United Kingdom in September: Weather, Crowds & What to Expect
Climate Map for September
Average temperature across United Kingdom in September.
City Weather in September
| City | High | Low | Rain | UV | Feels |
|---|---|---|---|---|---|
| London | 19° | 10° | 59 mm | moderate | Cool |
| Birmingham | 17° | 9° | 74 mm | moderate | Cool |
| Glasgow | 16° | 9° | 117 mm | moderate | Cool |
| Manchester | 18° | 10° | 76 mm | moderate | Cool |
| Sheffield Cathedral | 18° | 9° | 63 mm | moderate | Cool |
| Leeds | 17° | 9° | 57 mm | moderate | Cool |
| Edinburgh | 16° | 9° | 61 mm | moderate | Cool |
High / low are average daily temperatures (°C). “Feels” reflects how hot or cold it feels, allowing for humidity.
Southeast England & London
September is pleasantly mild with a good chance of long, sunny spells - a fine month for strolling through Kew Gardens, the University towns of Oxford and Cambridge, or the coastal path at Folkestone. Sea temperatures are at their warmest, making a dip off Brighton or Hastings tempting on calm days. Tourist numbers taper off, so it’s an excellent shoulder month; bring a mix of light clothing and a warmer layer for cooler evenings.
Southwest England (Cornwall, Devon, Somerset)
Autumn in September offers some of the region’s best weather - warm daytime air and mellow light on the moors make it ideal for walking in Exmoor or exploring the Lizard Peninsula. Crowds thin quickly after the school holidays and accommodation prices fall; rain increases during late September but many fine days remain. Layer up for evenings, and expect some ferry and coastal path maintenance closures.
Wales & the Marches (Snowdonia, Brecon Beacons, Cardiff)
September often brings fine, settled weather and warm, golden light across the hills - an excellent month for walking the Glyndŵr Way or exploring coastal headlands. Crowds decline markedly after school holidays, making it a top shoulder month; mountain trails are less crowded and wildlife activity increases with migrating seabirds. Nights cool quickly, so bring an insulating layer for evenings and early mornings.
Northern England (Lake District, Yorkshire Dales, Northumberland)
September often brings some of the year’s best walking weather - clear, crisp days and cooling nights produce excellent visibility on high routes, making it ideal for long ridge walks and coastal hikes. The shoulder season sees far fewer crowds and lower accommodation prices; rivers remain full and waterfalls dramatic. Pack layers for colder summits and keep waterproofs accessible for sudden Atlantic fronts.
Scotland (Lowlands, Highlands & Islands combined)
September brings crisp, clear days ideal for whisky touring and coastal drives, and autumn colours begin to show in the Highlands and Borders, enhancing scenic routes to Isle of Skye and Glen Coe. Atlantic storm frequency begins to increase late in the month, producing windier conditions on exposed islands and headlands. Shoulder-season advantages include shorter queues and lower rates, but carry warm layers for chilly evenings.
Northern Ireland
September often brings calm, pleasant weather and is a superb shoulder month to visit with fewer crowds and mellow light perfect for photography. The Mournes and Sperrins are excellent for lengthy walks with cooler temperatures making long hikes more comfortable. Rainfall edges up through the month; a reliable waterproof and warm layers for evenings are sensible.