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
Heat-health alerts ahead of heatwave. Across England. . . Tuesday 7 July 2026
Temperature map of the UK and western Europe showing hot conditions across Britain, with temperatures reaching 33°C near London, 29°C around Cardiff, 24°C near Liverpool, and a large heat warning symbol highlighting elevated heat risk.
Tuesday 7 July 2026

Across England

Heat-health alerts ahead of heatwave
June heatwave also heated up the oceans. Across Europe's waters. . . Wednesday 1 July 2026
Europe temperature map with sea temperature icons showing coastal water temperatures of 20–24°C around the British Isles, 20–25°C in the Baltic Sea, 25°C in the Black Sea, and 25–27°C across parts of the Mediterranean.
Wednesday 1 July 2026

Across Europe's waters

June heatwave also heated up the oceans
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
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
New records for England and Wales. Broken again tomorrow?. . . Thursday 25 June 2026
Temperature map of southwest Britain on 25.06 showing extreme heat across southern Wales and southwest England, with Bute Park in Cardiff highlighted at 34.2°C and Yeovilton at 36.4°C amid widespread deep red heat zones.
Thursday 25 June 2026

Broken again tomorrow?

New records for England and Wales
Seasonal warmth between spring thunder. Your weather - Your shots. . . Sunday 19 April 2026
Split image showing coastal sunset with layered lenticular clouds over rooftops and palm trees on the left, and a green valley with river and hills under soft daylight on the right.
Sunday 19 April 2026

Your weather - Your shots

Seasonal warmth between spring thunder
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