With a polar air mass from Canada settling over the region this weekend, local residents are being warned to brace for the coldest temperatures so far this winter on Saturday and Sunday, and take steps to avoid frostbite.   

“This is an aberration in this winter season, which has had average temperatures of five degrees above normal,” Gary Lessor, meteorologist and assistant director with The Weather Center at Western Connecticut State University in Danbury, said Friday. “This weekend will be by far the coldest we’ve had this winter.”

Saturday’s high temperatures will only reach into the teens in southeastern Connecticut, and likely will plummet below zero at night, Lessor said.  

On Sunday, high temperatures will barely climb out of the single digits during the day before dropping even lower at night.

With winds of up to 15 mph expected, the wind chill temperatures will feel like 25 below zero on the shoreline and 35 below in interior towns most of Saturday and Sunday, Lessor said.

In such extreme cold, Lessor said, exposed skin can become frostbitten in just 10 minutes.

Dr. Oliver Mayorga, chairman of the Emergency Department at Lawrence + Memorial Hospital in New London, advised people to stay indoors “unless they absolutely need to be out.”

People should dress in layers when outdoors, avoid getting wet and change into dry clothes as soon as possible if they do get wet, Mayorga said.

He recommended wearing mittens instead of gloves, drinking lots of fluids and consuming ample calories to give the body enough fuel to ward off the effects of hypothermia.

“And don’t drink to excess,” he said. “A lot of cold-related injuries happen when people are drinking.”

During an extreme cold snap a couple of years ago, some local residents came to the emergency room with frostbitten fingers after getting drunk and falling in the snow.

Some had to have fingers amputated as a result, Mayorga said.

Signs of frostbite include skin turning white, loss of sensation, clumsiness, confusion and blistering fingers.

Anyone concerned that they may have frostbite should go to the emergency department, Mayorga said, where staff know the proper procedures for rewarming.

The coming bitter temperatures prompted Gov. Dannel P. Malloy to activate the state’s Severe Cold Weather Protocol on Thursday. It will stay in effect through 10 a.m. Monday.

Under the protocol, the state departments of Emergency Services and Public Protection, social services, mental health and addiction and housing will coordinate with homeless shelters to ensure that people are out of the elements this weekend.

Catherine Zall, executive director of the New London Homeless Hospitality Center, said that both the shelter on State Pier Road and Covenant Shelter on Jay Street are prepared to house anyone who needs it this weekend.

“Everybody can come in,” she said.

Additional staff will be on hand this weekend to manage any additional demand, she said.

In addition to protecting themselves against frostbite, local residents are also being advised to make sure water pipes don’t freeze and to use proper ventilation with heating devices.

Norwich Public Utilities advised customers to open their faucets to allow a drip of water to be released through the cold snap, to never use their ovens to heat their homes, to keep portable space heaters at least three feet from furniture, drapes and other flammable objects and to use carbon monoxide and smoke detectors in their homes, among other steps.

“While we want all our customers to stay safe and warm this weekend, we are also reminding folks to keep an eye out for their neighbors, particularly older members of our community, in the very cold days ahead,” John Bilda, general manager of NPU, said in a news release. “As always, we are ready to respond to any emergency, 24 hours a day, every day of the year.”

j.benson@theday.com

Twitter: @BensonJudy

Cold weather tips from the state Department of Public Health:

Dress in layers.

Cover your skin.

If you have to go outside, wear a hat, scarf or knit face mask to cover your face and mouth.

Make sure sleeves are snug at the wrist.

Wear mittens.

Wear water-resistant coat and boots.

Avoid alcohol and caffeinated beverages. These make your body lose heat more quickly. Drink hot sweetened beverages instead.

Do outside work during the warmest part of the day.

Take frequent breaks from the cold.

Know signs of frostbite and hypothermia and get medical treatment right away if you experience symptoms.

Make sure infants stay warm. Infants under one year old should not sleep in cold bedrooms because they lose body heat more easily and are unable to shiver to keep themselves warm. Keep them properly clothed and indoors in warm temperatures.

Check on elderly neighbors and family members. People over the age of 65 often are less active and have lower metabolisms, making them lose body heat more quickly. Make sure that the temperature in their home is adequate enough to keep them warm.

For information, visit: http://www.ct.gov/dph/cwp/view.asp?a=3115&q=472542.