The UK is expected to see a dry and sunny start to the week before heavy rain, thunderstorms and strengthening winds become increasingly likely.
Monday will be largely dry with widespread sunshine. Temperatures will be slightly above average, reaching around 25°C in south-west England and 22°C in north-west England.
Tuesday is also expected to remain mostly settled, although there will be more cloud and a chance of isolated showers, mainly in southern parts of the UK.
Heavy rain and thunderstorms possible from Wednesday
Conditions are forecast to become more unsettled from Wednesday as warm and humid air moves northwards.
Showers and longer spells of rain are expected to become more widespread, with heavy showers and thunderstorms most likely across England and Wales. A more organised area of thundery rain could also approach south-western areas later in the day.
Some places could receive between 20mm and 30mm of rain within three to four hours. Total rainfall could reach between 40mm and 60mm in some locations.
However, there remains uncertainty over where thunderstorms will develop, meaning rainfall totals could vary considerably over relatively short distances.
Met Office Deputy Chief Forecaster Mark Sidaway said: “While many areas will see dry and increasingly warm conditions at the start of the week, attention is turning to the potential for heavy rain and thunderstorms from Wednesday onwards.
“As warmer and more humid air moves north across the UK, there is an increasing likelihood of some heavy rain developing. Some places could see 20 to 30mm of rain in just a few hours, while there is also the potential for higher totals where thunderstorms repeatedly affect the same locations.
“The detail of which areas will see the heaviest rainfall is still uncertain, so stay up to date with the forecast this week.”
Heavy rain could move north on Thursday
A band of heavy and potentially thundery rain is expected to move slowly northwards across England and Wales on Thursday.
The rain could become slow-moving or repeatedly affect the same areas, increasing the possibility of higher totals and localised disruption.
Rain and winds expected to strengthen on Friday
An area of low pressure could bring a slow-moving band of heavy rain across the UK on Friday.
Some downpours could be intense and accompanied by thunderstorms. Winds are also forecast to strengthen, particularly around eastern and north-eastern coastal areas.
The precise location and severity of the heaviest rain remain uncertain, and the forecast is likely to be refined as the week progresses.
