I suspect your calendar says autumn will arrive on September 22, but it arrived on the first of September along with some violent weather that arrived in Paradelle.
By the meteorological calendar, the first day of autumn is always September 1 and the season ends November 30. The meteorological calendar defines the season quite cleanly as spring (March, April, May), summer (June, July, August), autumn (September, October, November) and winter (December, January, February).
Most of us were taught that the seasons change with solstices and equinoxes. Those are the astronomical seasons that follow the position of Earth in relation to the sun. Meteorological seasons follow the annual temperature cycle and match our Gregorian calendar.
The dates of the Equinox and Solstice aren’t fixed due to the Earth’s elliptical orbit of the Sun. The Earth’s orbit around the Sun is closest (perihelion) in early January. In early July, it is most distant (aphelion). That always seems odd to people. Closer is not warmer. Farther is not colder.
On the autumn equinox, day and night are of roughly equal length. Nights become increasingly longer than the days – something you are no doubt are already observing. The pattern reverse with the spring equinox.
So, when is it really the start of autumn? For those of us living on the top half of the Earth, I say it is with the autumn equinox when the northern hemisphere begins to tilt away from the Sun. That means less direct sunlight hits us so temperatures cool.
The end of summer in September – and hopefully early October – is one of my favorite times of the year. In some years and in some places in the north, we may get what has become known as “Indian Summer” – that imaginary season that occurs when temperatures are more summer than autumn from late September to mid-November.
I love it when summer gets a second chance. Sometimes the universe doesn’t play by the rules of meteorology and astronomers.