I know that breaking up is hard to do, especially when you've been going steady for so long. But enough is enough. It's time to split up with the "relative humidity." The love affair has gone on too long. Time to move on to something better, like the "dew point."

Yes, I hate to tell you this, but relative humidity is pretty much a useless term. Oh sure, it sounds good during the weather report. After all, it's been in weather reports as long as we can remember. Dew point sounds too scientific. It sounds like one of those terms invented by the media just to make a big deal out of weather. But I'm telling you right now, build a bridge and get over it. Dew point (DP) is happening. Relative humidity (RH) is out the door.

Here's the deal with RH: it is relative to the air temperature. Warm air has a higher capacity to hold moisture than cold air. An RH of 50% means the air is holding half of its capacity of water vapor. But at 90 degrees, 50% of capacity is a lot more moisture than the air at 60 degrees.

Dew point is the temperature at which moisture will begin to condense. If we were in a room with a temperature of 75 degrees and a dew point of 55 degrees, than we would have to cool the air in the room down to 55 degrees before we would begin to see moisture condensing. Water would start to collect on surfaces in the room like tables and windows. When the air temperature equals the dew point, the relative humidity is 100% and we say that the air is saturated.

Since dew point is not relative to the air temperature, it is a good measure of the actual amount of moisture in the air. It is also a good comfort measure. Dew points less than 55 degrees indicate comfortable air, not sticky or clammy. When the dew point gets above 60 degrees, the air starts to feel humid. Above 65 degrees and many people are uncomfortable. A DP over 70 degrees and the outdoors becomes a living steam room.

Here is an example of why RH doesn't tell the whole story. If the air temperature is 90 degrees and the dew point is 71 degrees, the relative humidity is 53%. An RH in that range doesn't sound bad. Only about half of the local atmosphere is full of water vapor. But remember that 90-degree air can hold a lot of moisture, so 53% is steamy. The dew point of 71 will tell you that. If you cool that air down to 76 degrees and don't add or subtract any moisture, the DP will remain at 71 degrees and the RH soars to 85%. The higher RH indicates conditions are much more humid, but in reality the moisture content of the air is the same.

I know old habits are hard to break. We love our RH. When I first came to Milwaukee in 1982, I took the RH out of the current conditions when I displayed them on the air, but I did include the DP. The calls and letters came in fast and furious: "Put that humidity back on the TV." Nearly 20 years later and I still include it on my weather reports. But remember that the DP tells the real story. Breaking up is hard to do.

Watch Vince Condella on Fox 6 Sunday through Thursday at 5, 6 , 9 and 10 p.m. You can see the FOX 6 weather forecast around the clock at www.fox6milwaukee.com