The first day of autumn / fall is September 22 in the Northern Hemisphere. In the Southern Hemisphere it is on March 20. Using astronomical calculations however, it would fall anytime between September 1 to 15. The difference is due to the weather. They tend to lag behind the celestial calculations.
Changes in Temperature
As it follows summer, the most noticeable event will be the drop in temperature. This doesn’t suggest a sudden fall. It is rather a gradual decrease, especially in the mornings. In Florida for example, the mornings will be cooler around mid or late September. But it can also go up a little come October. The full extent of autumn usually doesn’t become evident until well into October in the US.
Changes in the Air
The first day of autumn can also be felt through the air. The heat from the Sun starts to lessen. Going around the city you’ll see the shadows get longer, indicating the coming shorter days. Nature observers also note that the sky turns very blue. The air may have a dry feel. In addition the lowering temperature produces an earthly and pleasant smell among sycamore leaves.
Leaves Changing Color
Other indications of the changing season are the leaves. The vibrant greens that summer produces will turn into varying shades of red, sand and yellow.
In parts of Canada, there’s usually a breeze or chill. This occurs even though the Sun is still very bright. The chill continues to the nighttime. It can also produce some interesting colors in the sky. In some cases the first day of autumn can give the Moon a slightly reddish glow.
Animal activities also change during the fall. Scrub birds will screech a lot while stocking up food. If there are squirrels around the area, you’ll see them gathering their food supplies as well. It’s not unusual to see them take large amounts of acorn. A lot of squirrels also store nuts.
A lot of animals store food during this period, knowing that winter is approaching. Aside from squirrels, chipmunks also store food. Among birds, it’s customary to gather food for the winter as well. There are also some cats whose fur starts to get thicker in anticipation of the winter.
Signs among People
Some people start to wear jackets and sweaters on the first day of autumn. It’s also customary for some to put up small ornaments indicative of the season.
In the past, fall was associated with the harvesting of fruits. In paintings, the season is often depicted with people gathering fruits and vegetables. Cabbage and pumpkin are particularly ripe at this time.
Birds of different species will usually gather around a single tree as they start to get ready for the cold months. The trees themselves give out signs, most notably turning into a rich brown. Martins, swifts, and other colorful birds also come together. It makes trips to the park at this time very pleasant.
The fall has been associated with melancholy times. But as the signs of the first day of autumn shows, it is actually an enjoyable period.