SALT LAKE CITY (ABC4) – Live in Utah and notice some heavy smoke? You are not alone.

While 1,000 tons of hay burned in Utah County early Friday morning, that isn’t the cause of the smoke hitting the Wasatch Front. Here is a side-by-side comparison of Salt Lake City’s skyline from Friday morning. On the left, the skyline before the cold front moved through and on the right, the city after the smoke moved in.

So what’s causing the smoke? It is actually coming from the Dixie Fire, burning in northern California.

Between Thursday night and Friday morning alone, the Dixie Fire grew 110 square miles, according to the Associated Press. The fire is now the largest wildfire currently burning in the U.S.

As of Friday morning, the Dixie Fire has consumed 432,813 acres – it is also expected to grow.

SLIDESHOW: The Dixie Fire burning in California

According to the Associated Press, the Dixie Fire is only 35% contained and is California’s third-largest wildfire in history.

The smoke in Utah was not unexpected – ABC4 meteorologist Cesar Cornejo says winds were expected to shift with a cold front and bring in the smoke.

Because of the smoke, Salt Lake City currently has the worst air quality in the world.

Air quality experts at the Salt Lake County Health Department have offered tips on how to keep the air inside your home in better condition than the air outside.

Watch this time-lapse of Salt Lake City this morning. You can see heavy smoke begin to move in from the right side of the screen.

According to Chief Meteorologist Alana Brophy, we are forecasted to see unhealthy air in Salt Lake County and air deemed “unhealthy for sensitive groups” in counties including Tooele, Davis, Box Elder, Weber, and Utah.

Wildfire smoke contributes to elevated particulate matter and we already have high ozone levels in the summer. A cold front moving across the state brought gusty winds ahead of it with breezy conditions behind it.

Air quality concerns – and possibly this smoke – will be an issue for the next several days.

Salt Lake City Police are reminding the public that there is no need to report this smoke in general unless you see an active fire burning.

The Utah Division of Air Quality is advising Utahns to stay indoors today as much as possible.

“We actually don’t really know when it’s going to get pushed out. We’re thinking probably through the weekend,” the division’s spokesperson, Ashley Sumner, tells ABC4. “We don’t know if it’ll be this past weekend, but we don’t really see anything that is going to push it out until at least Monday.”

Due to Salt Lake Valley’s unique topography, the smoke is trapped below the mountains, not unlike the inversion effect that can create air quality concerns in the winter.

If you have a severe health concern like asthma or a heart condition, Sumner advises you should avoid going outside.

The tiny and harmful air particles in the air right now can become trapped in the bloodstream and lungs, Sumner says. It’s also important to have as few vehicles as possible on the roads as car emissions can exacerbate the issue. Those who are staying inside should do whatever they need to do to make themselves as comfortable as possible, such as changing air filters or running fans.

Sumner says it is important to monitor your body’s signals – if you feel a scratchy throat or burning in your lungs or eyes, it is time to get inside.