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
Late-summer views as shooting stars fly. Your weather - Your shots. . . Sunday 23 August 2026
Split image showing a meteor streaking through a star-filled night sky on the left and wispy white cirrus clouds sweeping across a vivid blue daytime sky on the right.
Sunday 23 August 2026

Your weather - Your shots

Late-summer views as shooting stars fly
Chance of thundery showers breaking out. Over the coming days. . . Tuesday 18 August 2026
Split weather graphic showing a yellow thunderstorm warning across eastern England alongside radar with heavy showers and lightning near Sheffield, Leicester and East Anglia.
Tuesday 18 August 2026

Over the coming days

Chance of thundery showers breaking out
Damage in Germany after severe weather. Several tornadoes formed. . Weather Videos. Thursday 20 August 2026
Split image: Weather map showing thunderstorms and a tornado symbol over western Germany. On the right, severe damage to buildings and rubble on a road can be seen.
Weather VideosThursday 20 August 2026

Several tornadoes formed

Damage in Germany after severe weather
All weather news
This might also interest you
Long-term trends need a pinch of salt. 40 °C in July?. . . Tuesday 30 June 2026
Temperature radar of 2022 heatwave where the all-time temperature record in the UK was set. Warning symbol overlain.
Tuesday 30 June 2026

40 °C in July?

Long-term trends need a pinch of salt
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
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
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