Spring officially begins in the Northern Hemisphere on March 20 with the vernal equinox as the entire world experiences an equal amount of daylight and darkness.

As the Northern Hemisphere welcomes spring today, the Southern Hemisphere is marked with the first day of autumn.

Thursday is the first day of spring, or the vernal equinox, in the Northern Hemisphere. During an equinox, the center of the ...

The sun is directly above the equator during both equinoxes ... "causes the sun to appear above the horizon when the actual position of the sun is below the horizon," the weather service says.