Coldest January since 2010, but not exceptional by historical standards

1 Feb 2021 04:07 PM

January, with an average temperature of 2.2 °C, has been the coldest January across the UK since 2010. In that year the average UK January temperature was 0.9 °C; the coldest January on record was 1963 with a mean temperature of -1.9 °C. It has also been the coldest calendar month since March 2013 which also recorded an average temperature of 2.2 °C.

Dr Mark McCarthy is the head of the Met Office’s National Climate Information Centre (NCIC). He said: “January 2021 has been dominated by colder-than-average weather with only brief milder interludes, but what does this cold winter mean in the context of climate change and a warming planet? Well, a winter month as cold or colder than January 2021 used to occur in approximately seven out of ten winters through the 20th Century. In more recent decades this has dropped to around three in ten. So although we are still subject to cold weather in winter, these cold spells tend not to be as severe or as frequent as in the past.”

  Maximum temperature    Minimum temperature  
Provisional January figures Actual °C Difference from Jan average °C Actual °C Difference from Jan average °C
UK 4.9 -1.5 -0.5 -1.4
England 5.7 -1.2 0.2 -1.1
Wales 5.9 -0.9 0.6 -0.9
Scotland 3.1 -2.1 -2.1 -2.1
Northern Ireland 5.8 -1.3 0.1 -1.3


Figure 1: Mean temperature across the UK during January 2021

A recently published study by Met Office scientists has also shown that the likelihood of experiencing extreme high winter temperatures, such as those in February 2019, has increased substantially. Mark added: “Taken together the evidence from recent UK winters is consistent with the overall effect of climate change leading to milder winters, less frequent cold extremes, and higher winter temperature records for the UK.”

The Met Office temperature series dates back to 1884, and last month struggles to get into the 30 coldest UK Januarys.

The coldest part of the UK relative to normal was Scotland with the average January temperature recording 0.6 °C. Tim Legg of the NCIC added: “A strong northerly flow was a main driver in bringing Scotland’s relatively low temperatures, but although they were the lowest on average since 2010, the northerly flow also brought substantial sunshine to Scotland for the time of year, marking a distinct contrast with England and Wales, which saw much less by comparison.”

  Sunshine  
Provisional January figures Actual sunshine in hours % of the January average   
UK 44.7 95
England 42.5 78
Wales 34.4 71
Scotland 48.6 136
Northern Ireland 57.5 129


Figure 2: Sunshine duration across the UK during January 2021

With 45.7 hours of sunshine on average, January 2021 saw Scotland experiencing its fourth sunniest January since records began in 1919. By comparison south east and central southern England experienced on average 35 hours of actual sunshine during the month, which is about 60% of the sunshine recorded during a typical January.

Tim Legg said: “The differences in sunshine figures between the north and south of the UK during January are quite marked. During winter day length is longer in southern England than in Scotland, and that is usually reflected in the sunshine figures. But this January we have seen a marked difference with the hours of actual sunshine increasing from south to north.”

Precipitation

The combined totals of rain and snow across the UK reveal that January 2021 wasn’t an exceptional month for the UK overall. But the UK figure does not represent the complete picture. Mark McCarthy added: “Several areas of England and Scotland saw more than double the amount of rainfall for a typical January, and Loftus in North Yorkshire had more than three times its normal January rainfall. Elsewhere East Lothian in Scotland and several East Midlands and north-western areas of England recorded double their average precipitation.”

The wettest areas by amount of rain were in north Wales and north-west England, with in excess of 200 mm through the month, a significant proportion of which was rainfall associated with storm Christoph from 18th to 20th.

  Rainfall  
Provisional January figures Actual rainfall % of the January average   
UK 136.6mm 113
England 124.0mm 150
Wales 208.4mm 133
Scotland 141.0mm 80
Northern Ireland 119.1mm 102


Figure 3: Precipitation (including rain and snow) across the UK during January 2021