Humidity rising, dewpoints going up, and what that means for the heat index

It has not been very humid lately with comfortably cool air in place across the region. With our winds coming out of the north, northwest, and sometimes east, that means cooler temperatures and less humidity. Why? Well, when the winds are coming out of those directions, they are bringing the air that is in those locations with them. And, those areas (to our north, northwest, northeast, east) typically have cooler, drier air. Therefore, when we get winds out of those areas, they bring cooler and drier air with them. That is why we have been comfortable and dry lately--our winds have been coming out of those directions.

The above situation is usually present when an area of high pressure is either to our west or right over our region. That has been the case this week. However, when the high slides off to the east of our location, which typically happens with high pressure systems, the winds turn to south and southwest because wind flows clockwise around a high pressure system.

If you look above, the point "A" is seeing cooler air (the Stateline region this week), and point "B" is experiencing warmer, more humid air as it is located behind the high pressure system (the Stateline region beginning tomorrow).

Now that we are aware that we will be seeing southwesterly winds and warmer temperatures, let's discuss dew points and humidity...

The dew points will be climbing into the mid to upper 60's and possibly into the 70's through the weekend. Also rising will be the relative humidity values. Those two factors, when combined with hotter temperatures, will make for a "feels like" temperature, or heat index, that reads several degrees warmer than the actual air temperature that a thermometer reads. What does that mean for you? It means the level of discomfort felt when you step outside will be escalating for the remainder of the week and into the weekend.

Temperatures earlier this afternoon were very warm across the Northern Plains and Southern Plains. You can see two distinct areas of dark red and dark pink, which depict the two areas of warmest temperatures. Those pockets of air will continue edging towards the Stateline tonight and will truly arrive by Thursday afternoon with our highs expected to push into the upper 80's. However, take a look at the heat index values to the left. Those values are slightly warmer than the actual temperatures shown above. That is because the temperature your skin feels when you are outside factors in both the temperatures and the humidity outside. And, we will have both higher temperatures and higher humidity values, which will allow our heat indices to possibly push into the low to mid 90's.