Northern Ireland has had its third hottest summer on record, and Scotland its fourth.

The summer of 2021 has been a season of contrasting fortunes across the UK, with the north and west of the UK experiencing a warmer, drier and sunnier season compared to average while parts of the south east have been duller and wetter than average.

Northern Ireland experienced its third warmest summer on record (15.06°C) and also recorded its highest temperature on record with 31.3°C recorded on 21 July at Castlederg in Tyrone. Some regions of Scotland*, including the City of Glasgow, where COP 26 will be held in November, had their hottest summer in records back to 1884.

The UK as a whole has had its ninth hottest summer on record, with an average of 15.28°C. This is the hottest summer for the UK since 2018. While 2019 and 2020 both experienced extreme heatwave events, in contrast 2021 temperatures reached a peak of 32.2°C at Heathrow on 20th July.  However, relatively high temperatures in June and July, coupled with persistently high minimum temperatures and relative warmth across the north of the UK have pushed this year up the rankings.

Map showing mean temperature across the UK for Summer 2021

As outlined in our recent blog, the conditions have not been consistent across the UK. London, East Sussex and Hampshire receiving 140% to 150% of average summer rainfall and the Isle of Wight exceeding 200%. However, much of the UK saw below average rainfall and when averaged out across the whole nation, the UK received 75% of its average rainfall (181.2mm).

The south-east corner of the UK also saw less sunshine than the long-term average. The brightest and driest conditions were in the north west of the UK. When averaged out across the whole nation, the UK received 99% of its average summer sunshine (501.6 hours).

Maps showing rainfall and sunshine across the UK for Summer 2021

Head of the Met Office’s National Climate Information Centre, Dr Mark McCarthy, said: “Summer 2021 will be remembered very differently depending on where you are in the UK, with record-breaking warm conditions in parts of western Scotland and Northern Ireland, while in the south and east it’s been much duller and wetter. There have been several notable weather events through the summer, including a new temperature record for Northern Ireland and Storm Evert which brought strong winds and heavy rain across England and Wales and extreme rainfall in the south east.”

Graphic showing climate statistics for the past five summers in the UK


The statistics for August may explain why some may feel that the summer has been dull and cool. The final month of summer has been much closer to the average temperature, with the UK just 0.1°C above the long-term average. As with the full season, the August temperatures were higher than average in the north west, with cooler than average temperatures in the south and east. 

It is quite unusual for the highest temperature of August to occur in Scotland, but the suppressed temperatures in the south of England mean that 27.2°C recorded at Tyndrum on 25 August is the highest temperature recorded in the UK during August 2021, and is the lowest such value since August 2010.

Map showing mean temperature across the UK for August 2021

Most of the UK has recorded lower than average rainfall, with the exception of Northern Ireland (110%, 106.8mm) and parts of eastern Scotland, with the UK receiving 73% (65.4mm) of its average. Many regions, particularly along the east of the UK, have experienced a higher than average number of rainfall days (where more than 0.2mm has been recorded), which coupled with plenty of cloud and reduced sunshine may have contributed to a perception of it being wetter.

Maps showing rainfall anomaly and rain days across the UK for August 2021Map showing sunshine hours anomaly across the UK for August 2021

* Clackmannan, Dunbartonshire, Perth and Kinross, Renfrewshire, Stirling and Falkirk, City of Glasgow and West Lothian.