And it's still not guaranteed. Weather, considered a force majeure event (which also includes anything beyond an airline's control from strikes to terrorism), is governed by all sorts of arcane rules. Check out any airline's 'contract of carriage' for fascinating details about the ways your airline works and you will find surprises.
Speaking of surprises, American pulled one off recently but maybe they felt they had to. The carrier waived change fees and doled out refunds to unhappy flyers during its long kerfuffle with pilots and those thousands of delayed and canceled flights.
American is now saying "we're sorry" with extra miles for everyone, and since management and its pilots have come to a tentative contract agreement, I do not believe you have any worries about booking with them for the holidays. You may even score a free trip out of it.
Getting Your Money Back
Airlines say they'll post refunds anywhere from seven to ten business days. My personal experience is that you have to wait a couple of billing cycles before it shows up. Don't spend that refund too quickly.
And in the meantime, if you have doubts about your ability to make a flight consider a refundable ticket or insurance. Or gear yourself up for battle. The opinions expressed by Rick Seaney are his alone and not those of ABC News.