The Vernal Equinox occurred at 5:48 AM on GMT (Greenwich Mean Time) this morning March 20th. The Vernal Equinox occurs when the Sun crosses the line of the Equator, which splits the Northern and Southern hemispheres of the earth. That means for my time zone EST (Eastern Standard Time in the USA), which is -5 hours from GMT, it would have been 12:48 AM. We are now using EDT (Easter Daylight Time where we set the clocks ahead to get more daylight) so the Vernal Equinox actually occurred at 1:48 AM. That means it is the first day of Spring in the Northern Hemisphere. The reason the date is one day earlier this year is because it is a leap year which moved the happening forward by one day.
Vernal Equinox - This word comes from the Latin meaning Equal + Nights. This means the length of the day and the night are 12 hours long. This will slowly increase as the days progress so we will have more daylight in the Northern hemisphere until the first day of Summer in June. Conversely the Southern Hemisphere will have less daylight until their first day of winter. I made a post in December, The Change of Seasons, telling you the reason the tilt of the Earth causes the seasons to change. You can read my explanation of the happenings.
I hope this helps with the understanding of the changing seasons. Does this mean we will have no more snow in NE Ohio. Absolutely not, the seasons change slowly as the Sun males its way North. We sometime have a snow in April but the snow doesn't stay long. It will continue to get warmer each week as the days go by. Spring has sprung, can fishing be far behind?