If nothing else is certain in life, you know the sun is. It will always rise and set and it will always get higher in the sky after the Winter Solstice in December.
Here are the sun angles throughout the year.
You may already know that they’re the lowest in the Winter and the highest in the Summer. You can see on the left side of the graphic the angle the sun is on a given month.
Notice that April sun angles are the exact same as our August sun angles. They’re at a 51-degree angle in the sky.
If the sun and its angles are how we heat up then why isn’t it as hot as August right now?
Could it be the day length?
Let’s compare the middle of each month. The day length on April 15th is 12 hours and 46 minutes. On August 15th it’s 13 hours and 3 minutes. An extra 17 minutes of daylight wouldn’t mean an extra almost 30 degrees in daytime heating.
The answer lies in the cumulative effects of longer days and higher sun angles. The Earth heats and cools very slowly. In April, we’re coming out of shorter days and lower sun angles so that means less heating each day.
In August, we’ve already had several months of high sun angles and very long days. All of that adds up to a much warmer atmosphere.
So the most intense sun happens in June but the hottest temperatures of the year are typically in July and August. Just like turning a burner on, there’s a lag in the heating. The same can be said for the coldest time of the year which is typically in January and February… after the lowest sun angles and shortest days in December.