Today is the first day of spring, or the vernal equinox, but it doesn’t feel that way for a lot of the country. It’s still pretty cold, and it will remain chilly for a while. Here’s why.
When you think of spring, you probably think of warm, sunny days, picnics in the park, and the occasional spring shower. And it’s reasonable to expect that because we’re getting more daylight each day and the sun is warming things up. But for most of the U.S., spring actually tends to be a few degrees colder than fall. That’s right, those wicked autumn winds that blow the leaves off trees are no match for springtime’s winter hangover. As Justin Grieser at Washington Post points out, spring is usually somewhere from two to six degrees colder than the fall season. And, depending on what part of the country you’re in, the spring equinox could be as much as 15 to 30 degrees colder than the fall equinox in September.
But why? Isn’t there more sunlight in the spring? Yes, but warming up the planet takes time. Enter “seasonal temperature lag.” More of the sun’s energy is hitting this part of the Earth come spring, sure, but most of it is being used up to heat the ground and large bodies of water first. Once that happens, everything else catches up and the overall temperature finally increases. So, it’s spring now, and you can be excited about the notion of it, but it won’t stop feeling like winter for a little while longer.