Say Hello To The Spring Equinox
Spring will begin in the wee hours of Thursday morning this week. If you think you’ve heard this before,you aren’t wrong.
This time,our friendliest star will align with the Earth’s equator.
When the sun’s rays do this,the Northern Hemisphere flips to astronomical spring. Along the East Coast,this happens at 5:01 a.m. EDT while the West Coast will start spring at 2:01 a.m.
So what happened last time we said spring was beginning?
Meteorological spring began on March 1. That seasonal cousin to astronomical spring is defined as the three-month period where temperatures are generally climbing. This more rigid monthly structure allows meteorologists to keep records more easily.
(MORE:Spring Temperature Outlook)
Astronomical spring,in contrast,floats in time and date depending on when the sun’s rays cross from the Southern Hemisphere to the Northern Hemisphere. This can cause the date of spring's start to swing from March 19-21.
It is at the moment that the sun moves across the equator that day and night are balanced. Daylight will continue to increase during these spring months.
Instead of a tilt away from or toward the sun,the Earth's axis of rotation is perpendicular to the line connecting the centers of Earth and the sun during an equinox.
(MORE:Further beef up your forecast with our detailed,hour-by-hour breakdown for the next 8 days – only available on our Premium Pro experience.)
Because of that,day and night are balanced to nearly 12 hours each all over the world. You can see this in the half-sunlit and half-nighttime (dark areas) satellite loop below.
From this point on,daylight in the Northern Hemisphere will gradually grow longer until the summer solstice,which occurs on June 20. That's because Earth will be in the process of tilting toward the sun in the Northern Hemisphere.
(MORE:For even more granular weather data tracking in your area,view your 15-minute details forecast in our Premium Pro experience.)
If you’re reading us from Down Under,the March equinox marks the beginning of fall.
Daylight will now grow shorter until June's start of winter in places like Australia and South America as Earth tilts away from the sun.
Jonathan Belles has been a graphics meteorologist and writer for www.weathernow24.com for 8 years and also assists in the production of videos for Weather Now 24 en español. His favorite weather is tropical weather,but also enjoys covering high-impact weather and news stories and winter storms. He's a two-time graduate of Florida State University and a proud graduate of St. Petersburg College.
