Met office
UK Outlook for Monday 3 Sep 2018 to Wednesday 12 Sep 2018:
On Monday and Tuesday a slow moving band of cloud and increasingly patchy rain is likely to lie across UK. Away from this, it should be dry with variable cloud and some long sunny spells, although outbreaks of rain may affect the far north later. Temperatures will be warm, possibly very warm in the south and east, but closer to normal elsewhere. Through the rest of the period more settled conditions are likely to become established, with a good deal of dry weather, and increasing sunshine. However, the far north and west may still occasionally be windy, with some rain at times. There will be some warm days, especially in the southeast, but there may be some chilly nights, with an increasing risk of fog.
UK Outlook for Thursday 13 Sep 2018 to Thursday 27 Sep 2018:
Throughout this forecast period it seems most likely that the weather pattern will change only slowly, and this will maintain a good deal of dry, warm and settled weather, although there may be some brief spells of more changeable conditions. Northern and western areas are most likely to have occasionally wet and windy spells, but these are likely to be short-lived, with some more settled interludes at times here too. Daytime temperatures are expected to be above average overall, with some warm days in the across the south and east, and with the warmer conditions perhaps spreading further north and west at times. However, as the nights lengthen through September, any longer clear nights may lead to some quite low overnight temperatures, with an accompanying risk of patchy fog.
https://www.metoffice.gov.uk/public/weather/forecast%3C/div%3E%3C/div%3E