Parts of the UK could finally have a taste of summer this weekend, with a mini-heatwave expected to replace what has been an extremely wet first half of July. Despite the wet start to July, an improving weather pattern is expected across England and Wales, with temperatures rising and more sunshine in the coming days, with temperatures in London and the south-east potentially peaking at 30C (86F) by Friday. However, milder conditions are expected to return by Sunday. The Met Office has issued a yellow warning for rain in south-east Scotland and north-east England on Tuesday evening, predicting 15-20mm in an hour and 30-40mm over several hours. This could lead to risks of thunder and lightning and challenging driving conditions, according to a Met Office spokesperson, Nicola Maxey.Maxey said night-time temperatures could remain in the low 20s in the south-east, potentially resulting in “tropical nights” that could pose health risks to vulnerable populations. Some parts of the country have already surpassed the average rainfall for July despite only being halfway through the month. The Met Office spokesperson said England recorded 97% of its average July rainfall between 1 and 15 July, Wales 65%, Scotland 49%, and Northern Ireland 47%. London received 154% of its usual July rainfall and Dorset 120%. In contrast, Edinburgh and Dundee experienced drier conditions, with 40% and 33% of their average July rainfall respectively. Maxey said: “There are quite big regional differences but overall it’s looking like a wet month so far. There is a caveat that, with a dry couple of weeks, by the end of the month things could even themselves out.” She highlighted that a few heavy downpours had contributed significantly to the month’s totals rather than continuous wet weather. Monday – St Swithin’s Day, which traditionally forecasts the next 40 days of weather – was also marked by rain in much of England and Wales. However, the Met Office predicted changeable conditions for the coming week, with temperatures expected to hover around the seasonal average rather than persistently rainy weather.