to London, England, and this is a live look folks.

to London, England, and this is a live look folks. Millions of people under a toxic air alert because of thick fog. You see it here on the live cam. Let's bring in Fox Weather correspondent Katie Byrne. Questions swirling about what's produced this fog and while we can talk atmospherically Katie about what happens, you don't get a lot of wind at the surface and it's bound to you know, fog up or condense if we get those temperatures to drop and reach the dew point. But other factors that are perhaps the reason we're seeing this, the fact that it's dangerous too. Yeah, there's a couple different things going on here but what's really standing out to me is the fact that this has been going on since the weekend. People have been struggling to see just a few feet in front of them in parts of England. So we've seen multiple massive pileups because of this dense fog that's blanketing the region and now a new issue that we're dealing with is the actual air that people are breathing in. So you mentioned London is now under a high pollution alert today and the weather is a big part of the problem. If you take a look at the scene in West London Sunday night, one driver said he couldn't see more than three feet in front of him. He ended up abandoning his car and this was right near London's Heathrow Airport. Everyone was doing two miles an hour. The fireworks of course, crazy fog in South Ruislip. Look at this. It's not even focusing on my camera now. Crazy. It's really wild to see this. These are the conditions on another major road too in Northwest England. Headlights barely cutting through the fog. London's mayor has issued its fourth high pollution alert of the year because of this and the problem is a stubborn area of high pressure. There's very little wind to move the air around, so pollution is building up close to the ground and officials are saying, you heard from that driver kind of tee us up for this, that recent fireworks from Diwali and smoke from an annual British celebration called Bonfire Night have made things worse there. So that's added even more smoke and those fine particles to the air. The mayor is urging people to limit their time outside, exposure, even their time in their cars, especially kids, older adults and people with heart or lung conditions. But the good news is that this weather pattern is expected to change. We're expecting to see some colder air across the UK that that'll help disperse some of that air around and just bring some much needed relief to people who've been dealing with this since really Saturday. So it's been a number of days and we're not expecting to see a big improvement until Thursday or Friday guys. Yeah, which is the remarkable thing Katie to your point that you had mentioned at the beginning. You know, when we look at fog here in the United States, yeah, you can have mornings where you have it in in a row, but where it lingers, where where it just stays put is is really tough to achieve unless you're along the immediate coast. Fascinating thing. Thank you for the update. We'll be watching it carefully in England. Katie Byrne for us. Thanks Katie.