Would you believe 20 below? Metro-east under wind chill advisory.

Weather forecasters have put the area on an advisory as wind chills were projected to drop between 10 and 20 degrees below zero.

Thursday will mark the 11th day of below-freezing temperatures throughout the area, according to St. Louis National Weather Service meteorologist Mark Britt. The area’s forecast doesn’t call for above-freezing temperatures until Sunday.

“So anytime we put out any type of advisory or warning, we are just saying there is an increased chance that you could get frost bite in a short period of time,” he said. “If you’re going to be outside you need to wear multiple layers of warm clothing, limit your time outdoors, wear a hat and gloves —you need to take extra precautions in these bitterly cold conditions.”

Britt said there is potential for a dusting of snow Thursday night, with a storm system bring a wintery mixture of snow, sleet and freezing rain on Sunday.

“Especially since the ground has been cold, people should pay attention to the forecast and be prepared for hazardous conditions during the latter half of the weekend,” Britt said.

Belleville should see a high of 16 degrees Thursday and a low of 6 degrees that night.

At least eight school districts canceled Thursday classes because of both the cold temperatures forecasted and the boil order posing challenges operating schools.

A boil order was issued Wednesday for a majority of St. Clair County and parts of Monroe County after frigid temperatures broke numerous water mains.

The boil order covered most of the metro-east service area, including Belleville, East St. Louis, Centreville, Brooklyn, Fairmont City, Sauget, Shiloh, Washington Park, Alorton, Cahokia, Swansea, Canteen Township, St. Clair Township, Stookey Township and Smithton Township.

People in those areas should bring their water to a rolling boil for 5 minutes before using water for drinking or cooking. Water is OK for bathing, washing and other common uses, but officials asked residents to hold off on non-essential uses like washing dishes and doing laundry.

Drinking water was still available Wednesday afternoon at stores like Walmart, Schnucks, Shop ’n Save and Target in the metro-east.

However, Ruler Foods in Fairview Heights, the newest grocer in town, ran through most of its supply early Wednesday afternoon.

Officials recommend people call ahead before going to a store to purchase drinking water.

This story was originally published January 4, 2018 at 6:38 AM with the headline "Would you believe 20 below? Metro-east under wind chill advisory.."