all hoping for a swift reversal in U.S. migration restrictions.

Among them, Beatriz Tenorio from Peru, traveling with her husband and their five-month-old baby who they swaddled in layers of clothing - chilled but happy to be on the move, she said.

The U.S. Supreme Court ruled this week that restrictions known as Title 42 could stay in place temporarily.

Implemented under former President Donald Trump at the beginning of the health crisis, Title 42 gave border officials the ability to rapidly expel migrants to Mexico without a chance to seek U.S. asylum.

A federal judge last month ruled that Title 42 was unlawful in response to a lawsuit originally brought by asylum-seeking migrants represented by the American Civil Liberties Union, and set the restrictions to be lifted on December 21.

But a group of 19 states with Republican attorneys general sought to overturn that decision and took their request to the conservative-leaning Supreme Court.

Now many migrants along the border are spending Christmas weekend outside in what Mexico's weather service called a "mass of arctic air" or in bare-bones shelters, with temperatures hovering near freezing.

Without clarity on when the restrictions will be lifted, some officials worry their cities could be overwhelmed if more migrants turn up.