A Weather Watcher's Guide to the Clocks Going Back

4 minute read

The clocks go back on Sunday, the 25th of October 2026. At 2am, British Summer Time (BST) ends and the hour between 1am and 2am happens twice, which gives most of us a little extra time in bed leaving a few clocks around the house to be adjusted.

It is also the point in the year where the evenings close in earlier, mornings are brighter, and the weather begins to behave differently as the nights get longer. This guide covers what to expect, what to watch out for at home, and the story of how Britain came to put the clocks back in the first place.

Why do we change the clocks? A short history

Until the 1840s, towns kept their own local time which was set by the sun. Clocks in Bristol ran around ten minutes behind London, which made little difference to a stagecoach but a huge difference to a railway timetable. The railways adopted Greenwich Mean Time (GMT), and it became the legal standard across Great Britain in 1880.

The idea of moving the clocks for the seasons came from William Willett, a builder from Chislehurst in Kent. William would notice on early morning rides, how many houses still had their blinds drawn in the middle of a bright summer morning. In 1907 he published a pamphlet called "The Waste of Daylight" which proposed that the clocks move forward in small steps through the spring and back again in the autumn.

He campaigned for years, arguing that lighter evenings would cut lighting costs, since homes and workplaces would need less artificial light, and that people would gain more daylight hours for walking, sports, or gardening after work. Sadly, William died in 1915, a year before the idea became law. Germany became the first country to implement daylight saving nationally on 30 April 1916 and Britain followed a few weeks later on 21 May.

Between 1968 and 1971, Britain remained on British Summer Time all year round. Dark winter mornings, particularly in Scotland, ended the experiment, and the familiar pattern of the clocks changing twice a year is what still carries on today. The argument about stopping the changes altogether has not gone away, and opinions still remain divided.

What does the autumn weather do as the evenings darken?

Late October is a good time to keep an eye on your instruments, because the longer nights bring some of the most noticeable weather of the year:

First frosts: On a clear, still night the ground loses its warmth quickly. In many parts of the country the first ground frost arrives around now, depending on how clear and calm the nights are. A thermometer placed in a shaded spot away from walls gives you a true air temperature. On a clear, still night, a reading of around 3°C or 4°C often means the grass is already frosting, because the ground cools faster than the air above it.

Mist and fog: Those same calm nights are when mist gathers in valleys, river meadows and low-lying fields. A morning that begins in thick fog under high pressure often clears to a bright, still afternoon, and watching it burn off is one of the small pleasures of the season.

Air pressure: Autumn is when a barometer earns its place on the wall. Readings above 1020 hPa usually go with settled weather, and readings that sink below 1000 hPa tend to bring wind and rain. The direction of travel matters more than the number itself. A steady fall over several hours is the signal worth noting, so tap the glass gently and see which way the needle moves.

Do other countries change their clocks at the same time?

Not always, and some do not even change them at all. The United States moves its clocks back on Sunday 1 November this year, a week after the UK, because American law ties the change to the first Sunday in November, while the UK and most of Europe follow the last Sunday in October. For that one week, London and New York are four hours apart instead of the usual five.

Countries close to the equator mostly skip the change entirely, since day length barely varies through the year and there is little extra evening light to gain. Japan, India, China and even most countries in the Middle East do not change their clocks either, and in the US, Hawaii and most of Arizona stay on the same standard time all year.

The southern hemisphere runs the other way round. In places such as New Zealand and much of southeast Australia, the clocks go forward in September and October because their spring arrives while our summer is turning to autumn.

A weather watcher's checklist for the weekend of 25th October

• Set your clocks on Saturday evening.
• Note the sunset time on Saturday and again on Sunday, and see the difference for yourself.
• Read your barometer morning and evening and write down which way it is moving.
• Check the thermometer on the first clear night for your first frost.
• Look out for mist on the first still morning under high pressure.

Enjoy the extra hour on Sunday, and the clear, cool mornings that tend to come with it! If you are thinking of adding a clock to a hallway, living room, or kitchen before the darker months, our clock collection comes in a range of styles and each pairs beautifully with a barometer or thermometer nearby.