As an unprecedented winter storm looms over vast regions of the United States, authorities are urging the public to heed warnings regarding the severe weather conditions that could pose significant dangers.

Exposure to the extreme cold without adequate protection can quickly result in frostbite, escalating to hypothermia, a condition far more dangerous than simply feeling chilled. Hypothermia occurs when the body’s core temperature drops below 95 degrees Fahrenheit, causing the body to lose heat faster than it can generate it.

This condition signifies a critical failure in the body’s ability to regulate its temperature, a system that typically keeps us functioning within a narrow range of safe temperatures.

Hypothermia can set in within just 30 minutes of exposure to the frigid temperatures anticipated this weekend. During this time, the body prioritizes preserving vital organs such as the heart, lungs, and brain, at the expense of less critical areas.

With the Arctic blast set to sweep across the East and Midwest, understanding the serious implications of this physiological response could be crucial for survival.

More than 200 million Americans are under a winter storm advisory. Come Sunday, when the storm is at its worst, forecasters predict that over half the people in the continental US will be dealing with some form of wintry mess, such as snow, sleet or freezing rain, all at once. 

Temperatures Friday night into Saturday morning will hit the single digits on the East Coast while the upper Midwest will see temperatures fall far below zero, to as cold as minus 39 degrees.

Panic buying has left store shelves completely empty as millions of Americans fret about an impending inability to drive through what could be up to 18 inches of snow in some parts of the US. Southern states, which typically do not see this extreme weather, are bracing for widespread power outages and school closures. 

Inadequate gear can cause frostbite within minutes, opening the door to hypothermia, a true medical emergency. Snowfall from earlier this year is pictured above in Illinois

Dr Alina Mitina, an emergency room physician at Hackensack University Medical Center in New Jersey, previously told the Daily Mail: ‘For a properly dressed and healthy adult, exposure should be limited as much as possible. Taking breaks in a warm place every 20 to 30 minutes is good practice.

‘For vulnerable individuals, or if you are not adequately dressed, you could be in danger in as little as 10 to 15 minutes.’

Hypothermia sets in as wind and wet air suck the heat from your skin and your nervous system makes a calculation to sacrifice blood flow to the limbs to save the heart and brain.

Blood vessels in your hands and feet clamp down in a process called vasoconstriction, turning them cold and pale. This causes uncontrollable shivering, a manifestation of the muscles burning through fuel in a desperate bid to generate warmth.

This is mild hypothermia, when the body’s core temperature falls to 90 to 95 degrees. 

You are still alert, but the clock is ticking. Your speech slurs. You fumble with zippers. You might feel a bizarre urge to urinate as the body reduces blood volume to ease the strain of the blood vessels constricting. 

Even if you recover from mild hypothermia, the severe, prolonged vasoconstriction can itself cause tissue damage in the extremities, setting the stage for frostbite and potential amputation. 

The map scales the impact of the winter weather, taking into account snowfall, accumulated snow on rooftops, ice accumulation, the potential for a flash freeze and blowing snow

This map shows where heavy snow is most likely during the winter storm through Monday. Areas in the purple and pink have the highest chances of seeing the most snow accumulation

Temperatures over the weekend will be frigid across the south and up the east coast, posing the risk of widespread freezing on roads

This is the critical window to get warm. If you don’t, you spiral into the next, deadly phase.

When your core temperature drops into the high to mid-80s, the shivering stops, a catastrophic sign, as it means your body’s furnace has run out of gas.

Confusion sets in. You become lethargic and may make the fatal decision known as ‘paradoxical undressing,’ or, stripping off clothes because your malfunctioning brain actually – and incorrectly – thinks your body is burning up.

This is when the real damage begins and immediate medical attention is necessary to avoid catastrophic complications or potential death. 

This is severe hypothermia, below 82 degrees. Your heart slows to a dangerous crawl. The risk of it descending into a deadly, chaotic rhythm called ventricular fibrillation skyrockets.

Your brain, starved of warm, oxygenated blood, begins to shut down. You slip into a coma. Breathing becomes shallow, then sporadic.

The brain, severely deprived of blood flow and oxygen due to the extreme blood vessel constriction, slips into a coma. Breathing becomes very slow, shallow and irregular.

At this point, toxic lactic acid floods your bloodstream as your tissues become starved of oxygen, poisoning your organs from within. Meanwhile, the heart becomes increasingly unstable, eventually slowing to a dangerously sluggish state known as bradycardia.

The slide into unconsciousness is accelerated when you are wearing wet clothing, which increases heat loss 25-fold. Exhaustion, meanwhile, is emptying the body’s energy reserves.

Temperatures Friday night into Saturday morning (above) will hit the single digits on the East Coast while the upper Midwest will see temperatures fall far below zero

More than 200 million Americans are under winter storm advisories. Over half the continental US population will be battling snow, sleet, or freezing rain simultaneously (file photo)

When your body temperature sinks to 75 degrees or lower, the body appears clinically dead. All signs of life – pulse, reflexes, breathing – may be undetectable due to their extreme slowness and weakness.

Yet, a crucial protective mechanism, the diving reflex, may come into play. This reflex, triggered by cold on the face and a lack of breathing, slows the heart to a near-standstill and drastically reduces blood flow to non-vital tissues, profoundly lowering the body’s metabolic rate and conserving as much remaining energy as possible.

When metabolism plummets, the brain’s demand for oxygen drops, triggering a protective state called suspended animation that allows it to survive without oxygen for much longer than would be possible at normal body temperature.

Resuscitation efforts must continue while actively rewarming a hypothermic patient, as complete neurological recovery is possible even after prolonged cardiac arrest in a profoundly hypothermic state.

Hypothermia kills between 1,000 and over 3,000 Americans each year. CDC data shows 1,024 such deaths in 2023 and up to 3,500 in 2022.