An historical perspective of the climate statistics for Coventry during October 2017

Temperature

There has been a 1.3°C increase in average October temperatures since 2000 in Coventry. The 2001 to 2015 October average was 11.5C compared to 10.2C average from 1991 to 2000.

So with this warming in mind, it is no surprise to find that October 2017 (mean 12.7C) continued this trend, and has become the fifth October in succession to record mean temperatures higher than the 1981-2010 30 year Bablake average for the month.

October 2017 has been the warmest October in Coventry since 2011 (12.8C), with only six October months warmer than this year in city records dating back to 1892, namely 1921, 1995, 2001, 2005, 2006 and 2011.

In the first ten months of 2017, the average temperature has been 11.9C in Coventry, the highest mean January to October spell in the city since 2014 (12.0C), though only this period and that in 1990 are the only such ten-month spells warmer than 2017 in the past 125 years.

We had our first autumn grass frost of the season on the 28th October, the latest first ground frost in the city since 2006 (1st November).

  • 30th    the coldest night of the month was the coldest October night in Coventry since 2012.

Rainfall

Last year, October 2016 was the driest (16.0mm) October in Coventry since 1978 (6.0mm).

So this year, it was wetter (34.8mm) than a year ago, but with just 51% of average October rainfall.

52% of the monthly rainfall total fell on just one, the 19th October (18.0mm); this was the wettest October day in Coventry since 2013 (25.2mm).

The driest decade in our records (dating back to 1870) for October, was the 1970’s (44.3mm), though the 21st century has been much wetter with the October rainfall average this decade being 77.4mm from 2011 to 2015. Just for the record, this has been the wettest decade so far since the wettest decade on record from 1891-1900 (74.3mm).

So, with this wet theme in mind, it is strange to report that of late, only two October months have recorded rainfall totals above the 30-year Coventry average (67.8mm) in the past 11 years (2013 & 2014).

Sunshine

Although there was a 59% increase in sunshine levels between 1894 and 1999, the early 21st century has seen a fall in sunshine totals in Coventry back to the levels more common in the 1970s, when the Clean Air Acts were introduced to rid the atmosphere of smoke pollution and smog.

By the 1990’s we were averaging 113.9hr of sun during October in Coventry, though since the Millennium, this has fallen to 97.0hr, a decrease of 15%, just at a time when the month has been getting warmer.

October 2017 has been our dullest October in Coventry (75.6hr) since 2013 (71.8hr) with just 72% of average monthly sunshine. This is the sixth October in succession to record less sunshine that the 30-year Coventry average.

In the first ten months of 2017, we have recorded just 1301.0 hours of sunshine (9% below average); this is the lowest such total since 2012 (1298.7hr), the only such ten-month period duller since the Millennium. Only four January to October periods have recorded less sunshine since 1971 (1978 1981 1987 2012).

27th    The sunniest day of the month recorded just 6.9 hours of sunshine, the lowest such value since 2004 (6.5hr) and 2000 (5.8hr).        .