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Wild Weather: South Yorkshire Floods

Simon Rogerson
By Simon Rogerson
Meteorology Department at the University of Reading

Flooding in Ecclesfield in 2007
Flooding in Ecclesfield in 2007

Although South Yorkshire does not cover a large land area, the difference in weather as you travel across the county from west to east can be quite startling.

UK weather patterns are dominated by westerly winds blowing relatively warm and moist air from the Atlantic Ocean.

As this air moves over the high ground of the Pennines, it has to rise up and cool, often bringing cloud and rain.

As such the western edges of the county, in the hilly parts of Sheffield and Barnsley see mean annual precipitation of between 1000mm and 1500mm a year.

River Dearne flooding in Darfield
The River Dearne caused this flooding in Darfield; one of many rivers in South Yorkshire to burst its banks after the heavy rain in 2007

Although this does not make these towns by any means the wettest in the country, this is comfortably above the mean annual precipitation across all of England.

However, as you travel eastwards through Sheffield, Barnsley and Rotherham the high grounds of the Pennines quickly give way to lower lying and flatter areas.

The leeward side of the hills sit in a rain shadow cast by the Pennines and are amongst the driest parts of the UK with Doncaster and the east of the county only receiving half of the annual precipitation of their neighbours to the west.

Unsurprisingly the lowest temperatures, highest winds and most amounts of snow in the county are found in the high grounds to the west.

The stunning views, attractive villages and perfect hill walking countryside of the Peak District must seem like scant reward for weather to the hardy hill folk of Sheffield and Barnsley.

Flooded garden
Many homes and gardens were flooded - some people could not return home for months

However, having such dry regions offered no escape to the county during the extreme weather events in the summer of 2007.

Between the 13th and 15th June Sheffield received over 130mm rain, more than double the average total June rainfall.

The heavy rain was neither limited to Sheffield nor just to these three days and overall the entire county experienced June rainfall totals of over 400% of average total June rainfall.

This unusually high amount of rain caused the River Don to burst its banks bringing widespread flooding.

As well as causing the tragic deaths of two people in Sheffield, the flooding also brought substantial damage and disruption across the entire region with residents of affected areas such as Toll Bar near Doncaster unable to move back into their homes for many months after the waters had receded due to the numbers of homes that had been damaged and in need of repair.

Windiest dayWindiest Day 114 mphHigh Bradfield on 13th January 1984

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