PASADENA (CBS) — As residents begin to stake out campsites along the Rose Parade route Friday, Pasadena’s fire chief warned that cold temperatures will pose special danger overnight.

“This year, the big concern is going to be hypothermia,” Chief Dennis Downs told reporters.

Those seriously affected by the extreme cold may seem to be overindulging in New Year’s celebrations.

“It almost looks like they’ve been drinking, but in fact, they have hypothermia,” said Downs, who dubbed the condition “the umbles. They fumble, stumble and mumble,” he said.

Seniors and toddlers should be especially wary, the chief said, but everyone should be prepared to bundle up against the chill with several layers of clothing.

Revelers should keep in mind that there are strict prohibitions against bonfires. Fires along the route are permitted only in barbecues that sit at least one foot off the ground and are set up at least 25 feet away from any building.

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