UK weather: Brits to be BATTERED by a month's rainfall today - see all 42 areas

Dozens of areas of the UK are set to be battered by one month's worth of rainfall today with flooding also expected in some regions.

Millions living in southern England and South Wales will be drenched by a staggering amount of rain this morning and into this afternoon. Rainfall totals will vary widely with between 20-30mm falling in some places while 40-60mm could be dumped within a period of between six to nine hours.

Typically, about 72mm of rain falls in Plymouth, Devon, in an average September but around 60mm could fall there today, nearly reaching the monthly total. Southampton, which also falls under the yellow rain warning, sees an average of 60mm of rain in a standard September, and downpours there could be severe.

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The yellow rain warning stretches from Cornwall, in the South West, up to South Wales and Herefordshire and reaching down to West and East Sussex.

Coastal gales are also likely for a time, especially along the English Channel coasts, warns the Met Office. "Heavy rain and strong winds will move northeast through the first part of Wednesday, followed by heavy showers and some thunderstorms, these becoming more isolated through the afternoon," the Met Office said.

42 areas across 13 counties are expected to be affected by today's downpours. The Environment Agency's official flood alerts have been issued for Devon, particularly around the River Axe area.

The alert has been flagged for between Axminster and Axmouth, which will be vulnerable this morning. The downpours could also be thundery at times across Wales.

People in areas affected by flooding have been asked to consider preparing a flood plan and an emergency flood kit. This should include a torch, spare batteries, a first aid kit, essential medications, bottled water and a battery-powered radio.

Much of the UK will experience rain in the afternoon, although with less than expected along the south coast. It will be a marked difference from the dry weather on Tuesday.

The Met Office said in its forecast for today: "Cloud and outbreaks of heavy rain will spread northeast, with heavy, blustery, and sometimes thundery showers following behind. Breezy, especially in the south where coastal gales are possible. Temperatures remaining near average but tempered somewhat by the strong winds."

For tonight, the Met Office added: "Turning drier away from the far southwest, where persistent rain will continue to affect Shetland. Clear spells developing for most overnight, before further frequent, heavy showers spread across the south."

Areas under rain warning London & South East England

Bracknell Forest

Brighton and Hove

Buckinghamshire

East Sussex

Hampshire

Isle of Wight

Kent

Oxfordshire

Portsmouth

Reading

Southampton

Surrey

West Berkshire

West Sussex

Windsor and Maidenhead

Wokingham

South West England

Bath and North East Somerset

Bournemouth Christchurch and Poole

Bristol

Cornwall

Devon

Dorset

Gloucestershire

North Somerset

Plymouth

Somerset

South Gloucestershire

Swindon

Torbay

Wiltshire

Wales

Blaenau Gwent

Bridgend

Caerphilly

Cardiff

Merthyr Tydfil

Monmouthshire

Neath Port Talbot

Newport

Rhondda Cynon Taf

Swansea

Torfaen

Vale of Glamo