Tonight, the Arctic slam snarling travel and triggering headaches during the rush home from the holidays.

Tens of millions of us under winter alerts tonight, with dangerous conditions already on the roads and in the sky.

Thousands of flights already delayed as another storm barrels straight for the northeast.

We're tracking it all.

Breaking tonight, two helicopters

crashing into each other, one of them spinning out of control. At least one person dead.

The crumpled wreckage on the ground. The NTSB now investigating. We're live at the scene.

The president's peace push, the high stakes meeting behind closed doors with Ukraine's leader today,

pledging a deal will get done and what to expect from a separate second summit set for tomorrow

with Israel's leader. Chaos in California after a gas leak shut down a major highway, forcing people

nearby to shelter in place. What's behind the new push, more than a decade later,

to finally try to track down that Malaysian Airlines flight

that vanished without a trace,

along with 239 people on board.

The truly wild saga for one man,

whose crawl space is now home to this 500-pound bear that won't leave.

It's a nightmare.

It's like a carnival house of world.

The noises, the smells, and why wildlife officials haven't been able to get it out.

The future of food that looks, spreads, even apparently tastes like butter, why this carbon copy could mean a big boost

to the environment. And there's good news tonight about our hopes and dreams for 2026 hidden in all

that confetti set to rain down on Times Square. This is NBC Nightly News with Hallie Jackson.

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