Heavy downpour, potentially damaging hail, and strong winds are reportedly on their way to the UK beginning Friday evening and raging on throughout the night. According to The Weather Network, a large bout of thunder and rain is expected to push northwards across Southern England, south Wales, the south Midlands, and East Anglia.
This week so far has been quite dry and cool due to a large area of high pressure residing just to the west of the UK. However, this area is supposed to move towards the east over the course of Thursday, allowing a nearby area of low pressure to move up from the south. This means that during Thursday the UK weather should remain dry, however there may be a few showers across Cornwall and Devon. By Friday, the low pressure will be at the south coast of England, forging a very humid airmass across the southern half of England and Wales. As the heat builds and the airmass itself becomes more unstable through the morning and afternoon, thunderstorms are said to begin emerging. Downpours are estimated to bring 20-30mm of rain in less than an hour locally.
Fortunately, the most severe thunderstorms will likely be very isolated, meaning some areas of the UK may avoid them altogether. However the more organized groups of rain could produce 25-50mm (or 1-2in) of rainfall, possibly more.
Friday may actually end up being the warmest day of the year, with a possibility of 27-28C across south-east England and East Anglia. With the high levels of humidity, it may actually feel like somewhere in the low 30s Celsius spanning most of southern and central England. So if you live in the UK and were hoping for some summer outings this weekend, you may want to post-pone.