A storm system is set to batter southern England on August 26, stretching 300 miles from Devon to the Norfolk coast.
Weather maps show intense rainfall starting around midnight, with heavy downpours expected across most of southern England through the early morning hours.
WX Charts data reveals rainfall rates could reach 10mm per hour in the worst-affected areas.
The most intense period begins around midnight on August 26, with a powerful band of rain sweeping from London and Southampton to south Wales. WX Charts data show the storm could hit counties including Hampshire, Berkshire, Buckinghamshire, Oxfordshire, London, Hertfordshire, Cambridgeshire, and Norfolk.
By 6am, the storm system moves northward, with areas between Birmingham and Manchester becoming the worst affected.
The rainfall intensity may drop sharply by noon, with light showers remaining in some places.
The Met Office's long-range forecast says: "A deep area of low pressure is likely to develop in the North Atlantic. This is linked to Hurricane Erin, which is expected to start to bring a change in weather to the UK, though the timing of this is uncertain."
The forecast warns that high pressure may "become increasingly eroded from the west" as low pressure systems move in from the Atlantic. Temperatures are likely to start off "warm or very warm before trending towards average" as the unsettled conditions take hold.
Sources used: "Express", "Daily Star" Note: This article has been edited with the help of Artificial Intelligence.