Rain on your wedding day is said to be good luck, but how much does the trick? Danya Skolkin and Josh Tillis didn’t pause to consider the ratio of precipitation to luck when skies turned ominous in the days just before their wedding last fall.

But on Aug. 25, as Ms. Skolkin and Mr. Tillis were finalizing the details of their Sept. 3 wedding in downtown Houston, Hurricane Harvey made landfall, ripping into that city and reaching its peak just before the college sweethearts and their more than 300 guests were about to celebrate.

At first they crossed their fingers, hoping the wedding would go on. But with six days to go and meteorologists in slickers deployed across the city issuing warnings about the devastation to come, Ms. Skolkin and Mr. Tillis, both 28, made the decision to postpone.