What Is The Worst Kind Of Heat?

[zachary_amaryllis]

heat that comes out of heated seats in cars.

yeah, that's just what my 300-lb self wants, more heat on my butt etc. while i'm driving.

[Scott5114]

Heated seats are nice when you have leather seats and the car's been sitting outside in the dead of winter for several hours. But once the seat is a comfortable temperature I usually turn it off, even if the rest of me is still cold.

[jgb191]

Here are several examples on a typical August day assuming normal conditions (not a heat wave),

Yuma, AZ:  Temperature of 105 degrees + dew point of 50 degrees = Heat Index of 102 degrees
Waco, TX:  Temperature of 98 degrees + dew point of 72 degrees = Heat Index of 108 degrees
New Orleans, LA:  Temperature of 93 degrees + dew point of 76 degrees = Heat Index of 107 degrees
Key West, FL:  Temperature of 88 degrees + dew point of 82 degrees = Heat Index of 109 degrees
Corpus Christi, TX:  Temperature of 95 degrees + dew point of 79 degrees = Heat Index of 114 degrees

I've noticed that a dew point around 60 degrees is typically the equalizer, where actual air temperature and Heat Index are equal.

[Bruce]

I barely use the heated seats in my car (most often by accident since it's next to where I leave my mask). Should've gone for back cooling, which is way more useful in my climate.

[tolbs17]

Humidity is worse.

[Road Hog]

The highest dew point ever recorded, 95°F (35°C), was recorded at Dhahran, Saudi Arabia, on July 8, 2003. With an air temperature of 108°F (42°C) the heat index was 178°F (81°C).

[Scott5114]

The highest dew point ever recorded, 95°F (35°C), was recorded at Dhahran, Saudi Arabia, on July 8, 2003. With an air temperature of 108°F (42°C) the heat index was 178°F (81°C).

And yet, that's only 68% relative humidity.

Goes to show you how much water hot air can really hold.

[jgb191]

^  Which further illustrates why Relative Humidity isn't indicative of uncomfortableness.  You can have 90% RH on a freezing day and it still feels far more tolerable than a 60% RH on a triple digit temperature.  Even the actual indicator of moisture amount, the Dew Point, if you ask different people from different parts of the world, you will get varying opinions.  Like for a dew point of 70 degrees is very much tolerable for someone like myself who is accustomed to tropical-like climate, yet it will feel like hell for someone from Canada or Europe who will start to feel uncomfortable once the dew point exceeds 60 degrees.

[kkt]

Humidty is much worse than dry heat.  70 degrees and humid feels less comfortable than 110 and dry.