DALLAS — The middle part of the week will feel like summer! Temperatures will climb into the mid-90s as southerly winds keep bringing moisture to the area. That means the heat index is back. Some heat index values will be in the 100s this week.
Why does it feel so warm?
High pressure and high humidity!
A ridge of high pressure is centered just to the west of North Texas. This is what is bringing the intense heat to the desert southwest this week. In fact, Las Vegas is likely to see its earliest 110° day on record. For us, the position of the high pressure keeps us under northwest flow which allows systems to move into the area. That is why so much rain has fallen in the past couple of weeks.
The high humidity is here for a couple of reasons: A wet ground and Gulf moisture. The ground is saturated due to the active spring. So far, DFW has recorded 27.42 inches of rain this year, making it the sixth-wettest year to date. This is nearly 10.5 inches above normal. A southerly wind also keep bringing in moisture from the Gulf. The double dose of humid air and a saturated ground keeps humidity a bit higher.
Why does the humidity matter?
Higher humidity makes a difference with the heat index. The heat index is the temperature it feels like outside. The heat index is a temperature that is calculated using actual air temperature and the relative humidity. The higher the humidity, the higher the heat index.
Our bodies natural cool off by sweating. When the air has a lot of moisture (high humidity), the sweat humans produce does not evaporate as fast as it would during a dry day. This slows down how fast our bodies can naturally cool off.
That is why it feels so warm outside. Our bodies are naturally cooling off slower due to the higher humidity along with the higher temperatures.
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