BBCcom_Content_Index_for_September_1_2017.txt
Monthly_Outlook_-_BBC_Weather.txt
Monthly OutlookImage source,jogo sao paulo ontem BBC Weather Watchers / Wendy HousePublished17 June 2024Updated 12 September 2025Unsettled conditions will continue for much of the coming week. However, later in September and into early October, there should be drier and calmer conditions developing in many areas as high pressure builds across the UK at times. Uncertainty will increase, with chances of the atmospheric patterns getting disturbed by the possibility of former tropical systems moving across the Atlantic, and by the middle of October there may be chances of wetter weather returning. Saturday 13 to Sunday 21 September Occasionally wet and windyChangeable weather will continue into the coming week, and a deep low pressure system moving towards Scotland will bring strengthening winds through Sunday, peaking on Monday with gales in places, especially Wales and south-west England. Heavy rain will be followed by hefty showers, some thundery, with brighter spells in between.Another couple of low pressure systems look like bringing further bouts of steadier rain and stiff winds on Wednesday and later Thursday into Friday, with further risks of gales in exposed locations. A transient high pressure ridge could deliver a drier period in between during Thursday. Temperatures will be erratic, varying near or a little below the seasonal average. The weekend should see a change, with sharp showers and brisk, blustery winds on Saturday as low pressure moves away northeastwards, followed by high pressure probably building across on Sunday, delivering a drier and calmer day.Monday 22 to Sunday 28 September A drier period is possibleThrough the following week, it looks like high pressure will remain dominant, drifting back and forth across the UK and allowing for a more settled and drier period, as the average position of the main frontal boundary shifts farther north. This will mean lighter winds overall as well. There is still going to be a chance of Atlantic frontal systems moving around the periphery of this high pressure, leading to occasionally wet and breezy conditions across the northern UK, most likely for Scotland and Northern Ireland. However, most areas should experience less precipitation than usual for this time of year. With some clearer and calmer nights, chances of fog and frost will increase but it's not going to be notably chilly, with temperatures near or a little above normal on average.Monday 29 September to Sunday 12 OctoberWetter chances later but very uncertainHigh pressure is expected to stick around for a while from the end of September into the first week of October, so similar weather should ensue. Much of the UK should have rather dry conditions enduring, although occasional fronts could brush past and bring a couple of bouts rain here and there. Precipitation amounts should be below or near average overall. Heading towards mid-October, there are some hints that high pressure could decline, with a trend towards wetter conditions possible. Temperatures are most likely to fluctuate around seasonal values or a little above. However, much will depend on exactly where this possible high pressure development sets up.The outlook is complicated by the possibility of the remnants of tropical cyclones, including ex-hurricanes, crossing the North Atlantic. These have the potential to disturb weather patterns downstream across Europe, or impact rainfall amounts and wind strengths should any directly target the UK. However, the Atlantic will have to start getting more active after a lengthy quiet period.Further aheadTuesday's update will further address the chances of drier weather developing later in September and into early October.More on this storyIs a UK heatwave in the weather forecast for September?Published3 SeptemberHow does air pressure affect our weather? Video, 00:01:13How does air pressure affect our weather?Published7 April 20221:13
