(Portland, OR) -- Portlanders planning on taking a flight this summer should be prepared for more crowds. Up until now, travel volumes have been below pre-pandemic numbers, but it's changing. Port of Portland officials expect summer travel to peak early this year at Portland International Airport. The single busiest day of the summer is expected to be this Sunday when more than 51-thousand travelers will go through PDX. The airport is under construction, so travelers are advised to arrive early to navigate changes at the airport.