Monday morning’s rain has moved out, and now the frigid air is moving in!
Temperatures will continue to drop into the 40s during the lunch hour before plummeting into the 30s during the evening ride home.
In addition, the northwest wind will continue to gust as high as 35 mph through the course of the day. Combined with the chilly temperatures, “feels like” wind chill values will be in the 30s for much of the afternoon before dropping into 20s around sunset!
By Tuesday morning, temperatures will drop into the mid to upper 20s, leading to a hard freeze for much of Metro Atlanta. A hard freeze is defined as temperatures at or below 28 degrees for an hour or more.
Hard freeze conditions can damage crops, landscaping, and outdoor plants, but these frigid temperatures can also produce possible frozen pipe damage to your home.
Afternoon temperatures will remain frigid this week as the arctic air keeps temperatures 15-20 degrees below average. As a result, daytime highs will barely climb above freezing into the upper 30s to low 40s.
Looking ahead to Friday and Saturday, there is potential that a Gulf Low will bring moisture into Metro Atlanta while the Arctic air is in place.
It is too soon to determine what kind and how much wintry precipitation will fall, however the set up is favorable for freezing rain and sleet to fall in Metro Atlanta, with snowfall in the North Georgia mountains.
Science Behind the Wind Chill
The National Weather Service says the “wind chill is a term used to describe what the air temperature ‘feels like’ to the human skin due to the combination of cold temperatures and winds blowing on exposed skin.”
In fact, research conducted by the NWS as recently as Summer 2001 involved placing human volunteers on treadmills in a chilled wind tunnel and measuring the volunteers’ skin while the individuals walked on the treadmill. Each volunteer was subjected to various temperatures and wind speeds, with the results used to compile the Wind Chill Index that we use today.
The Wind Chill is expressed as a function that is dependent on the air temperature as well as the wind speed, as illustrated in the chart below.
Naturally, we understand that the lower the temperature, the colder it ‘feels like’ outside.
However, 32 degrees with no wind feels substantially “warmer” compared to 32 degrees with a 10 mph wind (the Wind Chill at that point would be in the 20s).
This ‘feels like’ situation is due to the wind blowing body heat away from us, causing our bodies to continuously cool to the point of potential hypothermia.
According to the CDC, hypothermia is defined as abnormally low body temperature caused by prolonged exposure to very cold temperatures. As a result, the body loses heat faster than it is able to produce, which can lead to a potentially dangerous situation as the body shuts down.
When the wind chill values are low, avoid going outside for long periods of time. If you must go outside, dress in many warm layers of clothing -- this will trap the body heat and is more effective than one bulky layer.