Dew Points

The TV weather reports are using the dew points more than the relative humidity to indicate the discomfort level as being more representative of what most of us feel, although the discomfort level varies by location (Miami, where they are used to high humidity, versus Las Vegas, with very low humidity), and even from person-to-person (my wife versus myself).

But, for Philadelphia, in the summer months, the dew point is the best measure of discomfort for most of us, and is:

Dew Point (ºF)      Comfort Level
<55                             Pleasant
56-60                         Comfortable
61-65                          Getting sticky, especially at night
66-70                          Uncomfortable
71-75                           Oppressive
>76                             Miserable

Relative humidity is determined by a ratio of vapor pressures that can be misleading, so says the Federal weather bureau web site, “A temperature of 30º and a dew point of 30º will be a relative humidity of 100%, but a temperature of 80F and a dew point of 60F [calculates as] a relative humidity of 50%.”

But keep in mind, this is only a subjective guide for most of us in Philadelphia, in the summer. You, in a different location, in a different season, may feel differently.

Therefore, bottom line, easy to remember, you want the dew point to be below 60ºF.

About Roger Walck

My reasons for writing this blog are spelled out in the posting of 10/1/2012, Montaigne's Essays. They are probably not what you think.
This entry was posted in Popular culture. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.