BBC monthly outlook
Wednesday 22 August—Sunday 26 August
Becoming cooler, windier and wetter
There will be a change in the weather for most parts of the country over the next couple of days, with it becoming cooler, windier and wetter than it has been for most areas. The change will start on Wednesday, when a cold front will move south-eastwards across the country. This front will bring rain to Scotland, northern England and Northern Ireland in the morning, moving
further southwards and eastwards in the afternoon. It probably won't reach the far south east of England during daylight hours, so that part of the country will remain dry but will also remain rather warm and humid throughout the day. Much clearer and fresher air will move in behind the front, so the north of the UK should have some decent sunny spells but perhaps a few showers too.
Thursday should see the front clearing south east England, with all of the UK then in the cooler and fresher air mass. There will be sunny spells and showers, the showers mainly in the north and west and some of them could be heavy and thundery. Another frontal system will cross the country on Friday, so there will be showers or rain for most areas, but perhaps more importantly, winds will turn more northerly as this system clears. This will have an impact this weekend, with Saturday looking to be a decidedly cool day. Temperatures may not reach 20C, with most areas likely to be limited to daytime highs in the mid-teens. Saturday night looks rather chilly in some areas. A ridge of high pressure should bring a reasonably dry day on Sunday, but the next weather front will be waiting in the wings.
Monday 27 August—Sunday 2 September
High pressure building back across the UK
A front moving from west to east is likely to bring rain to many parts of the country on Monday, although rain is not expected to last all day and there will be a chance of some drier and sunnier weather. With winds coming in from the west, it should be a little warmer too. Tuesday may be another unsettled and windy day for the north of the UK, with the chance of showers and rain, but the south looks likely to remain dry with sunny periods. The general trend for the rest of the week is for high pressure to start to build in from the south-west. This means that the southern half of the country is likely to see an increasing amount of fine and sunny weather, and temperatures should start to lift to average or above average. The north of the country, particularly Scotland, will not see the influence of this high pressure until later in the week so is likely to see further spells of wet and breezy or windy weather. There should be some drier and sunnier spells of weather here too and it should become a little warmer.
Monday 3 September—Sunday 16 September
A lot of warm and dry weather expected
High pressure looks likely to be the main feature of the weather again during the first half of September. In fact, there is pretty good agreement from a variety of forecasting methods for high pressure to build across a lot of north west and central Europe and remain there well into September.
So, what does this mean for the UK? The pressure pattern is fairly similar to that which we saw earlier in the summer, so it isn't much of a surprise that September looks likely to be a relatively dry month, especially in the south and west of the UK. The north could be affected by passing low pressure systems at times, so may see some rain, but even here it looks drier than average. Temperatures are also likely to be above average, although with shorter days and longer nights, it is less likely that we'll see the widespread and frequent hot weather that we saw in July, and no major late summer heatwave is currently anticipated
Next Update
How long will the dry, warm weather hold on for?
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