One of the things that makes the heat so dangerous here in Florida is the humidity. The dew point temperature is the temperature at which the air can no longer hold all of its water vapor, and some of the water vapor must condense into liquid water. At 100% relative humidity, the dew point temperature and the air temperature are the same, and clouds or fog can begin to form. While relative humidity is a relative measure of how humid it is, the dew point temperature is an absolute measure of how much water vapor is in the air (how humid it is). In very warm, humid conditions, the dew point temperature can reach 75 to 77 degrees F, but rarely exceeds 80 degrees.
The dewpoint for the afternoon that caused my heatstroke was between 71f and 74f. The temperature for that 4 hour period was between 91f and 94f. That results in a heat index of between 100f and 103f.
High dewpoints are dangerous because it is a limit on how well your sweat can evaporate and cool your body. Heat can build up to dangerous levels.
Combined with that, it was a bright, sunny day with almost no wind. The Navy actually has tables for permissible heat exposure. Under those conditions, Navy regulations say that acclimatized personnel shouldn’t perform heavy work for more than 15 minutes per hour. I far exceeded that for more than 4 continuous hours.
Even worse, I am now 35 years older than I was when I was in the Navy. I am also about 40 pounds heavier. All of that makes my susceptibility to heat stress more pronounced.
As I said, I know better. Let my experience in this case serve as a warning to others as we enter the hot summer months here in the South.
6 Comments
Gregb · May 21, 2025 at 5:44 am
Just happy you caught it in time. Take care of yourself because nobody else will
oldvet50 · May 21, 2025 at 6:45 am
So glad you’re OK now. I have to question drinking nothing but Gatorade to replenish liquids. I’m no medical expert, but it seems it would increase the concentration of electrolytes in your body without plain water to somewhat dilute them (says the guy that used to take salt tablets in high school, military, etc. during outdoor exercise).
Fred in Texas · May 21, 2025 at 7:21 am
Bad news dude, you are now far more susceptible to heat injuries. But you probably already knew that.
I had a heat injury in August 2010. Fortunately I recognized it and self treated it before it got bad. Unfortunately, it took me years to recover.
Be very proactive at prevention in the future; hydration, electrolytes, take breaks, work in the shade, setup a fan… And don’t panic if you think you’re getting symptoms of heat stress. Just manage the situation. It’ll take a few, to several years to overcome the damage. You probably won’t recover all your heat tolerance. But you’ll be functionally alright in time.
Thanks for sharing your story. A lot of people are absolutely clueless about heat injuries. I’m sure you’ve planted seeds of knowledge in somebody’s mind. It might save their @&$ some day.
Doug · May 21, 2025 at 7:37 am
“A bit dry for some” is just fine for me; “comfortable” is getting too wet. Death Valley in summer is fine. It’s why I’ll never live in or visit Florida again.
Different strokes for different folks (pun intended) 🙂
Tsgt Joe · May 21, 2025 at 8:25 am
Your reports are timely. Today we are cleaning out our old trailer in Okeechobee and taking our stuff to our new place. We are snow birds who ,usually, are back in Michigan May through Christmas. I’ll have to see if I can get electricity to the old place and run the air conditioning. Didn’t handle heat well as a young’n, cant handle it at all at 76. We will probably only work 1 1/2- 2 hours. Dont want to use up Florida medical resources.
Tsgt Joe · May 21, 2025 at 8:28 am
Accidentally hit post before I posted my concern about your health and hopes for your full recovery.