Brits have been warned to brace themselves for thunderstorms bringing flooding and travel disruption in another summer weekend washout.
The Met Office has issued a yellow warning for heavy showers and thunderstorms across parts of England, Wales and Northern Ireland on Saturday.
The warnings run from midday until 10pm and cover large parts of each nation, with the exception of some coastal areas, London and other regions of the south east.
Forecasters said places that avoid the worst of the storms could still be hit with transport disruption and possible flooding.
This could include spray, standing water and hail affecting driving conditions, delays to train services, the short term loss of power, potential damage from lightning strikes and possible flooding of a few homes and businesses.
National Highways advised drivers to plan ahead and take care on the roads, with fire services across the country also encouraging caution.
Met Office forecaster Greg Dewhurst said up to 40mm of rain is expected to hit the areas within its warning on Saturday.
"On Saturday we will see a band of heavy rain push north-eastwards across the UK, followed by sunshine and heavy showers," he said.
"Sunday will see the heavy rain clearing to bright and sunny spells and heavy showers in the east."
The wet start to the weekend comes after areas including London have already seen a month's worth of average rainfall for August with 12 days still to go.
Mr Dewhurst said the city of London has had 117% of its usual August rainfall already, with 60mm of rain falling on the capital up to August 19, compared with 51mm usually seen over the entire month.
Northern Ireland has had 91mm of rain - 93% of its 97mm average for the month.
Meanwhile, other areas have been exceptionally dry, including North Yorkshire which has had less than 50% of its usual rainfall.
Mr Dewhurst said overall UK temperatures and rainfall for the time of year are "about average".
On Saturday, the mercury is set to rise to around 21C in London, 20C in Cardiff, and 18C in Edinburgh and Belfast.
Localised heavy rain and hail has already caused "significant problems" for harvests, according to the National Farmers' Union (NFU).
A spokesperson for the union said this year's harvest was delayed due to cold spring temperatures, but it is too early to say how much profits will be impacted and whether consumers could see a rise in food prices.
UK Met Office weather forecast where you are
North West
Heavy, and locally torrential rain lasting most of the day, particularly in the north of the region. In the south, the rain will be followed by heavy thundery showers through the evening. Feeling muggy with light winds. Maximum temperature 19C.
Thundery showers will continue through the evening, easing by the early hours. A cloudy and muggy night following, with some patchy light rain and low cloud over the hills. Minimum temperature 14C.
North East
Outbreaks of rain, heavy at times, moving north and east across many areas on Saturday. Then turning brighter across southern, western and later some central parts, but with showers, heavy and thundery in places.
Heavy rain or showers becoming restricted to parts of northern and eastern England later on Saturday, whilst dying out elsewhere. Mist and low cloud in the north and east.
On Sunday the rain in the east is expected to clear, with cloud breaking to allow sunny intervals for most areas. Some showers developing, but many southwestern areas remaining dry. Warm in the sunshine.
Next week there is expected to be a mainly fine and dry spell, though a few light showers are likely in places. Warm, perhaps very warm for some western areas, otherwise close to normal.
East
After a mostly dry start on Saturday with some brightness further east, cloud will thicken as rain moves in from the west. This turning heavy at times through the afternoon, with a risk of thunder mainly in western areas. Light winds and a maximum temperature of 23C.
Heavy perhaps thundery showery rain will slowly move away eastwards through the evening, although lingering in northeastern areas overnight. Staying cloudy for all with light winds. Minimum temperature of 15C.
Sunday will be mostly cloudy. Some scattered showers developing, perhaps with the odd heavy shower in the afternoon. Becoming breezy on eastern coasts. Maximum temperature of 21C.
Generally drier and brighter from Monday, with winds easing, although the odd shower possible Monday morning. There will be warm sunny spells at times.
West Midlands
A band of heavy rain will cross the region from the south west, clearing by early to mid-afternoon on Saturday. This will be followed by widespread torrential and thundery showers, with hail possible too. Light winds and feeling humid. Maximum temperature 20 °C.
