As the calendar flipped to September, the United Kingdom found itself at the crossroads of seasons, with meteorological autumn officially beginning on September 1, 2025. After what the Met Office has now confirmed as the warmest summer on record—boasting four official heatwaves and a mean average temperature of 16.13°C—the nation's weather is shifting gears, trading relentless sunshine for blustery showers and cooler breezes. For many, the abrupt change is a reminder that, despite the record-breaking heat of recent months, the UK's famously unpredictable weather is never far away.
The first week of September has ushered in a distinctly autumnal feel, with the Met Office announcing that rainy and variable weather will set the tone for the start of the new season. According to BBC, areas of low pressure are sweeping across the country, bringing wet and windy conditions, particularly on Wednesday, September 3. However, while this deep area of low pressure may cause localised gales and significant rainfall, forecasters say it is not severe enough to be classified as Storm Amy—the first name on the Met Office’s new 2025/26 storm list.
For those hoping for a last gasp of summer—perhaps a so-called ‘Indian summer’—the outlook is mixed. Rumors have swirled in the media about the possibility of temperatures soaring back up to 30°C in early September, with some weather charts suggesting southern England could see a resurgence of heat starting Monday, September 8. Yet, the Met Office remains cautious. Speaking to The Independent, meteorologist Craig Snell stated, “Our general trend, as we go through to the second week of September, is that, on the whole, for the UK, it is probably going to remain on the changeable, unsettled side of the weather.” He added, “It looks like there will be some drier and brighter spells at times...It will be early September, so in any sunnier moments, it will still feel fairly warm out there.”
Indeed, the forecast for the first week of September points to temperatures hovering around the seasonal average—between 13°C and 22°C, depending on location. The BBC reports that by Sunday, September 7, a pulse of warmer air from the near-continent could nudge temperatures up to 25°C or 26°C in southeast England. Norfolk and Suffolk are expected to see the best of the weather midweek, with highs of 25°C predicted, according to Heart. However, these values fall short of the official heatwave criteria, and the Met Office is quick to dispel the notion of an imminent heatwave or a true ‘Indian summer.’
To clarify, the term ‘Indian summer’ traditionally refers to an extended spell of warm weather occurring later in the autumn—typically in October or November—after the first frosts, rather than in early September. While September heatwaves are not unheard of, as evidenced by the remarkable stretch in 2023 when the UK saw seven consecutive days above 30°C (with a peak of 33.5°C in Faversham, Kent, on September 10), such extremes are not in this year’s forecast. The hottest September day ever recorded in the UK was a sweltering 35.6°C in Bawtry, South Yorkshire, back in 1906. This year, there’s no sign that temperatures will come close to those historical highs.
Instead, the Met Office’s long-range forecast, as reported by multiple outlets including Heart and The Independent, anticipates a period dominated by low pressure systems between September 5 and 14. This means the country can expect showers or longer spells of rain, with the heaviest downpours likely in western regions. Thunderstorms, hail, and gusty winds are also possible, especially if any deep areas of low pressure develop in the vicinity. “Some of these showers will be on the heavy side, maybe the odd rumble of thunder and some hail mixed in to some of them too, but they will be moving through steadily on a fairly brisk wind in the brighter moments,” said Craig Snell, as quoted by The Independent.
The weather is expected to remain unsettled throughout the week, with further blustery showers and longer periods of rain. The Met Office’s outlook for mid-September and beyond suggests a mixed bag: “Low pressure is likely to dominate much of this period, bringing changeable weather conditions with showers or some longer spells of rain at times. There will likely be some drier, more settled interludes, particularly at the start of the period. Temperatures are likely to be close to average, perhaps turning warmer than average later in the period.”
Travel disruptions could be a concern, particularly in Scotland and northern parts of the UK, where heavy rainfall is forecast to move eastwards on Tuesday, September 2. The aftermath of Hurricane Erin and Tropical Storm Fernand in late August has already brought “unseasonable” rainy weather to parts of the country, with the Met Office issuing yellow weather warnings for some regions. Over the recent bank holiday weekend, temperatures reached 29.1°C in Hawarden, Flintshire, and 24.5°C in Magilligan, Londonderry—breaking local records for Wales and Northern Ireland, but signaling the end of the summer’s dry spell.
Looking ahead, while short-lived spells of drier and more settled weather are possible—especially early and late in the September 5 to 14 period—temperatures are expected to remain close to or slightly below average overall. Any warmer interludes will be fleeting, and there is no indication of a prolonged heatwave. As The Independent notes, “The week after next is a little bit too early to nail down exactly what will go on. Our general trend though, as we go through to the second week of September, is that, on the whole, for the UK, it is probably going to remain on the changeable, unsettled side of the weather.”
This year’s summer, with its relentless heat and four official heatwaves, will go down in history. According to Met Office scientist Emily Carlisle, the average temperature up to August 28 stood at 16.13°C, surpassing the previous record of 15.76°C set in 2018. Remarkably, this means that all five of the UK’s warmest summers have occurred since the year 2000—a trend that speaks volumes about the changing climate.
For now, as autumn settles in, Britons can expect a return to familiar territory: raincoats at the ready, umbrellas in hand, and an eye on the ever-shifting forecast. The promise of a golden autumn may yet arrive, but for the moment, the UK is being reminded that its weather—however extraordinary the summer—remains as unpredictable as ever.
