Stressed about the end of summer? Here’s how to deal with September.

If January is the Monday of the calendar year, then summer is clearly its weekend—June is Friday, July is Saturday, and August is a inactive, delicious, restless Sunday. Which is why so many of us are currently in the grips of “September terrors.”

Those familiar with the concept of Sunday Scares will recognize this feeling. (And yes, the analogy suggests we should call them August Scares, but alliteration trumps symmetry here.) It’s the combination of fear, regret, and anticipation that comes with the end of a collective pause and the beginning of a frantic and demanding time.

Part of that can be blamed on our collective fantasy of summer. Whether or not you’re still tied to a school schedule, the months without school are inevitably associated with pleasure, freedom, and spontaneity. “We underestimate how much our scripts and narratives about the season actually affect us,” says Kari Leibowitz, a research psychologist whose upcoming book How To Winter explores our preconceptions about the seasons and how to reframe them. “Summer is ice cream and the beach. Responsibilities and real life are for September.”

August, perhaps more than any other month, is a time when we allow ourselves to relax. Emails don’t have to be answered as quickly; even text messages to friends can be answered at a leisurely pace.

“There are a lot of things that get put off in the summer,” said Will deFries, whose popular Sunday Scaries Instagram Account has been posting memes about the phenomenon since 2014. “There are a lot of ‘I’ll worry about it later.’” But by the end of August, later is a long way off, and we can start to feel the pressure of the busy season. (Mr. deFries said his account sees a spike in engagement around Labor Day weekend — a sign that the “fears” are particularly acute this time of year.)

You might also feel like you wasted your summer—not sipping Negronis on a pebbly Italian beach or admiring enough of the lush hydrangeas—and now you regret it. August can be really tough, said Amelia Aldao, a Novel York-based psychologist who specializes in cognitive behavioral therapy. “You expect your summer or vacation to be great, and then it’s not. There’s often a mismatch of expectations, which can be a trigger for anxiety.”

If you find yourself trapped in a state of low mood and panic, a good first step is to figure out exactly what’s bothering you. Is it the impending stress of school or work? Is it because you’ve taken a vacation and won’t have another one for a long time? Or is it because you love all the activities of summer but won’t be able to enjoy them for months? The remedies for each misery are different.

If you’re feeling overwhelmed by upcoming tasks, create a plan to get them done. But instead of a to-do list, try a “to-do matrix,” Dr. Aldao suggested. Label the x-axis as “urgent” and “less urgent,” and the y-axis as “significant” and “less significant,” and then plan your tasks in the quadrants accordingly. Seeing where your worries lie can support ease your anxiety. You may realize that some things can be done right away (like signing that form your school keeps nagging you about), but you’ll also have a better idea of ​​what you need to do as soon as Labor Day ends—and what can wait until October.

You could also try “microdosing” on a few September tasks this week, said Christian Waugh, a psychology professor at Wake Forest University who studies positive coping mechanisms. Tardy transitions are always easier than quick ones, he said. He also recommended ditching the “good-bad dichotomy” of summer fun versus September chores. If you have to buy school supplies, for example, don’t treat that trip as the official (and unhappy) end of summer. Instead, plan to buy notebooks in the morning and hit the pool in the afternoon.

This can also support you plan some fun things to do in the fall. Research shows Dr. Waugh found that people who can anticipate positive things — even diminutive things like a date with a friend or a recipe they want to try — are more resilient to stressors.

“Everyone on the Internet is fascinated with fall right now. It’s soup season, it’s spooky season, it’s pumpkin spice season. It’s something to look forward to,” Dr. Leibowitz said.

And finally, don’t fight it. Transitions are inherently stressful, and you may need to accept that this time of year will always be fraught with tension. “Switching from one activity to another is always harder than just doing what you’ve been doing,” says Ayelet Fishbach, a professor of behavioral science at the University of Chicago Booth School of Business who studies motivation. Starting a fresh project — or in this case, a fresh season — is the hardest part, but once you get going, it gets easier.

“People often think Monday is easier than Sunday,” Dr. Fishbach said. “On Sunday, you were afraid of Monday. On Monday, you just do it.”