By Jason Allen

FORT WORTH (CBSDFW.COM) – With a holiday shopping season shaped by shortages and supply chain constraints, waiting until the last minute to buy or send a gift this year may be too late.

This is the last weekend to shop and still have packages make it in time for Christmas using standard shipping methods.

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Tuesday, December 14th, is the last average day to order from most online retailers and still have packages arrive on time.

Wednesday, December 15th is the deadline at FedEx and the U.S. Post Office to use standard ground shipping.

UPS tells customers to check its website for deadlines on ground shipping, but says Dec. 21st is when you’ll have to start using air options to get packages on time.

Even that may not be a guarantee though this year according to Nathan Hutson, a professor at the University of North Texas who studies ports, freight and logistics. When there were backups in ports, a shortage of trucks and full warehouses, air freight started to be used more frequently.

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“A lot of the cargo is carried in the belly of aircraft, and so whenever you see shortages, cancellations of flights, that also impacts it,” he said. “Or just the fact there’s still not as many planes flying back and forth.”

Surveys show shoppers expected and maybe even planned for delays this year. Deloitte Insights found 63-percent of North Texas shoppers were starting their shopping early this year.

The USPS said it started planning for the season in early 2021, after seeing nearly a 50-percent climb in packages sent in 2020.

That preparation may be enough to offset the crunch of a last minute rush, but Hutson says its been difficult for consumers to adjust their behavior, unsure of all the changes in supplies and prices.

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“Everything points to it being not a total catastrophe,” he said. “It’s just going to be the Christmas rush, and Christmas related shortages which always occur will just be more apparent than they would in a normal year.”