By Paul Homewood

 

As some of you may have gathered, it was rather wet here in Sheffield yesterday!

 

People are being evacuated from their homes and there is chaos on the roads and trains after torrential downpours flooded parts of northern England.

Five severe warnings – meaning a danger to life – are in place along the River Don in Doncaster with some residents being told to leave their homes.

Dozens of people slept on chairs and benches after being left stranded in a shopping centre in Sheffield overnight.

More than 100 flood warnings are in place across England

Fran Lowe, from the Environment Agency (EA), said urged people to take them seriously "as they represent a threat to life".

"Respond immediately and get out of any place affected by a severe flood warning," she said.

The north of England and the Midlands were hit by flooding chaos on Thursday night, with the highest rainfall recorded at Swineshaw in the Peak District, which had 112mm (4.4in) in 24 hours.

Parts of Sheffield experienced 85mm (3.4in) during the same period.

The average monthly rainfall total for Yorkshire at this time of year is 89mm (3.5in).

https://www.bbc.co.uk/news/uk-england-50343977 

 

It has already been described as “biblical” in the Telegraph, the go-to phrase whenever there is a downpour.

From BBC weather reports, it appears that the Sheffield rainfall total of 85mm was the highest amongst low lying sites, with 112mm up in the Peak District. Both are exceptional, but certainly not unprecedented.

The highest daily rainfall on record for Sheffield, whose records date back to 1883, is 137mm (Rivelin), which fell on 15th July 1973:

https://digital.nmla.metoffice.gov.uk/IO_f1a640eb-7f0b-4062-8370-da6c03979a69/

 

That was not the only extraordinary rainfall event that month. I have highlighted two more, which took place on the 6th, described by the Met Office as “very rare” and “remarkable”.

No doubt, someone will soon blame it on climate change. But as BBC Weather report, yesterday was no more than just another weather event, when a weather front stalled over South Yorkshire all of the day.

There is another aspect worth touching on. You will note that 85mm fell over 24 hours. But this is not the same as “in a day”.

Met Office twitter report that the total for Thursday itself was 72.88mm. The ability to pick any 24-hour period from a rolling time frame obviously increases the chance of finding a higher total than on the day itself.

https://twitter.com/metoffice/status/1192590676992634886

Fortunately flooding has only been localised, and certainly not on a par with 2007, which was the culmination of several days heavy rain.

 

Finally, let’s take a look at the monthly rainfall stats at Sheffield. Below is a chart of the wettest months:

https://www.metoffice.gov.uk/pub/data/weather/uk/climate/stationdata/sheffielddata.txt

 

June 2007 sticks out like a sore thumb, the month of the disastrous Sheffield floods. However, apart from that outlier, there is no pattern at all which suggests greater flooding potential or more extreme rainfall.

We keep being told that a warmer atmosphere can hold more moisture, hence more rainfall. But, as ever, the facts say something different.

via NOT A LOT OF PEOPLE KNOW THAT

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November 8, 2019 at 04:18PM