The Science Behind the First Day of Fall

The first day of astronomical fall begins today at 10:21AM. If you recall back on September 1st, that was the first day of meteorological fall, which will continue though November 31st.

The Autumnal Equinox occurs because Earth is on a 23.5 degree tilt. Because of this tilt, the Earth has four different seasons. In our area we we live, we are lucky to actually experience and feel the differences between spring, summer, fall, and winter.

On the first day of fall, the amount of daylight and darkness (night) are almost equally the same as we transition to shorter days and longer nights. This happens because the sun's direct rays pass south of the equator. Now areas south of the equator begin spring as we begin fall.

Now once we have the Autumnal Equinox, that means the season is fall, but it may not start feeling like fall or the trees will not change their foliage on the same day. Temperatures will begin to get gradually cooler to feel more like the new season, and the tree's leaves are expected to peak with the beautiful colors around mid-October.

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