The autumn equinox arrives this week, marking the point when the Northern Hemisphere begins to tilt further away from the sun.
However, parts of the UK will experience weather more typical of summer, with temperatures in southern and southeastern England at times reaching levels more commonly associated with July. Conditions will not be settled everywhere, though, as weather fronts bring rain and stronger winds to the north and west.
Very warm in the southeast on Tuesday
A weather front will move into northwestern parts of the UK on Tuesday, bringing increasing cloud to Scotland and Northern Ireland. Rain will be intermittent initially, but is expected to become heavier and more persistent across parts of Northern Ireland during the afternoon.
Much of England and Wales will be rather cloudy, particularly in northern and western areas, with a few spots of rain possible. The best of the sunshine will be across southeast England, where temperatures could reach 25°C or perhaps 26°C. These values are closer to the July average than those usually expected in late September. Temperatures will reach the low 20s more widely, including some areas affected by cloud and rain.
It's a warm start to the new week, but how much sunshine can you expect?
— Met Office (@metoffice) September 20, 2026
Here's what you need to know 👇 pic.twitter.com/DZrR0xY5qn
Rain becoming heavier on Wednesday
There is some uncertainty over the development and exact position of the weather system from Tuesday night into Wednesday. An upper trough, an area of lower pressure higher in the atmosphere, is expected to approach the UK and interact with the weather front. This could cause the air to rise more strongly and intensify the rainfall along the front.
Wednesday may therefore begin wet across eastern Northern Ireland, central and southern Scotland and the far north of England. Rain could be heavy at times, leading to difficult travelling conditions during the morning. It will then move south into northern and central England and parts of Wales, becoming increasingly showery as it reaches central areas.
Southern and southeastern areas will hold on to some warmth ahead of the front, although increasing cloud means temperatures are unlikely to be as high as on Tuesday. Brighter skies will follow the rain across the north and west, accompanied by fresher and less humid air.
A chilly start but plenty of sunshine on Thursday
Thursday will bring a noticeable change following the passage of Wednesday’s rain. Clearer skies and lower humidity will allow temperatures to fall widely into single figures overnight. Rural parts of Wales and northern England could fall to around 4°C, while parts of rural Scotland may reach 1°C or 2°C. A touch of frost is possible in places, giving the day a distinctly autumnal start.
Despite the early chill, Thursday should begin bright across much of the country. Many areas will retain sunny skies into the afternoon, with light winds in the east. Temperatures should recover into the high teens or low 20s in the sunshine. Scotland and Northern Ireland will become cloudier and increasingly breezy as the next weather system approaches, bringing rain into the far northwest later.
READ MORE: Do changing seasons affect the jet stream?
Wind and rain returning on Friday
A deep area of low pressure will pass towards Iceland, with an associated front extending across Scotland and Northern Ireland. Strong winds are expected in the northwest, with a risk of gales in exposed parts of northwestern Scotland.
Rain will move south across Scotland and Northern Ireland, coming and going through the day. It may eventually reach northern England, west Wales and possibly Cornwall. The precise position of the front and the intensity of its rainfall remain uncertain.
Ahead of the rain, southern and southeastern England should experience sunny spells. After another cool start, temperatures could climb towards the mid-20s. Conditions will feel notably cooler in the northwest, where strong winds will bring frequent showers behind the main rain band.
The northwest to southeast contrast continues
The rain band should begin to move away around the start of the weekend, but the broad weather pattern is likely to persist. Further weather fronts may reach northwestern areas, bringing rain at times and a strong breeze. Meanwhile, high pressure is expected to remain influential towards the southeast, producing a greater chance of dry, sunny and unusually warm conditions for late September.
Keep up to date with weather warnings, and you can find the latest forecast on our website, on YouTube, by following us on X and Facebook, as well as on our mobile app which is available for iPhone from the App store and for Android from the Google Play store.
