The Met Office has warned that parts of the UK could see 20 to 30mm of rain falling in just a few hours from Wednesday, August 26, as a period of heavy showers and thunderstorms is set to follow five official heatwaves in London this summer, which saw temperatures reach 38.1C.
The warning comes from Met Office Deputy Chief Forecaster Mark Sidaway, who said that while many areas will start the week dry and increasingly warm, attention is turning to the potential for heavy rain and thunderstorms from Wednesday onwards. He noted that warmer and more humid air moving north across the UK increases the likelihood of heavy rain, with some places potentially seeing 20 to 30mm in a few hours, and higher totals where thunderstorms repeatedly affect the same locations.
London's wet turn after scorching summer
London is set to be drenched by the deluge, following a summer that saw five official heatwaves and a peak temperature of 38.1C. The wet weather will begin on Wednesday (August 26) with increasing showers and high humidity, according to the Met Office forecast.
The heavy showers and thunderstorms are expected to follow as low pressure develops. Low pressure occurs because the air weighs less on the ground and is pushed upward, where it cools and condenses into clouds. The BBC Weather team and WX Charts also forecast a similarly miserable week ahead.
Rain maps and hourly totals
Weather maps from WX Charts show a massive rain cloud slamming into the capital at 3am on Thursday (August 27). The heaviness of rainfall correlates with the colours on the map, indicating about 0.4mm of rainfall per hour at that time.
Sidaway added: "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 to keep updated on the increasing risk of impactful weather during the latter part of the week."
London forecast for the coming week
The Met Office London forecast for the coming week is as follows: Today (Sunday, August 23) – high of 24C and low of 14C, sunny intervals. Monday, August 24 – high of 22C and low of 16C, sunny intervals. Tuesday, August 25 – high of 25C and low of 17C, sunny intervals. Wednesday, August 26 – high of 26C and low of 18C, sunny intervals. Thursday, August 27 – high of 25C and low of 16C, sunny intervals. Friday, August 28 – high of 22C and low of 16C, light shower day. Saturday, August 29 – high of 22C and low of 17C, sunny intervals.
The Met Office advises residents to stay up to date with the forecast as the week progresses, given the increasing risk of impactful weather in the latter part of the week.
