Image source, Anadolu via Getty ImagesByBen RichLead Weather Presenter
Temperatures are set to climb across the UK this weekend, reaching summerlike levels in some places.
It will feel warm and muggy – especially where there are sunny spells – although heavy rain also features in the forecast.
The warmth will persist into Monday in many areas but nowhere is expected to reach heatwave criteria and cooler conditions are due to return by midweek.
Computer weather models paint a very mixed picture for the second half of September but, while there are likely to be some warm spells, there are currently no definitive signs of a heatwave.
Outbreaks of rain will spread southwards during Saturday, clearing from Scotland and Northern Ireland but continuing into the afternoon across parts of northern England, Wales and the Midlands.
Some of the rain could be heavy with a chance of thunder and lightning and will be accompanied by brisk south-westerly winds.
Southern parts of England should stay largely dry with sunny intervals and it will feel particularly warm and humid with temperatures climbing into the mid-20s Celsius – several degrees above the September average.
Typical mid-September temperatures range from 14C in northern Scotland to 19C in south-east England
On Sunday, rain may linger for a while in southern England but should clear to leave a dry afternoon for much of the UK with sunny spells and light winds.
Temperatures may drop slightly in the northern half of the country but rise a little further south. Parts of Wales, the Midlands and southern England could reach 23-25C.
Monday could be even warmer with highs of 22-26C across much of England and Wales, and 20C likely in parts of Scotland and Northern Ireland.
However, while this will undoubtedly feel warm, it will remain below the criteria for a heatwave.
This would require three consecutive days of temperatures above a threshold which varies from 25C in Scotland and Northern Ireland to 28C in the London area.
Computer models currently suggest unsettled weather will continue over the next week or so.
The jet stream is expected to bring areas of low pressure across the UK – meaning spells of rain and, potentially, some rather blustery winds.
The prospect of wet weather will be welcome for the large swathes of England and Wales that remain in drought.
Later in the month, areas of high pressure may have more influence on the weather which would mean longer dry interludes and the chance of above-average daytime temperatures.
While long-range forecasting is fraught with uncertainty and details are subject to change, there is currently nothing to indicate that a heatwave is on the cards.
Indeed, as autumn advances and the nights become longer, high pressure overhead could lead to some rather chilly mornings.
You can keep an eye on the temperatures where you are by checking BBC Weather online and the app.