Heavy thundery showers will only slowly ease through the evening, especially in the east of the region, leaving a cloudy night with some clear spells. Feeling muggy. Minimum temperature of 12C.
A drier day for Sunday, but still a scattering of showers around, some heavy. Showers fading through the afternoon leaving more frequent sunny spells. Feeling warm in the sunshine. Maximum temperature of 22C.
A much more settled spell of weather to start next week with sunny spells. Feeling warmer as a result. Dry for most, but the chance of an isolated light shower.
East Midlands
Drier at first in the southeast, but otherwise cloudy with long periods of rain, which will be heavy at times on Saturday. Rain turning showery through the afternoon, perhaps thundery in places. Light winds, with fog over the hills. Maximum temperature of 21 C.
Heavy perhaps thundery showery rain will slowly move away eastwards through the evening, although perhaps lingering in north eastern areas overnight. Staying cloudy for all. Light winds. Minimum temperature of 15C.
Sunday will be mostly cloudy. Some scattered showers developing, perhaps with the odd heavy shower in the afternoon. Possibly some sunny spells later in eastern areas. Maximum temperature of 22C.
Generally drier and brighter from Monday, with light winds. There will be warm sunny spells, although some coastal low cloud and mist may spread inland during the overnight periods.
South East
After a mostly dry start with some brightness further east, cloud will soon thicken as rain moves in from the west on Saturday. This turning heavy at times through the afternoon, with a risk of thunder mainly in western areas. Light winds. Maximum temperature of 23C.
Any lingering heavy perhaps thundery showers will ease through the evening, but remaining largely cloudy for most. Becoming breezy on southern coasts. Minimum temperature 13C.
Sunday will be mostly cloudy. Some scattered showers developing, perhaps with the odd heavy shower in the afternoon. Breezy on coasts. Maximum temperature 23C.
Generally drier and brighter from Monday, with warm sunny spells, although the odd shower possible Monday morning. Breezy at times on southern coasts.
South West
Heavy rain will clear from eastern counties through Saturday morning, leaving behind sunny spells. However, heavy downpours will then develop, torrential and thundery in places. Feeling rather humid with light winds. Maximum temperature 22C.
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 14C.
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 22C.
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.
Wales
Heavy rain clearing through Saturday morning, clearing the north east of the country by mid-afternoon. Heavy showers will follow on from this, locally torrential and thundery, with hail possible. Feeling humid with light winds. Maximum temperature 20C.
Heavy and thundery showers will clear eastwards through the evening, only slowly decaying. A dry night then follows with variable cloud and some clear spells. Feeling muggy. Minimum temperature 14C.
A much drier day on Sunday. There will still be a scattering of light showers, but these will clear through the afternoon leaving sunny spells. Feeling warm in the sunshine. Maximum temperature 22C.
A dry and settled spell of weather to start next week with sunny spells. Feeling warm in the sunshine. Mainly dry, but the chance of an isolated light shower.
Scotland
A mostly cloudy Saturday with scattered showers or some longer spells of rain, but some drier spells of weather too. Feeling rather warm and humid. Maximum temperature 18C.
Showery rain in places in the evening, occasionally heavy at first. Becoming drier into the early hours but still with the odd shower. A rather warm and humid night. Minimum temperature 14C.
The west will see some sunny intervals and the odd afternoon shower on Sunday. The east will be rather cloudy and mostly dry, some brightness later in the afternoon. Warm. Maximum temperature 21C.
Dry and warm with some spells of sunshine. Overnight low cloud cloud may linger across the east into the afternoons in places.
Northern Ireland
A mostly cloudy Saturday with scattered showers or longer spells of rain. Some heavy, thundery downpours likely in the afternoon. Feeling rather warm and humid. Maximum temperature 19 C.
Showers, locally heavy at first, gradually dying out this evening. Then the rest of the night will be mostly dry. Rather warm and humid. Minimum temperature 14C.
Cloud breaking through the morning to leave a mainly dry day with some warm afternoon sunshine. Maximum temperature 21C.
All areas will be dry with some good spells of sunshine, becoming warm. Light wind.
