BBC monthly outlook
High pressure frequently keeping fronts at bay
Saturday 14 September – Sunday 22 September
Some rain at times
Saturday will be fine across southern and central Britain, with lots of sunshine for England and Wales. Central and northern Scotland will be rather cloudy and windy with outbreaks of rain, and gales across the far north. It will become cloudier across Northern Ireland and southern Scotland, with a risk of rain here later in the day. A band of cloud and a few spots of rain will sink south towards north Wales and the Midlands on Sunday, giving a rather cloudy and damp day here. Dry with a good deal of sunshine for southern England, and rather warm and humid too, but breezier across Scotland with the odd shower in the west. Monday will see the band of cloud and patchy rain slowly fade across southern England and Wales, with westerly winds continuing to bring a few further showers to western Scotland and the Northern Isles. There will be a good deal of sunshine elsewhere.
A chilly but generally clear night will follow, while Tuesday and Wednesday will be fine but rather cool with sunny periods and patchy cloud, and perhaps a few light showers edging into North Sea coasts of England and Scotland. After mid-week, high pressure is expected to slowly drift east across the UK, giving a good deal of fine and sunny weather almost everywhere, while temperatures will slowly climb as winds shift to an east and then south-easterly direction. Shetland will see some breezier and wetter weather at times though. With light winds expected for many areas, mist and fog may develop more widely during the nights, particularly across England and Wales.
Monday 23 September – Sunday 29 September
A warm start, but unsettled for a time mid-week
A warm start across southern and central Britain, with south or south-westerly winds pushing temperatures well above normal for one or two days. Fronts will remain closer to Scotland and Northern Ireland, bringing a chance of rain and stronger winds. These rather unsettled conditions look like becoming a little more widespread across the country through the middle of the week, when a few weakening fronts may move south and east across England and Wales. However, much of southern and south-eastern England will see little rain, perhaps with a couple of cloudier and breezier days instead.
It looks like high pressure will build back across the UK from the south-west through the latter half of the week, with a couple of low pressure areas then passing to the north of Scotland. Winds falling light at times and lengthier sunny spells developing. Any wet and windy weather should fade across northern Britain too, although it may be cloudier and breezier with a risk of rain in the far north at times.
Monday 30 September – Sunday 13 October
Frequently calm and sunny
The end of September may see some drier and warmer days once again, with high pressure, perhaps located over the near Continent, providing a warm south or south-easterly airflow for a time. Therefore, the month could end on a relatively dry and calm note for many, with areas of low pressure kept at bay in the Atlantic. As we head into early October, it looks more likely that high pressure will lie just to the west of the UK, in the north-east Atlantic, with low pressure areas more frequent across Scandinavia. With the UK often lying between these two systems, there could occasionally be some breezier and wetter weather for the north and east, perhaps with a couple of weakening fronts bringing some showers in from the north-west.
While Scotland may see some cooler west or north-westerly winds at times, high pressure should maintain a good deal of warm, dry and calm weather for western and south-western areas, where there should also be some good spells of Autumn sunshine. This same general weather pattern looks set to continue into the second week of October, although high pressure may occasionally extend further north by this stage. This would allow more frequent north-westerly airflows to filter across the country, pushing temperatures below average across northern areas. Lots of sunshine, particularly across western areas, while cloud and the odd shower may perhaps drift in from the North Sea at times.
Will we see Atlantic low pressure systems roar into life during the second half of October, bringing much-needed rainfall to southern Britain?