Travelers eyeing spring and summer getaways can save money when booking on Southwest this month. The airline launched a fare sale on Tuesday with one-way fares as low as $49. The sale runs through April 17 at 11:59 p.m. PT and is good for continental U.S. travel between April 29 and Aug. 27. The sale is valid for travel on Mondays, Tuesdays, Wednesdays, and Thursdays from April 29 to June 12 and Tuesdays and Wednesdays from June 13 to Aug. 27. Deals out of Boston’s Logan International Airport include one-way $59 flights to Chicago; $76 flights to Charleston and Fort Lauderdale; $79 flights to Atlanta; $89 flights to Baltimore; $109 flights to Orlando; $111 flights to Charlotte; and more. The fares apply to nonstop service where indicated. If nonstop service is not indicated, the sale applies to single connecting service. Travelers should note that May 26 is a blackout date for continental U.S. travel. The deal is also good for travel between Aug. 17 and Oct. 3 for international travel and trips to Hawaii and San Juan, Puerto Rico. Tickets must be purchased 21 days in advance of the trip and prices include all U.S. and international government taxes and fees. Seats, travel days, and markets are limited.