New graphics reveal how a huge band of rain will move across the South West amid a 10-hour weather warning for thunderstorms today.
Large parts of England and Northern Ireland are gripped by the Met Office alert, which will be in place from 12pm until 10pm today (Saturday, August 21).
Exeter-based forecasters say many places will be spared from the worst but heavy showers may cause some transport disruption and perhaps flooding.
The Met Office states in its warning: “There is a good chance driving conditions will be affected by spray, standing water and/or hail, leading to longer journey times by car and bus.
“Delays to train services are possible and some short term loss of power and other services is possible, with possible damage due to lightning strikes.
“Flooding of a few homes and businesses could occur.”
Met Office's weather warning map
Rainfall maps for August 21
WX Charts' graphics below show how a heavy band of rain will move in from the west, before gradually moving east throughout the day
From 9am parts of Ireland, Wales and Scotland will see heavy rain, with persistent showers also forecast for Bristol, parts of Somerset, Gloucestershire, Wiltshire and Dorset, with areas in the east looking dry, for now.
The pattrern is much the same three hours later, with no let up for some areas.
The majority of the UK is expected to see rain come mid afternoon, with a number of areas on the south coast apparently spared.
Met Office 5-day forecast for South West
Today: Heavy rain will clear from eastern counties through the morning, leaving behind sunny spells. However, heavy downpours will then develop, torrential and thundery in places. Feeling rather humid with light winds. Maximum temperature 22 °C.
Tonight: Any showers will quickly clear from eastern counties leaving sunny intervals for the evening. A dry night then follows with clear spells. Feeling muggy with light winds. Minimum temperature 14 °C.
Sunday: A much drier day on Sunday. There is still a low risk of a shower, mainly in the east. Otherwise, sunny spells are expected, particularly through the afternoon. Feeling warmer. Maximum temperature 22 °C.
Outlook for Monday to Wednesday: A dry and settled spell of weather to start next week with lengthy sunny spells. Feeling warm in the sunshine but this tempered by a strong breeze at times.
