What are the variables?

It can vary a little bit depending on factors such as weather fronts moving through the area and whether or not it clouds up or rains...but on an average sunny day, it is usually around 3 PM. The hottest hours of the day are from around 1 PM - 5 PM.

Im not sure about all the variables, but I have my own opinions...

Trees and vegetation are a significant factor, as witnessed by myself on a trip to Idaho last year. The hottest part of the day (summer, late June - early July) in East TN is around 1 to 2pm. On my trip to Boise (Meridian actually), I was surprised to learn the hottest part of the day there was around 5-6pm.

I figured this was due to the lack of trees around, and the fact that the longer duration of sunlight (lack of shade from trees) just made things hotter by the end of the day.

Of course, there is no even comparison between an 80°F, 80% humidity day in TN and a 105°F, 5% humidity day in ID. As my Idahodian finace will attest, its not the heat - its the humidity.

Jonathan

Well we got her nailed down to somewhere between 1-6 pm.  I could have guessed that!  I am looking for something a little more scientific.

I think the answer is that it's subjective to the immediate environment and location. Pressures, warms fronts, cold fronts, humidity, landscape, bodies of water in the vicinity, etc...

To be a little more scientific.

Jonathan

Don't know about the rest of the country but in TEXAS it goes like this

Midnight: Cool
Early Morn: Warm
Mid Morn: Hot
Early Afternoon: Very Hot
Late Afternoon: Surface of the sun HOT
Early Evening: Very Hot
Late Evening: back to Warm

Course in TX we call High 80's a nice day

um, bedtime?

Humidity...like just about anywhere on the East coast in the dead of August...95 during the day w/95% humidity--90 at midnight with 95% humidity.  After that most of my life, I sure do appreciate the cool, low humidity nights here in ID.  

According to our weather station here at work, the hottest part of the day for the past week has benn the hour from 13:00 to 14:00.  It has averaged 97.6 for that hour for the past week.  This is down in LA (Lower Alabama)

I think 3:00 PM is commonly touted as the hottest part of the day in these parts. We get the marine layer too usually after 6:00 PM. Today, for instance, it was 109 where I live, but by the late PM, it was down to 78 thanks to the marine layer coming in from SF Bay.

Hell, 20 minutes west of where I live it can be 30 degree colder. No wonder why those coastal homes cost a small fortune.

If you want year-round fog and cold weather, visit Daly City, CA. I don't think that place ever sees direct sunlight.

According to Steve Stucker, our local weatherman, the sun's UV rays are at their worst between 10 am and 2 pm.  I don't know how scientific that is, but at least he's a meteorologist.  Might count for something?

Reviewing the last week's temperature charts for the area close to Dallas the hottest hour of the day is 5 to 6pm.  But it's pretty much a plateau from 4 till 7pm.

Dallas is of course an urban heat island.  Even with a breeze the heat from the city rises and forms an inversion layer that expands out over the surrounding counties and raises their temperature as well.  The inversion layer contains air that is hotter than surface conditions.  So you're basically living in a broiler with the sun and the inversion.

go to [url]www.weatherunderground.com[/url] and do a search for your zip.  Then do historical conditions on the date pulldown and you will get a chart.

Well.... lets see...

It is brighter during the day (provided there are no real dark thunderclouds) than at night (unless the moon is out and full and reflecting off of the snow)...
So that means that the crickets make more noise during the late afternoon and by counting the instances of noise produced by the crickets and averaging that by counting said crickets and coming up with a determined factor you should have developed a good perspiration effort that you finally decided that it must be hot just about anytime it is .. and there is no hotter time than when you are thinking it must be hot...

Therefore it must be hottest when you are thinking about it...

If it seems to be hot ... just watch a movie like Cliffhanger ... you will cool off ..

So in summary I would say that heat is all in your head ... and it really is cold ...

Remember the horse that froze to death in the the heat wave in Kansas.... he was in a cornfield and the corn growing in the field started popping ... pretty soon the field was filled with freshly popped pop-corn. The horse seeing this was shocked and assuming it was snow .. froze to death ... that is how hot it was ...

Ted...

The hottest time of the day is exactly 0.5 seconds before the first cold beer. This varies from day to day.

In the year I have lived in TX so far I have found that we only have 2 weather all day.

1) Hot and Humid all day
2) Cold and Sleathing all day