Homes have been flooded, travel disrupted and firefighters called out to rescue a group of campers stranded on a riverside site as Storm Francis swept across the UK. Winds of up to 70mph and heavy rainfall battered much of the country, and emergency services warned that trees could be brought down and power cuts triggered. In St Clears in Carmarthenshire, south-west Wales, firefighters with rescue boats were called to a flooded campsite at dawn on Tuesday after a group of holidaymakers was stranded. Homes and businesses were flooded in areas of south Wales including Neath and Llanelli. Roads were closed and trains cancelled or delayed. National Rail tweeted that a line had been blocked in Neath. Traffic Wales warned of “extremely poor driving conditions” while South Wales police tweeted an image of a car stuck in flood water in the village of Merthyr Mawr in Bridgend. Strong winds caused the first Severn Bridge to be closed periodically. Emergency services were searching the River Taff after reports that a canoeist may have capsized near Taff’s Well village, six miles north of Cardiff. A search was also launched in the city centre after reports of a person having entered the Taff near the Principality Stadium shortly before 8.40am on Tuesday. The Met Office issued a yellow warning, saying severe gales were forecast on Tuesday and Wednesday. It reported rainfall overnight of more than 40mm in parts of Wales and in Devon. The Met Office said a deep area of low pressure was crossing the UK, bringing gusts of up to 70mph in exposed western locations and also heavy rain for many. It said: “A yellow wind warning is in force for the whole of Wales and most of England until midday on Wednesday. While not exceptional, winds this strong are unusual for August and they will be accompanied by some heavy rain in places, with possible transport disruption and impacts on outdoor activities. “Large waves are also expected in coastal areas around the south-west including the Bristol Channel throughout Tuesday, moving along the English Channel as the day progresses. Beachgoers are advised to take extra care. “The rain is expected to be heaviest in Northern Ireland and south-west Scotland where 60-90mm in total could fall as the storm moves from west to east. Storm Francis is due to clear to the east of the UK by Wednesday lunchtime.” The Met Office chief meteorologist, Andy Page, said: “The UK is in for another unseasonably wet and windy spell with Storm Francis arriving. There will be strong winds and heavy rain, especially in the west of the UK.” The Maritime and Coastguard Agency warned the public that cliff edges would be slippery and crumbly after the large volume of rain recently around the coast. It spoke to a camper at the weekend who pitched perilously close to a cliff edge at Portreath in north Cornwall. The poor weather may mean no play is possible on the last day of the final cricket Test match between England and Pakistan in Southampton. The England fast bowler James Anderson is hoping the rain will pass and give him the chance to take his 600th Test wicket. The Met Office has not had two named storms in August since the process started in 2015, but Francis follows Ellen, which struck last week. No new storm is currently forecast this month, meaning the next one will begin with A rather than G, as the storm-naming calendar resets on 1 September.