Earthsky FAQs
Why isn’t the longest day of the year the hottest day?
Photo Credit: jurvetson
In the northern hemisphere, the hottest weather doesn't come until July and August.
08-14-2008 - Earth
In the northern hemisphere, the June solstice – the day that receives the most sunlight of the year – signals the unofficial start of summer. But the hottest weather doesn’t come until July and August. This is called “the lag of the seasons.”
On northern hemisphere beaches in June, you’ll notice how cold the ocean feels. By August, the water will be warmer – it’ll have needed those extra months to warm up after winter. I
n June, ice and snow still blanket the ground in some places. The sun has to melt the ice – and warm the oceans – before we feel the most sweltering summer heat.