Record temperatures brought record numbers of visitors to Brookfield Zoo last weekend and on Monday’s Presidents Day holiday, along with massive traffic jams and long lines to buy entry tickets.

On Saturday, Feb. 18 as the mercury hit 70 degrees, 22,863 people walked through the turnstiles at Brookfield Zoo – a record number for any day in February in the zoo’s 83-year history. And then on Sunday, Feb. 19, the zoo set another attendance record with 27,531 visitors.

“This is the busiest February in the zoo’s history,” said Sondra Katzen, director of public relations for the Chicago Zoological Society, which operates Brookfield Zoo.

The crowds were not just unusual for a weekend in winter – combined attendance on Feb. 18 and 19, 2016 was about 5,000 people – it would have been a big crowd in the peak of summer, according to Katzen, when daily weekend crowds average around 15,000 to 20,000 visitors.

An added attraction for visitors was that zoo admission is free on Saturday and Sundays in February. The zoo drops its admission prices several days per week during February in anticipation of small crowds. That thinking also leads to low staffing levels, making an unexpected crush of visitors a real handful for employees who are working.

“We ask people to be patient,” Katzen said, “because we’re not fully staffed yet.”

And while there was no free admission Monday, the crowds kept coming, lured by a school holiday and temperatures again approaching 70 degrees. By the end of the day on Feb. 20, another 21,371 visitors had walked through the gates at the zoo.

As the weekend dawned, the Chicago Zoological Society posted messages on Brookfield Zoo’s website and Facebook page warning visitors to expect big crowds and to “plan ahead and arrive early.”

But by early on Saturday and, in particular, on Sunday, traffic backups were mounting and Brookfield police were redirecting eastbound traffic on 31st Street to southbound Prairie Avenue in order to alleviate a traffic jam that stretched all the way west to Maple Avenue. Northbound traffic on Prairie Avenue backed up all the way to Jackson Avenue, according to Brookfield Police Officer Daniel McCarthy.

“We were sending people south to Washington Avenue and Ogden and then back around, any way to ease up the flow of traffic [on eastbound 31st Street],” McCarthy said. “Sunday was much worse than Saturday. It was backed up but not so bad.”

But Sunday, he said, “was just insane.”

Construction on 31st Street east of Prairie Avenue narrowed eastbound traffic to just one lane, making the situation worse. Police received calls of near collisions as vehicles jockeyed for position approaching the zoo entrances, and there was at least one report of motorists getting out their cars and exchanging words.

On Monday, Feb. 20 there were anecdotal reports that some visitors were avoiding the zoo parking lots and were parking in forest preserve lots at McCormick Woods and Zoo Woods along First Avenue as well as the Brookfield Woods parking lot on 31st Street near the entrance to the Salt Creek Trail and then walking along both sides of First Avenue and 31st Street to the zoo’s north entrance.

Once inside, visitors packed the zoo’s malls and crowded around outdoor exhibits to glimpse animals, such as the giraffes at Habitat Africa, which don’t usually get to stretch their legs in the sunshine until April.