INDIANAPOLIS — Meteorologists talk about dew point often in the summer months. Maybe you’ve noticed it usually comes up when describing how humid it is outside.

But what does dew point mean, exactly?

The definition is the temperature to which the air most be cooled to become saturated, which would allow dew to form. More simply, it’s a measure of moisture in the air.

The higher the dew point number, the more humid it feels.

Dew point chart: Comfortable vs. humid

measuring humidity dew point

When we talk about dew point temperatures in the 50s, we’re in a rather dry air mass. It feels pretty good outside, and you’re probably not noticing the humidity.

At the 60-degree mark, the air starts to get heavier and stickier. At 65 degrees, you’re most likely feeling uncomfortable.

When dew point temperatures rise as high as the 70s — which does happen in Indiana, although it’s not common — that’s more typical of a tropical atmosphere. The air is heavy and muggy, and you’re probably sweaty.

What in the Weather?

Check back weekly for “What in the Weather?” questions and answers. Next we’ll explain relative humidity — and why it’s not the best measure of how it feels outside.

Is there something you want to know about the weather, in Indiana or otherwise? Submit your question here for The Weather Authority team.