— -- What are the worst days to fly? There are several specific dates every year when airline tickets jump in price. Much of it has to do with seasonal pricing and the dates vary from year to year.
Here are the ones I think you should watch out for in 2016 as you make vacation plans.
Note: The data I drew on for my analysis is my own and includes airfare prices for 15 major cities across the United States for seven-day trips.
Worst Days to Fly - Domestic Trips
These are the dates to avoid for flight departures.
March 17: The cheap winter season is over and -- sorry, St. Patrick -- but March 17 is the date of this year's spring price jump. If you're looking for a getaway from the snow, be sure to begin your trip by March 16.
May 17: Prices jump again as the more expensive pre-summer season gets underway. If you plan on gifting your college grad with a trip, here's hoping commencement is earlier in the month so he or she can begin a trip by May 16.
June 10: The final jump of summer, which is (of course!) timed to when most of us want to start vacation and that's the point: Airlines know when we want to fly and price accordingly. Vacations during the most popular weeks and months of summer are traditionally the priciest, airfare-wise. If you can start your vacation a little early, take off June 9 instead of the day after.
July 31: This is the last day of higher weekday prices (although this date is actually a Sunday); in other words, if you fly Aug. 1, you'll find many weekday fares are lower than the week before. So wait until August to start your trip. Or even later.
Aug. 22: This is the last day of expensive overall higher summer pricing. As of Aug. 23, fares drop to the lower weekday levels mentioned in the preceding paragraph. If possible, delay summer vacation until Aug. 23 or beyond to reap more savings.
Wednesday, Nov. 23 and Sunday, Nov. 27: These dates that oh-so-neatly bracket Thanksgiving are traditionally the most expensive days of the year to fly because they are so popular. If you can avoid flying even one, you could save big.
Worst Days to Fly - Trans-Atlantic Trips
The dates to avoid for trips to Europe.
March 17: Again, fares to Europe jump slightly on this date, which marks the end of the winter season. It's not a deal-breaker by any means, but if you can start a late winter trip by March 16, your fare will likely drop.
May 17: This date inaugurates the start of the pricey international summer season and includes another fare hike for flights to Europe. If you can start your trip even a day early (May 16), you will likely save some money.
Aug. 22: If you planned to begin that trip to London or Rome on this day, hold off another 24 hours. On Aug. 23, fares will drop as the airlines begin their fall season. They call it fall because the kids are back in school and demand for flights drops. Waiting brings other benefits like shorter lines at attractions, just-as-good weather, but, most of all, cheaper flights.
Don't book too early. For domestic flights, purchase tickets between 90 and 30 days before departure. For international travel, you can start five months ahead but try to have your purchase wrapped up 45 days before departure.
The opinions expressed in this article are those of Rick Seaney and do not reflect those of ABC News.