The UK could be heading for another spell of unusually warm weather, with forecasting models suggesting temperatures may climb towards 30C for several days in early September.
The possible return of heatwave conditions comes after a week of thunderstorms, heavy rain, and unsettled weather across parts of the country. Although temperatures are expected to remain relatively modest in the short term, weather models indicate a warmer spell later in the forecast period.
The latest projections suggest some parts of England could see temperatures rise to 28C or 29C between September 5 and September 7.
UK Temperatures Could Rise Again in September
Current weather models indicate that temperatures may begin to recover towards the end of the first week of September.
According to the GFS weather model, temperatures could reach around 28 °C in southern and western England on September 5.
The warmth could then spread further north the following day. On September 6, highs of around 28 °C could become more widespread, potentially reaching areas as far north as Yorkshire.
By September 7, temperatures could climb to approximately 29C in parts of eastern and western England, while central and southern regions could see highs between 27C and 28C.
If the forecast develops as currently projected, some locations could experience three consecutive days meeting the UK’s heatwave threshold.
Could the UK See an Official Heatwave?
A key point is that an official heatwave does not simply depend on temperatures reaching 30 °C.
The UK’s heatwave criteria are based on location-specific temperature thresholds. The threshold is higher in areas such as south-east England, where temperatures are typically warmer, and lower in cooler parts of the country.
Under the current criteria, the threshold is around 28 °C in parts of south-east England, while it can fall to approximately 25 °C elsewhere.
An official heatwave is declared when temperatures reach or exceed the relevant threshold for three consecutive days.
That means a period of 27C to 29C could potentially qualify as a heatwave in some parts of the country, even though it would not match the extreme temperatures seen during the UK’s hottest spells.
Weather Maps Show Warmer Conditions Across England and Wales
Temperature anomaly maps for the period also show warmer-than-average conditions across parts of England and Wales.
Areas shaded in orange and red indicate locations where temperatures could be significantly above the seasonal average.
However, the maps represent forecast guidance rather than a guarantee. Weather models can change considerably as the forecast period approaches, particularly when predicting conditions more than a week ahead.
The possible warm spell should therefore be treated as an indication of what could happen rather than a confirmed three-day heatwave.
Met Office Predicts Possible Very Warm Spells
The Met Office has also suggested that warmer conditions could develop at the beginning of September.
Its outlook for August 31 to September 9 points towards generally unsettled conditions, with showers and longer periods of rain possible across the UK.
The forecast suggests rainfall could remain above average for the time of year, with north-western areas potentially experiencing the wettest conditions.
Strong winds are also possible at times.
However, the Met Office says there could be periods of drier and more settled weather, particularly across southern parts of the country, later in the forecast period.
It also highlights the possibility of short-lived warm or very warm spells, especially in southern areas.
Thunderstorms Bring Heavy Rain Before the Warmer Spell
The potential September heat comes after a very different spell of weather.
Thunderstorms have brought heavy rainfall to parts of England and Wales, with warnings issued for potentially disruptive conditions.
Some areas could experience intense rainfall, lightning, localized flooding, and strong winds.
The unsettled conditions have provided a sharp contrast to the warmer weather experienced across the UK earlier in the summer.
Temperatures may still reach around 28 °C in some locations during the current spell, but they are expected to fall towards the low 20s for much of the rest of the week.
Why Forecasts Can Change
Long-range weather forecasts are useful for identifying possible trends, but they become less certain the further ahead they look.
A forecast showing 29 °C several days from now does not necessarily mean that exact temperature will occur.
Weather models are updated regularly as new atmospheric data becomes available. This means the timing, location, and strength of any potential warm spell can change.
For that reason, the possible September heatwave should be monitored through updated forecasts from the Met Office and other trusted weather services.
Warm September Weather Could Arrive After a Cool Spell
If the current model predictions prove accurate, the contrast could be striking.
After thunderstorms and heavy rain, temperatures could once again approach 30C in parts of England.
Southern areas are currently the most likely to benefit from the warmer conditions, although some northern areas could also experience temperatures well above average.
The potential three-day period from September 5 to September 7 is therefore attracting attention, particularly because temperatures may reach or exceed local heatwave thresholds.
What the September Outlook Really Means
Despite encouraging signs of warm weather, the broader forecast remains unsettled.
The Met Office expects showers or longer periods of rain to remain possible across the UK during early September. Rainfall totals may stay above average, especially in the north-west.
This means the country is unlikely to experience a prolonged spell of uninterrupted sunshine.
Instead, the forecast points towards a mixture of rain, showers, drier intervals, and potentially very warm periods.
For southern England in particular, the possibility of longer settled spells later in the period could bring some pleasant late-summer weather.
Heatwave or Warm Spell?
At this stage, it is too early to say with certainty that the UK will experience an official heatwave in September.
The latest weather models show the potential for three consecutive days of heatwave-level temperatures, but forecasts can change before the event.
If temperatures reach 28-29 °C across the currently highlighted areas, some locations could meet the official criteria.
For now, the message is one of possibility rather than certainty: after a stormy and wet period, another burst of summer-like warmth could be on the way.
With September approaching, weather watchers will be keeping a close eye on the latest forecasts to see whether the predicted temperatures become reality.
