What Clothes Should I Take for a Two-Week UK Vacation in September?: A Complete Guide Organising a two-week UK holiday from September 8 to September 22 entails preparations for the unpredictable early-autumn climate of the country. Sunny afternoons, chilly mornings, rainy days, and windy evenings can happen in just one day in the UK. A good way of packing for such a climate entails planning the wardrobe in terms of layers and comfort rather than packing one piece of clothing