Heat Wave on The Way!

Baltimore, MD - The computer forecast models we use at ABC2 News continue to show hazy, hot, and humid conditions moving in by the middle of this week.  The forecast right now shows Wednesday and Thursday being the hottest days next week with high temperatures reaching the middle to perhaps upper 90s.  While 90s are fairly common in summer, the humidity will add to the misery of this hot stretch of weather.

What is a Heat Wave?

The debate rages on in terms of exactly what  constitutes  a heatwave .  With the thousands of definitions the National Weather Service puts out, you would figure a heat wave would be one of them.  Surprisingly, that is not the case!  Since different parts of the country see various temperatures vs humidity values, one definition cannot be assigned to categorize the term "Heat Wave".  

The "unofficial" definition of a heat wave is three consecutive days of 90 degrees or better.  Personally, I feel that is not adequate.  Lets say you have three days of 90 degrees with low humidity.  While, the day will be mighty toasty, the heat will be somewhat bearable.  Having said that, take those exact same days and add a ton of humidity.  While the temperature hits the same degree, the "feels like temperature" will add 10-15 degrees to the the temperature causing the potential of deadly effects to the body.  Humidity is the key to heat waves in my opinion which makes them so deadly. 

The problem with high humidity making us feel hotter is not just that we are more uncomfortable, but that we actually are hotter. The result is our bodies compensating this effect by working harder and harder to cool us down. When sweating doesn't work to cool us down and we continue to heat up, overheating results, which causes loss of the water and chemicals that the body needs. Overheating, or more commonly, heat exhaustion, can lead to dehydration and chemical imbalances within the body.

The forecast going into this week is unfortunately going to include high humidity.  So while the initial thought is 94/95 both Wednesday and Thursday, the heat index will range between 100-105.  I could also see our nighttime lows struggling to get out of the 80s making for several uncomfortable sleeping nights.