Londoners reaching for the sun cream at the end of September were not imagining things: the capital roasted at 28.1C on the 29th, the month’s highest temperature, recorded at Kew Gardens as a stubborn block of high pressure settled over the south of the country.
The late blast of heat has now been written into the history books. Provisional figures from the Met Office show September was the joint-fourth warmest the UK has seen since records began in 1884, with a mean temperature of 14.6C across the month. That puts it level with 2016 and 1949, and only a fraction behind the all-time September record of 15.2C, shared by 2023 and 2006.
It is the sixth month in a row that the UK’s average temperature has landed inside the all-time top ten — a remarkable run that underlines what an extraordinary year 2026 has been. April was the seventh warmest on record, May the joint-third warmest, June and July the second warmest, August the sixth warmest, and now September the joint-fourth warmest.
The capital felt the warmth more keenly than most. The dome of high pressure over southern Britain drove the late-September surge that pushed the mercury to 28.1C at Kew Gardens on the 29th — a day forecasters had already flagged would bring 27C heat to the capital, with storms potentially hot on its heels.
For London, the September peak was the exclamation point on a year of extremes. The country endured up to five separate heatwaves: the first in late May, another in late June, two in July and one more in mid-August. June’s scorcher triggered a rare red extreme-heat warning from the Met Office, with 38.0C recorded at Lingwood in Norfolk on 26 June — a new record for the month. The hottest day of the entire year came later still, when Hartpury College in Gloucestershire reached 38.2C on 13 August.
The human cost has been stark. The UK Health Security Agency estimates that 2,877 deaths in England were associated with the May and June heatwaves alone, while an NHS survey published last month found patients had died on "suffocating" hospital wards during the hot spells, according to London nurses.
Met Office climate information scientist Mike Kendon said September’s figures fitted an unmistakable pattern: "Persistent warmth has been the theme of recent months and September is no different. While the month itself was unexceptional overall, when putting it into the context of the warm year we’ve had so far, this fits with the general pattern that we’re seeing of more frequent above average temperatures in the UK as our climate continues to change."
What does a 28.1C September day mean for the capital in practical terms? For commuters, the Tube is notoriously slow to cool — deep-level lines trap warmth, so carriages and platforms can stay stifling long after the temperature falls outside. Carrying water and allowing extra time is sensible on the hottest days. For schools, the hot end to the month arrived in the first weeks of term, with classrooms — particularly south-facing ones in older buildings — heating up through the afternoon. And the health risk is real well beyond midsummer: older people, young children and anyone with long-term health conditions are most vulnerable in hot weather, and health agencies advise checking in on neighbours and relatives, drinking plenty of water and keeping homes as cool as possible, especially overnight. London had already enjoyed a final flourish of summer earlier in the month, when forecasters promised 25C highs for a Monday.
While the thermometers soared, the rain stayed away from the south. England received just 65 per cent of its typical September rainfall, with southern and eastern areas the driest of all — in sharp contrast to Scotland, Wales and Northern Ireland, which all recorded above-average rain. Across the UK as a whole September was slightly wetter than the long-term average, but that national figure masks a deepening divide.
For London and the South East, firmly in the driest part of the country, that divide matters. Most of England and all of Wales remain officially in drought, and the Environment Agency has warned that a few wet weeks are nowhere near enough to reverse deficits built up over a dry spring and a record-hot summer. Around 30 million people in England are living under water use restrictions, while reservoir storage stands at just 56 per cent — nearly 19 percentage points below the average for this time of year. The national drought group, bringing together the Met Office, government, regulators, water companies, farmers and conservation experts, continues to meet weekly to coordinate the response.
Environment Agency chief executive Philip Duffy said: "September’s rainfall has been welcome, but a few weeks of unsettled weather is nowhere near enough to reverse the water deficits caused by a dry spring and record hot summer. We still need everyone to use a little less water to speed up the drought recovery and save more for our local rivers, farmers, and wildlife." He added that the drought will only be over when groundwater, rivers and reservoirs return to normal — something requiring "months of significant and sustained wet weather" — and warned that "the situation remains serious with drought-hit areas of England again seeing the least amount of rain over the month."
Londoners have more warm weather on the way. The Met Office is forecasting temperatures of up to 23C across the capital this weekend, with sunny spells and little rain in store.
Highs are expected to build through the weekend before peaking on Sunday, well above the average for early October. After a record-warm September, the settled spell gives the capital a fine autumn weekend to round off an extraordinary run of heat.
