More thundery downpours on the way, but more settled from Thursday

There are multiple Met Office weather warnings in force across the UK for today and tomorrow, as low pressure takes centre stage for once this summer, rather than high pressure. 

Today, there are thunderstorm warnings in force across southern and central Scotland, N. Ireland, Wales and SW England. Rain warnings are in force for northern England and N. Ireland too. For Monday there is a thunderstorm warning covering much Scotland, away from the far north, and much of England, away from the southwest.

Sunday has seen widespread heavy showers and well-scattered thunderstorms develop across much of England and Wales, spiralling around the low near the southwest of England but also some warm sunny spells in between The exception has been northern England where there’s been more  in the way of cloud and a band of more prolonged thundery rain moving north..Scattered slow-moving showers and thunderstorms across southern and central Scotland too this afternoon. So you’ll be very lucky in the UK today if you’ve managed to stay dry.

The band of rain across northern England will spread north across southern Scotland and N. Ireland overnight, showers fading elsewhere and becoming mostly drier with clear spells, away from SE England and East Anglia - which will see further thundery showers spread northeast overnight.

Rain spreading north across the north and showers returning to the SE tonight, further widespread showers developing on Monday

Looking at the synoptic detail over the next few days, an upper level low will move east in across SW England today, before drifting east across southern England overnight. Meanwhile, a surface low over the Celtic Sea Sunday lunchtime will track southeast into northwest France by Monday. 

Upper low moves across the south tonight before elongating Monday then drifting east on Tuesday, replaced by an upper trough on Wednesday across the south, which disrupt to form a cut-off low over mainland Europe from mid-week

Upper low moving across southern England will elongate north across the UK on Monday, as it slows and is squeezed north by an upper level ridge over eastern Europe and Scandinavia. Shallow low pressure circulation will also develop over the UK on Monday and drift north, with a slack and showery flow across most areas. Heavy showers and thunderstorms look to develop quite widely and, as they will be slow-moving, given weak steering flow, there is a risk of some localised flooding.

AROME model shows heavy showers and thunderstorms developing across eastern areas of England on Monday afternoon 

Monday’s upper low will weaken and drift away east into the near continent on Tuesday, a brief weak ridge will build in, before an upper trough moves in off the Atlantic in the afternoon and evening., Another day of sunshine and showers on Tuesday, though showers more scattered and generally lighter, with low risk of thunderstorms. 

The upper trough will be across SE England and northern France on Wednesday, before amplifying and disrupting into mainland Europe by Thursday - forming a cut-off upper low - which will become slow-moving over the Alps, southern Germany and northern Italy. High pressure will be building in across the far west, while low pressure will present to the east. This will bring a cool and showery north or northwesterly flow across much of the UK on Wednesday, showers heavy and thundery across southern England.

Showers early on in the week, before easing  and becoming more settled  from Thursday - as high pressure builds in from the west

The upper low looks to be the catalyst for storms over the Alps and northern Italy and northern Balkans later in the week, with flooding a concern. 

Meanwhile, a ridge looks to extend from the Azores in across the far west of Europe temporarily. This means the showers should ease across the UK, with Thursday looking drier and sunnier in the west, though some showers still possible in the east. Friday looks to be the driest day of the week at the moment, with sunny spells and temperatures around average, though some showers can’t be ruled out.

No signs of another heatwave returning, high pressure looks to remain close to the southwest through next weekend and perhaps into early the following week too, but with a westerly flow off the Atlantic across the UK, keeping weather changeable, but with most rain in the north and west. SE England could be dry, sunny and warm much of the time.