BALTIMORE (WJZ) — A Code Blue Alert has been issued for Baltimore as another dose of Arctic air will move into the area over the weekend.

The alert is in effect from Saturday evening through Monday morning. This is the sixth alert for Baltimore this season. The previous alert that ended earlier this week lasted for 14 days.

The National Weather Service said that rain overnight Friday could change to sleet and snow in some areas of northern Maryland. As temperatures dip overnight, a “flash freeze” on untreated surfaces is expected.

“Overnight and early Saturday morning motorists should monitor road conditions closely and exercise caution if sleet and snow begin falling,” the NWS said in a statement.

WJZ’s Bob Turk also warns of potentially dangerous road conditions Saturday morning.

“A quick freeze-up could make roads really treacherous overnight,” he says.

According to Turk, temperatures in some areas of Maryland over the weekend are expected to dip into the single digits with wind chill.

Last winter, 12 people died from hypothermia in Baltimore City, according to the city’s health department. So far this winter, there have been eight hypothermia-related deaths.

“Hypothermia, or low body temperature, can be just as dangerous as extreme heat, and every year, there are Baltimoreans who die due to hypothermia,” Baltimore City Health Commissioner Dr. Leana Wen said in a statement Friday. “Due to predicted dangerously cold temperatures, I encourage residents to stay indoors in heated areas during these periods. Please help those around you who are the most vulnerable to the cold, including children, the elderly, and people with chronic medical illnesses.”

The health commissioner’s office says it can declare a Code Blue Alert when temperatures, including wind chill, are expected to be 13 degrees or below or when other conditions are severe enough to present a substantial threat to the life or health of vulnerable Baltimore citizens.

Code Blue indicates an increased risk for cold injuries or even death for those exposed to low temperatures. Once a Code Blue declaration is made, public messaging activities are undertaken to encourage safety and response partners work to ensure those in need find sheltering. During the Code Blue season, which began Nov. 15, 2017 and lasts until March 15, 2018, city agencies work together to:

  • Distribute meals to at-risk senior citizens;
  • Provide home weatherization services;
  • Help individuals apply for emergency assistance; and
  • Provide additional cold weather education and outreach efforts

Throughout the Code Blue season, The Mayor’s Office of Human Services’ Office of Homeless Services also works with city homeless shelter providers to extend shelter hours and to provide expanded bed capacity.

Cold weather tips for staying healthy:

• Wear multiple layers of loose-fitting clothing.
• Always wear a head covering, like a hat and/or scarf, when outdoors.
• Drink plenty of fluids and avoid alcoholic beverages.
• Protect yourself against falls in icy or snowy conditions.
• Check on those who are the most vulnerable, including children, the elderly and/or chronically ill. For babies, follow the ABCDs of infant safe sleep (see resource guide here).
• Provide appropriate shelter for domestic animals.

Other tips for keeping safe in cold weather:

• Keep space heaters and candles away from flammable materials, such as curtains, furniture and loose clothing.
• Check your smoke detector and carbon monoxide detectors and make sure they are working.
• Do not use prohibited heat or power sources, such as stoves or generators. They may cause fire or carbon monoxide poisoning.
• Do not leave your car running in a closed space such as a garage.

Follow @CBSBaltimore on Twitter and like WJZ-TV | CBS Baltimore on Facebook