Is a September heatwave coming? Not quite, and here is why

The UK weather is about to take another warm turn

Temperatures will climb well above the usual levels for September, particularly across southern England, with some areas reaching the mid-20s. 

Monday is currently expected to be the warmest day, with highs of up to 26C across parts of England and Wales. Scotland and Northern Ireland could also see temperatures around 20C.

The warmer weather will arrive alongside a fairly unsettled weekend. Saturday looks particularly mixed, as rain moves down through the country after clearing Scotland and Northern Ireland. 

Northern England, Wales and the Midlands could see some heavy spells during the afternoon, while much of southern England should escape the worst of the wet weather.

Conditions are expected to improve considerably on Sunday. Much of the UK should become drier, with temperatures of 23C to 25C possible across Wales, the Midlands and southern England.

Anyone chasing one last taste of summer should pick Sunday

Despite the summer-like feel, there is an important reason forecasters are not calling this a heatwave. 

The official criteria require temperatures to exceed a specific threshold for three days in a row, and the required figure depends on where you are.

It is 25C for Scotland and Northern Ireland, while the London area needs to reach 28C.The current forecast does not come close to meeting those requirements.

Any brief return to summer conditions is also unlikely to last. Temperatures should drop again from around Wednesday as low pressure begins influencing the UK's weather, bringing more rain and potentially strong winds.

There could still be warmer spells later this month, but BBC lead weather presenter Ben Rich says there is currently no clear signal pointing towards another heatwave.

For anyone hoping to make the most of it, Sunday looks like the safest bet, while Saturday could bring heavy rain and thunderstorms in areas north of the Midlands.