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Old 10-02-2019, 11:24 AM
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kenobi 65 is offline
Corellian Nerfherder
Join Date: May 2000
Location: Brookfield, IL
Posts: 16,608
Originally Posted by GMANCANADA View Post
@Kenobi 65 - I did read the post a couple times and I'm still at a loss as to what from a practical POV I (a regular Joe Lunchbucket - not a photographer who shoots at sunrise or a pilot etc.) would do differently knowing the dew point is 7C versus 13C on a given morning or over the course of a day. What do you and the others that understand this do differently because of it?
One big example: if I see that the dew point is high (say, 60F or above), or that it's going to be increasing into that level during the day, I might close the windows of my house and turn on the air conditioner before I leave for work in the morning, knowing that, even if it feels fairly comfortable at 7am when I leave the house, it's going to feel uncomfortable by the time I get home.

And, that "uncomfortable" is a function of both the heat *and* the humidity. If it's going to be 80F, but with a low dew point, I don't feel like I need the air conditioner -- open windows, and maybe a fan running, are enough for me to be comfortable. But, that same air temperature, with a higher dew point, tells me that I *will* be uncomfortable. (And, if it's going to be 90F, I'm turning on the A/C, regardless of the dew point. )

Also, as Anglachel notes, relative humdity is a fairly useless measure for those sorts of decisions, as the exact same amount of humidity (that is, the same dew point) will have a lower relative humidity measure during the day, simply because the air has warmed up.

Last edited by kenobi 65; 10-02-2019 at 11:24 AM.