When I was in London towards the end of last year, I got pretty lucky in for the most part avoiding the downpours the city is famous for. And when I did get caught out in the rain, you luckily only had to wait around five minutes or some small amount of time before the clouds would break and you could continue going about your day. I say that because there’s a similar phenomenon that savvy travelers are pretty familiar with at this point — the constant deals on cheap flights from carriers who continually offer fare sales throughout the year. Such that, if you miss one, you generally don’t have to wait long before the next one comes around.

Now is one of those moments. Frontier Airlines is running one of its regular sales, this one a spring travel sale with flights as much as a whopping 90% off. The catch, as always, is that you don’t have long to act: You’ve got to book your flight by Monday, February 10.

Head to Frontier’s deals page to check out which markets are able to take advantage of this offer.

Your travel has to fall somewhere between April 21 and June 10, and this deal is valid for nonstop round-trip travel between select markets. As part of the promotion, a 90% discount is valid for travel on Tuesdays and Wednesdays to select markets, while a 10% discount applies daily. There are also blackout dates to be aware of, and they include May 20 through May 26 to all markets.

Additional blackout dates include travel to and from New Orleans between April 21 and May 5, as well as travel to and from and Louisville, Kentucky, between May 1 and May 5. Use the promo code “SPRING” when you’re booking. The discount applies to base fare only, not to fees or taxes, and you have to book your travel by 11:59 p.m. Eastern Time on February 10.

Andy is a reporter in Memphis who also contributes to outlets like Fast Company and The Guardian. When he’s not writing about technology, he can be found hunched protectively over his burgeoning collection of vinyl, as well as nursing his Whovianism and bingeing on a variety of TV shows you probably don’t like.