As hundreds of wildfires burn across Canada, smoke is traveling south and potentially affecting Americans’ health. Here's why it can be so dangerous.

Wildfires have been raging in Canada, producing a significant amount of smoke that's being blown by winds into the U.S. Will smoke reach Louisiana?

Smoke from massive wildfires burning in Canada has crossed the Atlantic Ocean and is blowing over the UK. Only a little smoke survived the journey, said Georgie Myers with the UKs