Talk of a UK “heatwave” is back as weather maps start to show a notable jump in temperatures towards the end of May and into early June. Forecasts based on major weather models suggest that parts of the country could climb well into the mid‑20s, with some projections hinting at highs around 27–30C in the warmest spots. But while headlines focus on a possible sizzler, the Met Office is more cautious, stressing that much of May will still feature unsettled spells before any sustained warmth arrives.
According to model output reported this week, temperatures could surge to around 26–27C in parts of England around 22–24 May, particularly in the south and southeast. Weather maps indicate that many southern counties may see highs of 24–25C for several days, with parts of South Wales and the Midlands also turning notably warm. In some scenarios, later runs of the GFS model even show parts of the country nudging close to 30C if conditions line up perfectly.
The Met Office defines an official heatwave using temperature thresholds that must be met or exceeded for at least three consecutive days. These thresholds vary by region, typically between 25C and 28C, with the higher bar in the southeast and slightly lower values further north. As things stand, forecasters say temperatures are likely to become “rather warm” towards the end of May, especially in southern areas, but they have not yet confirmed that an official heatwave is likely.
In the shorter term, the outlook remains mixed. The Met Office expects changeable and at times unsettled weather through the middle of May, with low pressure bringing periods of rain or showers interspersed with drier spells. Temperatures during this phase are expected to be around or a little below average for the time of year, before gradually recovering as high pressure builds from the south later in the month.
By late May, more settled conditions are forecast to develop, increasing the chances of longer sunny spells and higher daytime temperatures. Confidence in the exact numbers is still limited at this range, but the broad signal is for a shift towards warmer, drier weather, particularly for England and Wales. Northern Ireland and Scotland may also see some improvement, though temperatures there are likely to be closer to seasonal norms than the potential mid‑20s seen further south.
For anyone planning outdoor events, barbecues or trips to the coast, the key takeaway is that late May looks more promising than the cool, unsettled conditions that have dominated earlier in the month. However, with showers and changeable weather still in the mix before high pressure fully establishes itself, it is wise to keep an eye on updated forecasts closer to the time. UV levels will also rise as the sun climbs higher, so sun protection becomes increasingly important even on days that do not feel exceptionally hot.
In summary, the UK is likely heading for a spell of significantly warmer weather, with some areas potentially flirting with heatwave criteria if temperatures stay above threshold values for several days. Whether it becomes an official heatwave or simply a welcome warm spell, many people will see a marked improvement by late May after a largely cool and unsettled spring. As always, the Met Office will refine its guidance as new data arrives, so checking the latest outlook remains the best way to plan ahead.
