It may seem impossible to believe, but spring break has already begun — at the Minneapolis-St. Paul International Airport (MSP), that is.

Earlier this week, traffic at the airport started to pick up, and higher-than-average volumes of winter-weary folk are expected there over the next two weeks, according to the Metropolitan Airports Commission (MAC), which owns and operates MSP.

Spring break has long been a busy time at the airport, even though the period is spread over a number of weeks — breaks aren't uniform throughout the state for school districts and postsecondary schools. The Anoka-Hennepin School District, the largest in the state, has next week off, while Minneapolis and St. Paul public schools scheduled the first week of April for the break.

Complicating matters for spring travelers is the NCAA Final Four basketball tournament April 5 to 8, an event expected to draw about 94,000 visitors to the Twin Cities.

"What we're seeing this year, which is the same as the last couple of years, is that the spring break travel period gets longer and longer," said Cliff Van Leuven, the Transportation Security Administration's (TSA) federal security director for Minneapolis. "It hit this week."

Travelers flying from the airport in the early morning and late afternoon may encounter longer security lines, particularly in Terminal 1 (Lindbergh), which is served by Delta Air Lines, MSP's dominant carrier. TSA said it will ramp up staffing to meet demand.

TSA screens 36,000 passengers at MSP on an average day, with a wait time of about eight minutes for most people and two minutes for PreCheck. But between Feb. 28 and March 29, TSA expects to screen about 40,652 passengers daily — an increase of 13 percent.

However, during that monthlong period, 18 days are expected to top the 40,000 mark, including three days that will likely exceed 45,000 passengers. That means the wait to be screened could be up to 25 minutes during busy periods, Van Leuven said, noting the busiest days are Thursday, Friday and Saturday mornings.

Terminal 1 is also undergoing a massive renovation, so space for lines may seem crowded.

"We lost a considerable amount of passenger space for queuing due to the construction," Van Leuven said. "The lines can appear to be daunting."

While TSA is often blamed for long security lines, circumstances unique to MSP can cause lines to swell during certain parts of the day and dissipate at other times.

That is partly because MSP is a hub airport for Delta, which times its arrivals and departures close together, according to MAC spokesman Patrick Hogan. That is done so customers making connections will have time to make their connecting flights without waiting around the airport for long periods of time.

As a result, hub airports are more prone to peaks and valleys at check-in, security and baggage claim, he said. Last year, Delta carried about 72 percent of all passengers at MSP, its second-largest hub, according to the MAC.

For those who want to avoid clogging up security lines, TSA still recommends that travelers arrive two hours before domestic flights' departure times, and 2½ to three hours for international flights.

Because families tend to travel more often during spring break, TSA notes children ages 12 and under may leave on shoes, light jackets and headwear.

TSA offers several ways for passengers to determine whether an item is permitted in carry-on or checked baggage, or not at all. Travelers can use the "Can I Bring?" feature on the myTSA mobile app or visit its website. They may also tweet @AskTSA or message through Facebook Messenger from 7 a.m. to 9 p.m. weekdays and 8 a.m. to 6 p.m. on weekends and holidays.

TSA spokeswoman Lorie Dankers reminds travelers that the same rules apply to Terminal 2 (Humphrey), which serves Sun Country Airlines, Southwest Airlines, JetBlue Airlines, Icelandair and Condor.

"For many years, travelers have thought of Terminal 2 as a sleepy place where you can avoid the throngs of people," Dankers wrote in an e-mail. "This is no longer the case. Terminal 2 gets extremely busy."

Even though spring break is expected to be busy at MSP, the U.S. Travel Association forecasts a national slowdown in travel in coming months due to weakening global economic growth, trade tensions and wavering consumer and business confidence.

Janet Moore • 612-673-7752 • @MooreStrib