A situation divided between North and South

The warm weather will extend to parts of Northern Ireland, as well as parts of central and western England and Wales on Friday.

There is a strong north/south divide in terms of weather, with unsettled conditions in the south, but drier and warmer conditions in the north. There is also a clear east/west divide, with cool and cloudier conditions in the east of the UK, while the west experiences warm and sunny weather.

Jason Kelly, Met Office chief meteorologist, said: “Repeated areas of rain are likely to affect southern Britain over the next few days, causing localised impacts through to the weekend. We currently have yellow weather warnings for rain in place, and we are likely to issue further warnings over the weekend.”

“The situation is different in the north of the UK, where high pressure is bringing warmer and sunnier conditions, with above average temperatures, particularly in parts of western Scotland. Eastern areas are expected to be cooler and sometimes cloudier due to winds blowing in from the North Sea.”

Weather alerts in the south

National yellow severe weather warnings are currently in force until Friday evening in the south-west of the UK, where heavy rain is expected in many places.

Jason Kelly said: “The rain will be persistent in some places and could be particularly heavy in a few places. Rainfall totals of 15-30mm are expected in most areas, but the wettest areas are expected to receive between 40-60mm throughout Friday, with a lower chance of 75-100mm in some areas.”

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

A different story in the north

Elsewhere, the north/north-west of the UK will enjoy pleasant and warm to very warm temperatures for a while. The north-east, on the other hand, is expected to see low cloud, sea fog and drizzle. Parts of western Scotland could see maximum temperatures of 26°C or even 27°C on Friday.

Brent Walker, Met Office deputy chief meteorologist, said: “Western parts of Scotland could see maximum temperatures of 26C on Friday. If the wind shifts a bit, 27C could be expected in some western areas as they experience the foehn effect, which causes the air to warm and dry on the leeward side of high ground.”

Learn more about the foehn effect.

Western Scotland in particular experienced a cool and wet summer, with 25% more rainfall than average and temperatures 0.48°C below the long-term weather average.

The impact of the jet stream

When looking at the underlying patterns of the British climate, the jet stream, which is a ribbon of air high in the atmosphere, plays an important role.

Meteorologist Aidan McGivern explains his role in the unstable weather across the South over the next few days in our 10-Day Trends video.

“The jet stream is currently extending southwards across the UK. It is currently a very elongated pattern and when it is this elongated it can split off from the main flow to form an entirely separate circulation. This is known as a ‘cut-off low’.

“We have an upper level low and a surface low, just cut off from the main flow, meandering erratically, separated from the main flow and so getting stuck somewhere. At the start of the week we didn’t know where it was going to get stuck, but it now looks like it’s going to be south of the UK over the next few days, bringing heavy rain.”

Further

Looking further ahead, we are likely to see cooler and fresher temperatures across the UK from Tuesday. Conditions are expected to remain broadly unsettled over the next week, with showers or longer periods of rain at times in all regions.

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