Home
Weather Dublin
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
    Home / Editor's Pick /

    Meteorological vs astronomical autumn: which is it?

17:00
3 September 2025

Season start date
Meteorological vs astronomical autumn

© shutterstock / Volodymyr TVERDOKHLIB

You may be thinking that autumn doesn't start until later in September, and you wouldn't be wrong thinking this. There are two separate dates which can be used to define the start of the season.

Astronomically, the start of autumn takes places on the autumn equinox, when the length of day and night are the same in all parts of the world.

It is defined by the Earth's axis and orbit around the sun, and the exact date varies slightly each year.

This year, the autumn equinox falls on September 22nd at 07:19 pm BST, with the astronomical autumn running until December 21st.

Meteorologically, seasons are a fixed date because it is statistically easier to process the data by taking four equal quarters for each of the four seasons.

The meteorological autumn in the Northern Hemisphere is made up of September (starting on the 1st), October, November, with meteorological winter beginning on December 1st.

While the days are really getting shorter and cooler for us, the opposite is true for those in the Southern Hemisphere.

Learn more about our seasons in our weather explained video here:

What weather does autumn hold for us?read more
More on the topic
Very high UV levels during the heatwave. Sun cream at the ready!. . . Wednesday 8 July 2026
Split graphic showing a UK temperature map with hot conditions across England and Wales, temperatures reaching 32 °C near London, and a UV warning icon on the left, alongside a person applying sunscreen in bright sunshine on the right.
Wednesday 8 July 2026

Sun cream at the ready!

Very high UV levels during the heatwave
Forest fires rage in southern Europe. Drought and wind. . . Monday 6 July 2026
Split screen. On the left, a weather map of France and Spain showing the plumes of smoke from the forest fires. On the right, a fire-fighting aircraft in action.
Monday 6 July 2026

Drought and wind

Forest fires rage in southern Europe
Lee waves flow over the UK and Ireland. On the WeatherRadar. . . Monday 6 July 2026
Satellite weather map of the UK and Ireland showing parallel bands of low cloud highlighted over southern Scotland and northern England, with additional cloud streets over Wales and western England circled in white.
Monday 6 July 2026

On the WeatherRadar

Lee waves flow over the UK and Ireland
All weather news
This might also interest you
A frozen start to the weekend. Icy conditions. . . Friday 13 February 2026
UK temperature map dated 14.02 showing widespread subzero values in blue shading, with readings such as −4 in Glasgow, −3 in Dublin, and −2 in London, alongside a blue thermometer icon.
Friday 13 February 2026

Icy conditions

A frozen start to the weekend
Super Typhoon Bavi threatens Taiwan. Up to 1,000 mm of rain. . Weather Videos. Wednesday 8 July 2026
The image shows an intense tropical cyclone over the western Pacific, east of Taiwan and the Philippines. The centre of the system is depicted as a light purple and white vortex with a clearly visible eye, surrounded by a ring of red and orange areas indicating the strongest wind speeds. A white arrow marks the typhoon’s predicted track towards the north-west, in the direction of Taiwan. To the west of the storm lie the Philippines, with the cities of Manila and Cebu; to the north of these lies Taiwan, with Taipei. Further west, the Chinese coast, including Hong Kong, and parts of Vietnam can be seen. The coloured wind map shows predominantly green areas outside the storm’s core, indicating significantly weaker winds. White streamlines illustrate the typhoon’s anti-clockwise circulation in the Northern Hemisphere. The highest wind speeds are concentrated around the eye of the cyclone.
Weather VideosWednesday 8 July 2026

Up to 1,000 mm of rain

Super Typhoon Bavi threatens Taiwan
Flooding, gales, and heavy snow. Storm Chandra. . . Tuesday 27 January 2026
Split image showing aerial flooding in a town with muddy water covering roads on the left, and a rural road on the right blocked by heavy snowfall with vans stopped and a person walking in snow.
Tuesday 27 January 2026

Storm Chandra

Flooding, gales, and heavy snow
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwitteryouTubelinkList