If you have to take connecting flights, connect through warmer weather, less snow-storm affected hubs like Atlanta, Dallas, Miami, Phoenix, Charlotte, Houston vs. Chicago, Minneapolis, Denver, Newark.
Consider travel insurance. If there are any seasons that make sense to buy it, it’s during snow storm and hurricane season.
If your flight is canceled and you’re on the outbound portion of your trip, you can request a full refund of the fare paid, even on a non-refundable ticket. There’s no requirement to take a “futile” trip (i.e., you missed the wedding). Google the airline’s contract of carriage for the rules.
Ask to be put on another airline’s flight if it will get you there quicker. Some airlines such as Alaska have provisions for this in their contracts of carriage. Even those that do not often put delayed passengers on their competition’s flights.
If taking a cruise, always plan to get to the port a day ahead of sailing. In winter, I recommend TWO days ahead.
If your flight is canceled, try to get as close to where you’re head as possible if you can’t get all the way there. If your JFK to LA flight is canceled, see if the airline will fly you to Las Vegas, for example. From there you can hop on Southwest or rent a car to LA.