Home
Weather London
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
Career
    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
Nighttime marina with sailboats and glowing harbor lights beneath electric-blue noctilucent clouds stretching across the dark twilight sky.
Saturday, 23 May 2026

A silvery haze in the sky

The season of the luminous night clouds
Split image showing a nighttime lightning strike beneath storm clouds on the left and a lightning detection map with dense storm activity across central England on the right.
Wednesday, 27 May 2026

Trickier than you think

Why it's hard to pinpoint thunderstorms
Weather warning map of Wales and western Britain showing a yellow thunderstorm alert with lightning symbols, alongside a large warning triangle for lightning.
Wednesday, 27 May 2026

Wales & western England

Thunderstorm watch continues
All weather news
This might also interest you
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
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
plit image showing a double rainbow over a rocky shoreline on the left and sheep grazing in a green field under stormy clouds on the right.
Sunday, 2 November 2025

Your weather - Your shots

Mixed conditions on an unsettled week
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

facebooktwittertikToklinkList