JetBlue and Southwest Airlines are offering big discounts on winter and spring flights this week but travelers will have to act fast to capitalize.

JetBlue’s two-day “The Big Winter Sale” features one-way flights from as low as $44 but only runs through 11:59 p.m. ET Wednesday. The discounted Blue Basic or Blue seats are valid for travel between January 21 and March 31, 2020. However, blackout dates apply February 18-19.

Sample fares include Atlanta to Fort Lauderdale for under $60 one-way and New York City (JFK) to Los Angeles for less than $150 one-way.