarios could unfold that allow these convicts to escape justice.
Make no mistake, the 2017 hurricane season is one of the worst so far, and it's not over until November 30th. With roughly 3 months to go - we may see quite a few bad storms before the year is up.