UK Heatwave 2026: Every Record That Fell
The June 2026 heatwave gave the UK its hottest June day on record — a provisional 37.3°C at Santon Downham, Suffolk on 26 June. The June record fell three days running under a Red Extreme Heat Warning. Here is every record that fell, and how it stacks up against Britain's past heatwaves.
For a country whose old June record had gone unbeaten for half a century, the last week of June 2026 was extraordinary. The heat didn't just break the UK's June record — it broke it on three consecutive days, climbing from 36.7°C at Merryfield in Somerset to a provisional 37.3°C at Santon Downham, Suffolk on 26 June. The Met Office issued a Red Extreme Heat Warning — its most serious — and more than 150 weather stations, some with over a century of data, logged their hottest-ever June day.
This was the UK front of a far larger event: a heat dome that made late June 2026 the worst heatwave ever recorded across Europe, with Spain hitting 45.1°C and Germany a provisional 41.5°C. Here is what fell at home.
The Records That Fell
Every figure below is from the Met Office and is provisional until formally ratified. Temperatures are shown °C first.
| Record | New mark | Where | Date | Previous |
|---|---|---|---|---|
| UK hottest June day | 37.3°C / 99.1°F | Santon Downham, Suffolk | 26 June | 35.6°C (Southampton, 1976) |
| UK hottest June day (earlier in the run) | 36.7°C / 98.1°F | Merryfield, Somerset | June 2026 | 35.6°C (Southampton, 1976) |
| Wales hottest June day | 35.9°C / 96.6°F | Cardiff | June 2026 | previous Welsh June high |
| Northern Ireland June high (tied) | 30.8°C / 87.4°F | Castlederg, Co. Tyrone | June 2026 | 30.8°C (tied) |
| UK & Wales warmest June night | 23.5°C / 74.3°F | Cardiff, Bute Park | 25 June | 20.0°C (2023) |
| England warmest June night | 23.2°C / 73.8°F | Hastings, East Sussex | 26 June | 22.7°C (1976) |
For where these sit in the all-time picture, see the hottest days in UK history, ranked — the June record still sits well below the UK all-time high of 40.3°C (2022).
The Overnight Story
The daytime peaks grabbed the headlines, but the nights are what worried health officials. On 25 June, Cardiff's Bute Park stayed at 23.5°C overnight — a UK June record that obliterated the previous 20.0°C from 2023. England set its own June minimum record the next night: 23.2°C at Hastings, beating a 1976 mark.
A “tropical night,” where the temperature never drops below 20°C, denies the body the overnight cooling it relies on to recover. That is why heat becomes deadly during multi-day events rather than single hot afternoons — the risk accumulates when homes, hospitals and care settings never get a chance to cool down. Heat is consistently the deadliest form of extreme weather in Europe, and warm nights are a big part of why.
Is This Normal? The Historical Context
Hot spells in June are not new — the difference is the ceiling. The legendary 1976 summer, whose 35.6°C June record 2026 finally broke, arrived on the 50th anniversary almost to the week. But 1976 was a long, dry heatwave that topped out lower than 2026 did in a matter of days. The 2003 European heatwave pushed the UK to 38.5°C in August; 2019 reached 38.7°C in July; and 2022 broke the 40°C barrier for the first time at 40.3°C.
Set 2026 against that sequence and it fits a clear pattern: heat records that once stood for decades now fall within a few years of each other, and June is doing what only July and August used to. You can trace the full climb in the hottest days in UK history, and the same signal globally in 2026 as the hottest year on record.
What's Next for Summer 2026
The late-June heat broke down as cooler Atlantic air pushed back in — the usual British ending to a heatwave. But July and August are peak heatwave season, and further hot spells through the rest of summer 2026 would be entirely typical. We'll update this page as any new records fall. To see whether a given spell is genuinely exceptional or just a warm week, you can compare it to any past UK summer with our historical lookup.
Frequently Asked Questions
How hot did it get in the UK in 2026?
A provisional 37.3°C at Santon Downham, Suffolk on 26 June — the hottest June day ever recorded in the UK. The June record was broken on three consecutive days.
Was June 2026 the hottest June on record?
It set the hottest single June day on record (37.3°C, beating 35.6°C from 1976), and more than 150 stations logged their own June highs, per the Met Office.
What is a Red Extreme Heat Warning?
The Met Office's most serious heat alert — it signals a risk to life for the whole population, not just vulnerable groups, with likely disruption to travel and daily life.
What was the hottest day of 2026 so far?
As of early July, 26 June, with a provisional 37.3°C at Santon Downham. Further heat episodes are typical in July and August.
Sources
Temperature and overnight records are from the Met Office June 2026 heatwave recap and its June-record news releases, with peak-day reporting from ITV News. Late-June 2026 figures are provisional pending Met Office ratification.