Rain in Oxford
Rain in Oxford
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Wettest January for 250 years, say University weather observers

Weather observers at the University of Oxford have confirmed that January 2014 was the wettest since their records began in the 1760s.

The University's Radcliffe Meteorological Station recorded total monthly rainfall for January as 146.9mm. This overtakes the previous high of 138.7mm recorded in January 1852.

This January's total rainfall is almost three times what would be expected, based on the average of January rainfall records for the last 247 years. The average for January has been 52.5mm since the station's records began. 

Dr Ian Ashpole, Radcliffe Meteorological Observer based in the University's School of Geography and the Environment, said: 'This January has had a very high number of "very wet" days rather than a few "monster" ones. People who live in the Oxford area endured consistently wet weather all January this year, with only one rain-free day.'

The Radcliffe Meteorological Station is located at the University's Green Templeton College. Since its observers began recording rainfall, only 14 out of nearly 250 Januarys have had more than 100mm of rain. As well as being wet, this January was also the 15th warmest on record, with an average of 6.24 degrees Celsius as compared with the usual January average of 3.8 degrees Celsius. 

The records show that this January was the wettest ever of any of the three winter months (December to February), beating the previous high of 143.3mm in December 1914. The most recent December and January combined total of 244.6mm of rainfall was also higher than for any other December–January period recorded by the Observatory.

In the 45 days following 18 December, more rain was recorded at the Radcliffe than for any other 45-day winter period in its history, with total rainfall at 231.3mm. This is way ahead of the next highest total of 209.4mm from 1 December 1914 to 14 January 1915, according to records of nearly 9,000 such periods.

January 2014 had 23 days with 2mm or higher rainfall in a day; 14 days with more than 5mm of rain recorded; and four days with more than 10mm of rainfall. It rained every day apart from 11 January. The five previous wettest Januarys were in 1852, with 138.7mm; 1995, with 131.4mm; 1948, with 127.3mm; 1877, with 115.1mm; and 1939, with 112.8mm of rainfall recorded.

The Radcliffe Meteorological Station at Oxford University has the longest series of temperature and rainfall records for any one site in Britain. The records are continuous from January 1815, with irregular observations of rainfall, cloud and temperature from 1767.