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
Increasingly gusty as low approaches. Overnight winds. . . Wednesday 1 July 2026
Wind forecast map of the UK and northern Europe showing a low-pressure system centred near the Faroe Islands, with orange wind zones, airflow streamlines, and gusts reaching 45 mph in northeast Scotland and around 35 mph across Ireland and northern England.
Wednesday 1 July 2026

Overnight winds

Increasingly gusty as low approaches
June temperature record broken again. Three days running. . . Friday 26 June 2026
Temperature map of eastern England showing extreme heat around Ipswich and nearby areas, with temperatures reaching 36°C near Cambridge and a large red thermometer icon highlighting intense heat.
Friday 26 June 2026

Three days running

June temperature record broken again
Record-breaking heatwave in Europe. New records. . . Thursday 25 June 2026
A map showing extremely high temperatures across Western Europe and a warning symbol. On the right, people cool off at a fountain in front of the Eiffel Tower during the heatwave in Paris.
Thursday 25 June 2026

New records

Record-breaking heatwave in Europe
All weather news
This might also interest you
Turbulent weather in the Canary Islands. Storm and rain. . . Friday 12 December 2025
Weather graphic showing rain and wind fields over the Canary Islands and a central warning symbol.
Friday 12 December 2025

Storm and rain

Turbulent weather in the Canary Islands
Historic Storm Éowyn arrives. On this day.... . . Saturday 24 January 2026
Split image showing a person in a yellow jacket struggling against strong winds and heavy rain on a street at night on the left, and an Irish wind forecast map on the right with red and purple shading, gusts up to 75 mph, and a wind warning icon, divided by a curved white line.
Saturday 24 January 2026

On this day...

Historic Storm Éowyn arrives
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