Sussex 'severe weather alert': This is when thunderstorms could arrive with potential for further yellow warnings 'across the weekend'

A yellow weather warning came into force at 9pm on Wednesday (September 4) and lasted until 11.45pm on Thursday. A separate yellow warning, covering more locations across the UK, runs until 11.59pm tonight (Friday).

An Adur and Worthing Police social media post read: “Sussex Safer Roads Partnership have this important message for all road users! Heavy rain has led to disruption to travel across the south-east of England.

“The Met Office has issued two yellow severe weather alerts for rain until 23:59 BST on Friday.”

The weather isn’t expected to be much better this weekend.

The Met Office’s chief meteorologist Jason Kelly said: “Repeated areas of rain are likely to affect southern Britain over the next few days, generating some localised impacts into the weekend. We currently have yellow weather warnings for rain in place, and it’s likely we will be issuing further warnings across the weekend.

“It’s a different story to the north of the UK though, as high pressure brings warmer and sunnier conditions, with higher-than-average temperatures, particularly across parts of western Scotland. Eastern areas are likely to be cooler and at times, cloudier due to winds blowing off the North Sea.”

Yellow national severe weather warnings are currently in place until Friday evening across the southwest of the UK, where ‘outbreaks of heavy rain are expected widely’, the Met Office said.

Mr Kelly added: “The rain will be persistent for some and may be particularly heavy in a few places. Rainfall totals of 15-30mm are expected widely, however, the wettest areas are likely to see 40-60mm through the whole of Friday, with a lower likelihood of a few areas seeing as much as 75-100mm.

“In addition, rain may well be accompanied by thunderstorms across the southwest during the early hours of Friday morning and during the afternoon and evening, across the southeast.”

The Met Office said the jet stream – which is a ribbon of air high up in the atmosphere – ‘plays a prominent role’ in underlying patterns behind the UK’s weathe r,

Meteorologist Aidan McGivern said: “The jet stream, at the moment, is extending south across the UK. It’s currently a very elongated setup and when it is elongated this much, it can cut off from the main flow into an entirely separate circulation. This is known as a ‘cut off low’.

“You get an upper low and a surface low, just cut off from the main flow, just meandering erratically around, separate from the main flow and therefore, getting stuck somewhere. At the beginning of the week, we didn’t know where it was going to get stuck, but it looks very much now like it’s going to be to the south of the UK over the next few days, bringing heavy spells rain.”

In the South East, Saturday will see patchy rain or showers across southern and western parts by dawn.

A Met Office spokesperson said: “Further heavy showers and thunderstorms possible later Saturday. Heavy and thundery rain moving north overnight. Maximum temperature 22 °C.

“Heavy and thundery rain Sunday, turning more showery with some bright spells Sunday. Further showers or rain Monday clearing to bright spells from the west. Cooler Tuesday with late rain.”