Amanda Pampuro

DENVER (CN) — Hundreds of thousands of people in Colorado are about to experience the coldest day of their life on Thursday. Winter is bringing the Mile High City its coldest day in more than three decades — during which more than 1 million newcomers moved to the Denver metro area.

Since 1990, the population of Colorado has nearly doubled, from 3.2 million to 5.8 million as of 2020, with a majority of people moving from Texas, California and Florida, per Stacker’s analysis of U.S. Census data.

The National Weather Service is forecasting temperature swings of more than 70 degrees across the Front Range on Thursday. Starting at a high of 50 degrees on Wednesday, the air temperature is anticipated to plunge down to minus 13 degrees before settling in for a high just 2 degrees Thursday.

Factoring in wind chill, meteorologists warn the weather will feel as cold as 60 degrees below zero across the Eastern Planes each night until Friday. These temperatures can cause frostbite in three to five minutes and put people at risk of hypothermia.

“My son asked if it was going to cold enough to get the pot of boiling water and throw it in the air and watch it all turned to ice before hits the ground,” said Jeff Weber, an atmospheric scientist at the National Center for Atmospheric Research. “Yes, it will be.”

Weber said this kind of polar plunge occurs every 30 years or so, meaning it’s rare but not unheard of. Born and raised in Colorado, Weber has experienced several cold snaps throughout his life and looks forward to skiing when the temperature warms enough Friday or Saturday.

The cold snap comes courtesy of northwestern Canada, where a clockwise-rotating anticyclone is building up pressure. The extremely high pressure, measuring 1070 millibars, generates momentum, pushing frigid arctic air south across the U.S., gifting winter weather down Colorado’s Front Range, across Texas and out to the Gulf of Mexico.

The Eastern Planes of Colorado will see the lowest temperatures in the state, while the Rocky Mountains can expect snow just before Christmas. Winter storm warnings have been issued from Aspen to Vail and Estes Park.

“Generally speaking with the colder temperatures, the drier the snow, the fluffier, the more champagney it will be,” Weber explained.

Although Steamboat Ski Resort trademarked the phrase “Champagne Powder,” many snow lovers liken the Centennial State's dry snow to bubbly wine.

While 10 inches of snow typically contain an inch of water, Thursday’s snow may be twice as dry, with a snow water equivalent measuring 20:1.

“Other than trying to mentally prepare for this cold, there's tons of physical ways to prepare,” said Caitlyn Mensch, a meteorologist at the National Weather Service Boulder. “The main thing is to avoid being outside if you can, especially during the coldest times of the day.”

Residents are reminded to keep pipes along external walls dripping to prevent them from freezing. Pets and livestock should be brought indoors.

People experiencing homelessness are particularly vulnerable to extreme weather.

“Even a warm sleeping bag is not going to be enough in these situations that we're about to experience. Anything minus zero, those are life threatening conditions,” said Stephen Hinkel, public relations managers at Denver Rescue Mission. The Christian organization operates three shelters in the city, with a combined maximum capacity of 1,000 under emergency conditions.

“Our staff will go around the general radius of our downtown location and tell people that there are options for them, that they don't have to stay on the street,” Hinkel said. In addition to providing hundreds of hot meals, he anticipates serving gallons of coffee through the cold snap.

“I think the coffee will be in high demand, and we will do our best to supply said coffee to those who will have cold hands,” he said.

In anticipation of the extreme weather, Denver Mayor Michael Hancock announced the opening of the Denver Coliseum to serve as a 24-hour warming center and Colorado Governor Jared Polis activated 100 members of the National Guard “to support extreme cold weather operations.”

“Colorado is about to face extreme weather and cold temperatures and the guard is ready to assist local communities to help keep people safe during this extreme-cold weather snap,” Polis said in a statement.

The state Supreme Court and Court of Appeals will be closed Thursday in anticipation of the cold, along with several district courts around the state.

In addition to a new daily temperature record, the National Weather Service may write in a new record for lowest wind chill in Denver. Since it started keeping track in 1975, wind chill has never dropped below minus 45 degrees in the city.

Denver's last sub-zero high was in 2014. The area hasn't seen temperatures lower than 20 degrees below zero since 1990. In December, Denver's average high temperature is 44 degrees, with an average low of 18.

The coldest temperature ever recorded in Denver was minus 29 degrees on Jan. 9, 1875. Temperatures of 25 degrees below zero were recorded in 1876 and four times in the 20th century.