When Autumn begins
11th October, 2016
Having enjoyed the Indian summer weather of recent weeks, you’d be forgiven for thinking that autumn hasn’t yet arrived. So, the questions is "When does autumn really start?”.
Well that depends on whether you are referring to the astronomical or meteorological autumn.
There are two separate dates which could be said to mark the start of autumn. One is defined by the Earth's axis and orbit around the sun and the second is a fixed date which is used by meteorologists for consistent spacing and lengths of the seasons.
The meteorological seasons consists of splitting the seasons into four periods made up of three months each. These seasons are split to coincide with our Gregorian calendar making it easier for meteorological observing and forecasting to compare seasonal and monthly statistics. Meteorological autumn began on 1 September and ends on 30 November when we move to winter.
In contrast, this year’s astronomical autumn began on 22 September and ends on 20 December. The astronomical calendar determines the seasons due to the 23.5 degree tilt of the Earth's rotational axis in relation to its orbit around the sun. Both equinoxes and solstices are related to the Earth's orbit around the sun.
Solstices and equinoxes are considered to be the astronomical transition points between the seasons and mark key stages in the astronomical cycle of the earth. In a year there are two equinoxes (spring and autumn) and two solstices (summer and winter).
On the autumn equinox, day and night are of roughly equal length.
So importantly, with that settled, what is the weather usually like in autumn?
Well as you’ve guessed it can vary. The graphic opposite shows the wettest, warmest, sunniest, driest and coldest autumns on record. As we have had a warm autumn so far we can expect the rest of it to be markedly cooler. In fact, the need for winter gritting in parts of the UK might not be far around the corner as only last week minus temperatures were recorded at Balmoral.
With colder weather on the horizon, now’s the time to protect your business by arranging winter gritting and snow clearance. It’s never too early to get a plan in place, call us on 01728 633900 to find out more about our bespoke winter maintenance service and get a free quote.