A storm system will spend the second half of this week tracking from the southern British Isles to Italy, threatening to produce hail in some communities and flooding around the Alps.
Rain accompanying the storm will dampen southern Ireland, southern England and northern France on Thursday before dropping down to the Alps Thursday night into Friday.
Initially on Thursday, the rain will mainly interfere with outdoor plans and cause minor travel delays. This includes around London during the afternoon and evening hours.
As the rain descends across the Alps, there is concern for heavier rain to develop and trigger flash flooding. Rainfall amounts will generally be on the order of 50 to 100 mm (2 to 4 inches) by the end of Friday.
South of the steady and heavy rain, thunderstorms will rumble from France to northern Italy. With plenty of cold air above the surface, some of the thunderstorms will produce hail.
These hail-producing thunderstorms will rattle western France on Thursday, then southern France and northern Italy on Friday. The afternoon and evening hours will be the most likely time for the thunderstorms to develop.
Nantes and Montpellier, France, and Milan and Florence, Italy, are some of the communities at risk to see hail. The threat will remain south of Paris, despite a rumble of thunder likely on Thursday.
The wet weather accompanying the storm is expected to remain north of Madrid, but residents will welcome the cooler air that will be drawn in to end the week.
Madrid set a new all-time May record high on Wednesday when temperatures soared to 37 C (99 F). The previous May record high was 36.4 C (97.5 F) from 1950, according to AccuWeather.com Meteorologist Eric Leister.
After another summerlike day on Thursday, a more comfortable high in the middle 20s C (mid-70s F) is expected on Friday.