Dry air has arrived

Posted at 10:40 AM, Dec 11, 2018

COLORADO – Dry air has taken over this week and was really felt around the region on Monday. The “dew point” is a measure of moisture in the air. Dew points on Monday were in the single digits and the negatives during the day. Any dew point below 30 or so is considered very dry, with the dryness only increasing as dew points fall further.

Across the nation, a dew point between 40 and 60 is usually considered “comfortable”. As dew points increase from 60, the humidity becomes more uncomfortable. Dew points often reach the 70’s during sticky southern summers. That’s basically the opposite of our dry issue.

So how do our low dew points affect things? Well, the most obvious issue is dry skin and lips. Chapstick and lotion get extra use when the air gets so dry. Dry air can also cause thirst. If we’re breathing very dry air, our body needs more water to balance it out.

In terms of our weather, dry air cools and heats differently than air with more moisture. Dry air allows temperatures to cool very quickly at night, especially with clear skies in place. During the day, that dry air responds to sunlight by warming very efficiently so temperatures increase quickly. For example, on Monday we started the morning in the single digits and teens, but we were already approaching 50° by noon!

We have “dry air” pretty frequently here in Colorado, but dew points in the negatives aren’t as common. The dry air might make things a little uncomfortable at times, but it does usually bring us some nice daytime temperatures.