26 Nov 2012

How much longer will the rain and floods continue?

The past week has seen much of the UK lashed by low pressure after low pressure, bringing gales, heavy rain and flooding.

Whilst this type of weather is to be expected during autumn, there is a significant problem this year – the ground is saturated.

Normally in autumn, the ground has the capacity to absorb heavy rainfall, but after all the rain that has fallen through late spring and summer, the ground in many places is sodden. So rather than rain being soaked up by the ground, it stays above it, causing surface and river flooding.

It’s remarkable to think that earlier this year the main concern was drought, following two consecutive dry winters that had left water resources under a lot of pressure.

River flows and reservoirs were very low and ground water levels comparable to those experienced in the drought of 1976. As a result, some water companies in central and eastern parts of England were forced to put water restrictions in place, with hosepipe bans introduced.

However, during the last eight months, the situation has gone from one extreme to another. The UK had its wettest April and June ever recorded, and this summer has been the wettest in 100 years.

Earlier this month, the Environment Agency, in conjunction with the Met Office, released its autumn/winter flooding outlook.

It highlighted that following such a wet summer, the risk of flooding would be higher than usual through autumn and winter – especially in northern and western parts of England and Wales.

Flood risk during next 24 hours

There is still some heavy rain to come across England and Wales during the next 24 hours – including for places that have been hit by flooding already.

However, the focus of the heavy, persistent rain has shifted northwards, which means that northern parts of England and Wales will see the worst of the wet weather.

In these areas, 30-50mm, locally 70mm could fall by the end of Tuesday. As a result, the Environment Agency’s flood risk forecast puts northern parts of England and Wales at greatest risk from flooding, as well as Northamptonshire.

Despite the highest risk of flooding predicted for these areas, there’s still a risk of flooding in other parts of England and Wales where heavy showers fall – especially in the places that have been hit in recent days.

When will it stop raining?

Thankfully, a big change of weather type will occur from midweek onwards across the UK. Low pressure will move into mainland Europe and high pressure will start to build from the west.

This means that it will settle down significantly, with much drier weather for all places – welcome news, especially for flood-hit areas. However, as well as becoming drier, it’s also going to turn much colder as a northerly wind sets in.

Temperatures will be in the range of 2-7C by day, dropping to around -2C at night, with widespread frosts and a risk of ice as water seeps out of sodden ground and freezes.

Whilst most places will be dry with a lot of sunshine, there will be some showers for northern, western and eastern coasts of the UK, which could be wintry – initially over the hills, but even down to lower levels by the weekend.

Where can I find the latest flood and weather warning information?

England and Wales – Environment Agency

Scotland – Scottish Environment Protection Agency

Northern Ireland – Rivers Agency

For the latest five day forecast and weather warnings, visit the Channel 4 Weather website, or you can follow me on Twitter – @liamdutton

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