August 2024 Observations and Discussion

67 with 81% humidity though I am not feeling the humidity much right now. Absolutely a beautiful morning. I am having a coffee and studying the signs of fall now showing up: a slight yellowing of the leaves on the Linden/Alder tree (always a reliable indicator of a coming fall), a slight curling and yellowing of the Hosta leaves (sad!), and now just a tinge of red in the poison ivy (I was not looking hard enough yesterday or the painters did it last night). All in just a couple of days. It is a pleasure to be outside.

dkodgis wrote:67 with 81% humidity though I am not feeling the humidity much right now. Absolutely a beautiful morning. I am having a coffee and studying the signs of fall now showing up: a slight yellowing of the leaves on the Linden/Alder tree (always a reliable indicator of a coming fall), a slight curling and yellowing of the Hosta leaves (sad!), and now just a tinge of red in the poison ivy (I was not looking hard enough yesterday or the painters did it last night). All in just a couple of days. It is a pleasure to be outside.

Dew point is the key to how it feels Damian.  Humidity level is a misleading measure of how it feels.  Dew points this am were upper 50's to low 60's depending on exactly where you are; although they will be creeping up throughout the day.  By early tomorrow am the DP area wide should be low 70's.  Id be willing to bet tomorrow am's coffee will feel much more "humid" compared to this am.

Here is a good way to think about humidity relative to the dew point.  The lower the DP the less water the air can hold; the higher the DP the more water the air can hold.  Looked at another way: Picture two buckets.  These will represent dew point.  First one is a 5 gallon bucket; second is a 10 gallon bucket.  the 5 gallon bucket represents a dew point of 62* and the 10 gallon bucket represents a DP of 72*.  Obv the 10 gallon bucket can hold more water than the 5 gallon bucket.  How does this apply to humidity?

If I add 4.5 gallons to the 5 gallon bucket you could say the bucket is 90% full, or this would be saying the humidity level is at 90% its capacity to hold water.  If I added 5 gallons to the 5 gallon bucket it would be 100% humidity.  Follow so far.  Now lets say we add 6.5 gallons to the 10 gallon bucket.  As a percentage the 10 gallon bucket is only 65% full, aka 65% humidity; however there is 2 more gallons in the larger bucket (when the DP is higher) when compared to the 5 gallon bucket.  For you and I it would "feel" more humid if we woke up to the 10 gallon bucket 65% full,(DP 72*) when compared to the 5 gallon bucket 90% full(DP 62*) because there is more water in 10 gallon bucket, despite the fact that the 5 gallong bucket is closer to full capacity as a percentage.

To summarize: the percentage of the bucket being full is the humidity level.  The size of the bucket is the dew point.  And as the bucket fills approaching capacity(aka humidity level approaching 100%), means the air temperature is approaching the dew point temperature.  

Fog in the summer is an example of the DP and Air temp meeting.  Lets say the DP is 72 and the air temp drops to 70 overnight in a valley.  This is the 10 gallon bucket receiving more than 10 gallons of water.  Once full the extra water spills out, or moisture comes out of the air in the form of fog.  As soon as the sun comes up and heats the air temp back to above 72* the fog "burns off" and disappears.  The reality is the humidity drops to less than 100%.

Damian you may have know all of this already and/or had no desire to get a lesson in dew point this am.  If this is the case my apologies my friend.  lol  Truth is I am bored and figured Id activate my mind a little to explain, what I think, is actually a pretty cool aspect of the weather.

Not sure if any of you have seen this commercial on TV yet, but my son sent this to me a few weeks back saying dad this is you btw. LOL I have to admit I laughed pretty hard watching.  I think the commercial is totally appropriate for many of us in here, and in particular seconds 24-26 apply to the discussion above.   Enjoy the holiday weekend folks.

No I did not know and I appreciate the info. The bucket analogy did it for me

Scott, that was a phenomenal explanation!! The only thing I will add is that the temperature can’t drop below the dew point, at least on a macrophysical scale. On a microphysical scale, though, that gets a bit murkier as you start getting into the realm of super-saturation.

Happy Labor Day to all!

64 degrees, clear, calm winds.Saw some frost warnings in Western and Northern NY State.Three nights in the 40's coming here.Beautiful week of weather ahead.

Just a beautiful Sep 1 day.

Moderator, we need a new Sept thread.

74 with a bright sun with no clouds in the sky. The sun is making it hot. There is a stiff wind. 15 mph with occasional gusts to 22 mph. I could not ask for a better day except for a kegger party at someone's house