Parts of Ireland experienced their highest temperatures of the year yesterday, but other places were hit by thunderstorms and flooding.
Met Éireann is forecasting an abrupt end to the recent warm humid spell, which saw temperatures in Antrim and Derry rise as high as 27 degrees Celsius yesterday.
A Met Éireann weather station in Monaghan recorded a high of 26 degrees Celsius while much of the eastern half of the country basked in warm hazy sunshine.
In contrast, heavy thundery downpours soaked much of Munster from lunchtime yesterday, with localised flooding reported and humidity reaching a high of 97 per cent at the Valentia weather station in Co Kerry.
Afternoon temperatures struggled to reach 16 degrees in places.
Rain will extend over the whole country today, with very heavy thunderstorms and windy conditions expected in some areas.
Met Éireann has issued localised flood warnings, with between 25 and 50mm of rain forecast in places.
The thunderstorms will push northwards, bringing torrential rain, but will gradually clear from the south.
Forecasters have warned that the showers will be "heavy in their own right", with temperatures returning to the high teens and low 20s throughout the country.
Fresher, less humid weather will move up from the south, with sunshine and showers forecast for tomorrow and the weekend.
Today's thunderstorms are not expected to be as severe as the violent storms which hit south-western France on Tuesday, leaving four people dead and more than 70 injured.
Among those who died were two tourists, a Dutch man in his 40s and an 11-year-old German girl, who were killed in the Landes area, south of Bordeaux.
Two teenagers were also killed during the storms.
A 16-year-old boy died of a suspected heart attack at a campsite in Gennes, near Saumur.
In the neighbouring Pyrenées-Atlantiques area, a 17-year-old youth riding a scooter was killed when he crashed into another vehicle.
Three people were still missing after the sudden storms broke a heatwave in France late on Tuesday evening.
Falling pine trees devastated tents and trailers at a campsite in Biscarosse, a beach resort between Bordeaux and Biarritz. High winds and hail showers knocked out power supplies in the area and interrupted train services.
Several hundred people had to seek shelter in local schools and municipal buildings.
The French emergency services were called out repeatedly during Tuesday night to tackle fires and assist with incidents of flooding and collapsed roofs.
In the UK, temperatures reached 33 degrees Celsius yesterday on the hottest July day since 1989. However, wet weather is expected to reach the southern coast of Britain later today.