Temps hit an 'all-time low' on this day 33 years ago
Leading up to today, January of 2018 has been the fourth coldest January on record. Our records go back to 1938, so that's saying something!
Still, the temperatures we have seen this month couldn't hold a candle to what we saw on January 21st, 1985. That is when we saw our coldest temperature on record in the Tri-Cities region.
Temperatures plummeted to a bone-chilling -21°F at the Tri-Cities Airport that morning. (The coldest I've observed here in my four years at WCYB was -13°F in 2014.) In both cases, a few things had to come together in order for this chilling recipe to take shape. The first thing, as you might as well have figured on your own, is this: an Arctic airmass.
Digging through archives, I was able to find the upper level air pattern on the morning of January 21, 1985. If you look at Tennessee and Virginia, there's a huge dip in the air pattern. This is what we call a trough, and usually signifies colder air intruding the area.
With Arctic air, you also tend to have very dry air. Drier air allows more room for the temperature to drop at night. More moisture and condensation would lead to the opposite effect - warming.
The last key ingredient, though, was the snow that was on the ground.
How would snow cover impact our air temperature?
Snow is a great emittor of infrared radiation. Once that infrared radition is emitted, our surface temperatures drop off big time under a clear sky. In summation, our record cold on this day 33 years ago was due to a combination of cold and dry Arctic air, along with a fresh snowpack.
Other temperature readings from that day are posted below. These readings were obtained on the National Weather Service website.
Please note that if your town is not posted below, it's not because we don't care. We looked for towns like Clintwood, Marion, etc. and could not find the date.
If YOU have reports from that day, please feel free to send them to my Facebook page.