One week and still no sign of Nancy Guthrie.

I'm Carmen Roberts Fox News.

But President Trump tells reporters he feels the FBI may be close to definitive answers about what happened to the 84-year-old mother of NBC's Savannah Guthrie.

We have some clues, I think, that are very strong.

And I think we could have some answers coming up fairly soon.

Fox's Jonathan Hunt has more from Tucson, Arizona, after another message showed up yesterday.

A flurry of activity yesterday at Nancy Guthrie's home. We saw, for instance, agents on top of a building at that

home, not the main part of the building, but

it's off to the side, an agent removing what looked to our drone camera operator as if it was

some sort of security camera. Clearly, there is a major search still underway for all of these

clues. They're going through evidence as they gather it.

They're also looking across the Tucson area for any surveillance evidence.

And bitter cold is gripping much of the eastern half of the country and could be life-threatening

in the northeast and New England. And this is people across the country get ready for

tomorrow's Super Bowl,

including people in Boston, where wind chills may dip to 25 below tonight.

We're going to have a party right here at Commercial Wharf, so we're going to stay home. And that woman in Boston, Fox Weather's, Brandy Campbell, is also there.

This isn't the first snow of the winter.

Boston has seen 24% above average snow to date

with just over 34 inches to fall this season. And after this snow, they're also going to have to

deal with the coldest temperatures of the season. Temperatures could dip into the single digits

overnight going into the big game day this Sunday. This type of weather causes havoc out on the roads.

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