The first signs of winter might be a downer for the cold-averse, but the dip in temperature should serve as a signal to start thinking about summer. Not just to dream about warmer weather, but also to get moving on your travel plans. According to experts, winter is the best time to book your summer airfare.

“The advice that I give generally is, when you’re hoping to travel during the peak season, always book during the opposite season,” says Scott Keyes, founder of the airfare deal-finding company Scott’s Cheap Flights. “When you’re opening up your Christmas presents, also be thinking about where you want to travel that coming summer.”

Thanks to the effect of the school-year schedule, summer in the Northern Hemisphere is a peak time to travel around the world. Holding off until the last minute to book a trip in June, July and early August is likely to result in higher fares, because there’s a ton of demand from people bound to venture somewhere during calendar breaks (families, teachers and school faculty). It’s a tale of woe that Keyes sees all the time.

In general, the window for the cheapest flights to pop up is one to three months ahead of time for domestic travel and two to eight months ahead for international travel, he says. This window changes during popular travel times — summer vacation, cherry blossom season in Japan or St. Patrick’s Day in Ireland, for example — so he urges travelers to book even earlier.

“If you’re looking to travel during peak travel periods, I’d actually recommend adding a couple months to those recommendations,” Keyes says, resulting in a window of up to six months ahead for domestic travel and four to 10 months for international travel.

Once you’re getting ready to buy your flight, don’t overthink the day of the week to do it. Contrary to popular belief, there’s no best day to score a deal.

“There is no cheapest time of the week, or day of the year, to book flights. They pop up at random,” Keyes says. “It’s just like trying to predict what’s the cheapest [time] to buy stocks. It doesn’t follow patterns like that.”

The common misconception persists because it was true at one point. When airfare was first being sold online, the airlines would typically publish their fares once a week.

“As a result, if you were one of the first ones to search and book right after they loaded their fares, then you had some of the best chances to get those cheap seats,” he says. “But that just hasn’t been true for years. Nowadays, the difference is so dynamic, it’s changing sometimes by the minute.”

Although there isn’t a best day to book for the cheapest deal, there is a best day to travel on for the cheapest deal: Tuesday. If you have the flexibility in your travel schedule, Keyes recommends picking a flight on Tuesday, Wednesday or Saturday, and avoid Mondays and Fridays, which are most popular for business travel.

Wrangling airfare these days can be a wild ride. Ticket prices can change up to 130 times before the flight actually takes off, making it a difficult market for travelers to interpret. A fare you see one day may be double the price the next, then lower than ever the day after that.

Getting stressed out by the ordeal is natural, but not helpful. Keyes witnesses travelers getting overwhelmed by confusion, putting off their purchase until it’s too late and paying more as a result.

So when Jack Frost comes nipping at your nose, shift mental gears to summer vacation mode and get shopping. Your bank account will thank you.

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