The temperature on any given summer day may be in the 80s or 90s. So why does it feel so much hotter and oppressive at times? That's the heat index doing its thing. Here's how it works: What is the ...

Relative humidity is not a good way to tell if we have muggy air on the way. Here’s why. The key word in relative humidity is ...

The iTHX-SD transmitter lets users view virtual charts and record temperature, relative humidity and dew point over an Ethernet network or the Internet with no special software—just a Web browser. The ...

Dew point/relative humidity questions come up fairly often and this is a good one. Water vapor in the atmosphere is pretty important for deep-sky observing and photography. The atmosphere can only ...