Arctic air flowing into the southern United States Friday

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Arctic air surging south in the United States

A blast of Arctic air is moving across the United States, with some of the coldest temperatures expected Friday morning. A strong cold front has been moving across the lower 48 of the United States the past few days, with Canadian high pressure following along in its wake. As this high pressure dives south, the Arctic air also dives south. It will bring frigid conditions across the United States, particularly the southern and eastern U.S.

Freezing temperatures … in Florida?

Forecasters expect the Arctic air to impact many areas across the south and east, including as far south as south-central Florida! The Miami National Weather Service Office issued a Freeze Warning for Friday morning. The warning is mainly for inland areas where temperatures are expected to fall below freezing.

While south Florida can experience cold temperatures relative to its normal morning temperatures – which are in the low 50s (10 degrees Celsius) this time of year – it has been a while since chilly weather has prompted a warning. In fact, the last time the Miami Weather Service issued a Freeze Warning was in January 2022. (In October 2024, the National Weather Service consolidated and simplified its cold weather information. Prior to this, a Freeze Warning was called a Hard Freeze Warning. You can find more information on the simplified weather information from the NWS here.)

While a Freeze Warning does warn about freezing temperatures, it is mainly used for the agricultural industry. Freeze Watches and Warnings are meant to let growers and food producers – particularly those with sensitive plants (including Florida citrus) – know that it’s time to protect their crops from cold temperatures that could damage or kill them.

Temps and wind chills for Florida

For human protection, the National Weather Service issues Cold Weather Advisories and Extreme Cold Watches and Warnings. The NWS issues Cold Weather Advisories when dangerously cold conditions are forecast. Those advisories have been issued for most of south Florida for Friday morning. Wind chill values (what it will feel like when the wind is factored into the air temperature) should be as low as 26-30 degrees Fahrenheit (-3 to -1 degrees Celsius).

For some across North America, this is a typical winter day, but it’s important to remember that impacts from temperature are relative. In a place like south Florida where temperatures are warmer, the criteria for “dangerous” cold are very different from those to the north. It is always important to take every advisory issued by your National Weather Service office seriously.

Staying safe in extreme cold

If extreme cold is forecast for your location, make sure you are protecting yourself and your loved ones. As soon as you know extreme cold is in the forecast, if you are able, adjust the amount of time you will spend outside. The coldest part of the day is typically the morning, so avoid being outside at that time. If you have to be outside, bundle up! Dress in layers and cover any exposed areas to the outside air with hats and gloves.

Wind chill is an important factor

Know the risk from the wind. Wind chill is how much colder it feels due to wind. It’s based on how much heat is lost from any exposed skin from the wind. The stronger the wind, the more heat it draws away from your body, which cools your skin temperature, and then your internal body temperature. As your body temperature decreases, your risk of hypothermia increases.

Hypothermia is a serious health condition. It happens when your body temperature drops below 95 degrees Fahrenheit (35 degrees Celsius). Warning signs that someone is suffering from hypothermia are shivering, confusion, difficulty speaking, stiff muscles and drowsiness. And, in serious cases, it can result in a lack of consciousness.

If you suspect someone has hypothermia and they have passed out, immediately call 911! Even if that person hasn’t passed out, call for medical assistance and start to warm them up from the center outward. You can do this by lying next to them, and covering both yourself and the other person with thick blankets to slowly raise their body temperature. The warmer you are, the more body heat you can transfer until help arrives.

Arctic air particularly hard on the vulnerable

Cold impacts everyone differently, but some groups are especially vulnerable to the risks of cold weather. These include the very young, including newborns who can’t regulate their own body heat yet, as well as the elderly. People with chronic illnesses are also more susceptible to cold-related health risks.

In addition, people who spend most of their time outside are at risk. This includes outdoor workers, the unhoused community and people who don’t have a regular place to stay. Underserved or impoverished communities who may not be able to afford to run their heat as often are also at risk from the cold. So make sure you are checking on your neighbors and community members so they can stay safe during an Arctic outbreak.

Stay up to date with your local forecast by visiting your local weather service office website. In the top left, enter your location for your up-to-date forecast.

Bottom line: Arctic air is diving south across the United States, impacting millions of people, even as far south as south Florida! Another cold blast is on the way for early next week.

Read more: U.S. winter weather outlook and how La Niña will factor in

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