Since the first day of summer is in June, why isn't it the hottest month?  Isn't the sun on its most northerly track on June 21?  Shouldn't North Carolina be getting its most direct sunlight and heat during June?  Let's find out.

Before we begin, I should say that the title is a play on the tagline for NBC's Meet The Press.

First let's find out if the premise of the question is correct.  What is the warmest month in NC?  The following average high temperatures are for Charlotte, NC.

January - 51
February - 56
March - 64
April - 73
May - 80
June - 87
July - 90
August - 88
September - 82
October - 73
November - 63
December - 54

So July is the warmest month; August is second; and June is the third warmest.  Why is that?  On the first day of summer (June 21), the sun is on its most northerly track and providing NC with its most direct sunlight.  Isn't the sun what makes it hot?  More sun equals more hot, right?  Apparently not.

I found a comment online that said:

In a coastal region where the sea works as a reservoir of heat, the warmest part of the summer will be delayed to perhaps August.
In a continental region, away from the sea, the warmest part of the year will be when the sun is the highest in the sky: at the end of June and beginning of July."

OK, so NC is close to the ocean which soaks up heat during June and July when the sun is strongest, making July the hottest month.  So that must mean that a place like Wichita, Kansas, far from the ocean should be warmest in June, right?  Apparently not.  Their average temperatures are:  June (87), July (93), and August (92).  In fact, June in Wichita is an even more distant third than June in Charlotte!  So, now what?

I think another online comment gets it right:

In the Northern Hemisphere, the sun reaches its most northerly point on or about June 21 (Summer Solstice). Logically, that would be the warmest time of the year since the sun's rays are shining most directly down on us. However the earth is still warming up from winter, and the time when incoming heat and outgoing heat radiation are
equal occurs about 5-6 weeks later. That's when the warmest part of the year occurs.

Another way of saying this is that on June 21, the incoming heat from the sun still has a lot of "leftover winter" to warm up, and that heat is soaked up by the earth.  After 5 to 6 weeks, all the winter is burned off, and once again more heat starts escaping the atmosphere than stays within it.  That's why the middle of July is the hottest month in Charlotte and in Wichita!  Now you know... the rest of the story.  Good day!