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Unsettled conditions dominated the Bank Holiday in early May, bringing rain and showers to many parts of the country. For the following Bank Holiday there was heavy rain. After a reasonably dry start to June, extremely heavy and prolonged rain fell on to an already soggy UK, leading to serious floods which threatened lives and caused substantial damage to property. Tragically some people died and thousands more had to spend nights in temporary accommodation or were left without power.

Part of the reason for the heavy rain was the jet stream - a band of strong winds in the upper atmosphere that influence how weather systems that bring rain to the UK will develop. As the jet stream was stronger than normal, depressions near the UK were more intense. Some of these depressions pulled in the very warm and moist air to the south of the UK, generating exceptionally heavy and intense rainfall.

What we did

• We played a vital role throughout the summer, providing highly accurate forecasts and warnings ahead of the heavy rains.
• Before and during the floods we worked with and advised emergency planners across the UK including the police and military rescue teams, the Environment Agency, the Scottish Environment Protection Agency and COBR (the Civil contingencies committee which leads responses to national crises).
• We issued early warnings of the severe weather several days ahead to advise the public on the possible impacts.
• As more heavy rain fell on already flood-hit areas, we kept everyone informed as the downpours deposited well over three times the monthly average rainfall for June in some places.

The results

• While it is not easy to forecast extreme weather, the heavy rain was well forecast, with Met Office forecasters predicting the heavy and prolonged rainfall.
• There is no doubt that things would have been much worse without early warnings from the Met Office.

What happened in June

On Monday 25 June prolonged heavy rainfall resulted in many parts of north and east England being flooded.

Map of risk of disruption in June

Weather conditions

Surface synoptic analysis map, Monday 25 June at 6pm

Days before the actual flooding, the ground around the worst-hit areas became saturated by very heavy rain. Many sites in Yorkshire received at least a month's rainfall in 24 hours.

On Monday 25 June a slow-moving area of low pressure brought a prolonged period of heavy rain to northern and central England. Hitting the already saturated north-east, the water had nowhere else to go and, as a result, led to major flooding.

Impacts

• Five people died.
• Surface water flooding in Hull.
• Widespread disruption and damage to more than 7,000 houses and 1,300 businesses in Hull.
• River Don burst its banks, flooding Sheffield and Doncaster.
• Flooding in Derbyshire, Lincolnshire and Worcestershire.
• Highest official rainfall total was 111 mm at Fylingdales (N Yorkshire). Amateur networks recorded similar totals in the Hull area.
• There were fears that the dam wall at the Ulley Reservoir near Rotherham would burst.

A heightened alert state was retained during the week 25-30 June, because of the threat of further rain.

What happened in July

The second event caused localised flash flooding across parts of southern England on the morning of 20 July, and later in the day across the Midlands.

Map of the risk of disruption in July

Weather conditions

Surface synoptic analysis map, Friday 20 July at 12 UTC.

A slow-moving depression centred over south-east England, drawing warm moist air from the continent across the UK. Heavy and slow moving rainfall moved northwards during the day.

Impacts

• Widespread disruption to the motorway and rail networks.
• In the following days the River Severn and tributaries in Gloucestershire, Worcestershire, Herefordshire, Shropshire broke banks and flooded surrounding areas.
• River Thames and its tributaries in Wiltshire, Oxfordshire, Berkshire and Surrey flooded.
• Flooding in Telford and Wrekin, Staffordshire, Warwickshire and Birmingham.
• The highest recorded rainfall total was 157.4 mm in 48 hours at Pershore College (Worcestershire).

The future

• In August, Sir Michael Pitt conducted an independent review of the flooding. The review recognised our forecasts and warnings had been timely and accurate and also praised the performance of our Public Weather Service Advisors.
• A key recommendation of the Pitt review, after the floods of summer 2007, was that the Environment Agency and the Met Office should work together, through a joint Flood Forecasting Centre , to improve the capability to forecast, model and warn against flooding.
• Developments in Met Office capability such as 1.5 km resolution models and probabilistic forecasts will help the UK to be more resilient to severe weather.