UK 2020 summary

A very wet and at times stormy winter (5th wettest on record for UK back to 1862), driven by an unusually persistent strong stratospheric polar vortex, which included the wettest February on record in the UK since 1862 resulting in severe floods especially across Yorkshire and along the Severn. Fortunately high pressure dominated the scene from the second half of March onwards with Spring 2020 being among the driest on record - it was also exceptionally sunny smashing previous records for all regions. The spring pattern changed as soon as the meteorological summer came along with low pressure setting up over the UK during most of the summer. It was an often thundery summer, one of the most thundery summers in past 30 years with notable thunderstorm outbreaks in late June and mid-August. Early to mid August became exceptionally hot in the south of the UK but it ended very differently, cool and often stormy. Much of September was very warm and became hot for a time mid-month but the last week or so was greatly cooler with early frosts in the north whilst the south and east were very unsettled at times leading into an exceptional wet October including the UK's wettest day on record. A mild but dry November ended the autumn on a benign note before a changeable December to conclude quite an infamous year in many aspects. 

January. One of the mildest Januaries of recent times with frequent southwesterly influence during the first half but the second half tended to be cooler and included an exceptional intense anticyclone around the 19th/20th which brought record breaking high mean sea level pressure to some. London had its highest air pressure in over 300 years with Heathrow observing 1049.6mb on the 19th. The highest overall was 1050.5mb at Mumbles (Swansea) on the 20th resulting in the highest air pressure in England & Wales since January 1932 when an air pressure of 1050mb was last reached here. The Central England Temperature (CET) for January was 6.4°C, mildest since 2007. The UK mean temperature was similar with 5.6°C, mildest since 2007 and the 5th mildest on record since 1884. The maximum temperature was 15.5°C at Achfary (Sutherland) on the 7th, a new date record. The minimum temperature was -7.9°C at Braemar (Highland) on the 10th, the highest absolute January minimum since 1998. Rainfall for the country as a whole was bang on average with the second half tending to be drier than the first. Northern Ireland had the driest conditions relative to average but western Scotland was wet. Sunshine was overall slightly below average with the northwest being particularly dull but northeast England tended to be sunnier. One named system, Storm Brendan, on the 13th gave a max. wind gust of 87 mph at South Uist (Western Isles).

February. A truly exceptional wet and stormy month with a very active North Atlantic jet stream. Rainfall was well above average for all with the UK recording 209.1mm (237% of average), more than 10mm wetter than the previous record of 193.4mm in February 1990. Some had up to 400% of their average February rainfall. It was the 5th wettest of any month for the UK back to 1862 behind only October 1903 (227.4mm), December 2015 (217.4mm), November 2009 (215.1mm) and December 1929 (212.9mm). Even for the long-term England & Wales Precipitation (with monthly records back to 1766), it was the wettest February on record with 169.6mm beating 158.6mm all the way back in February 1833. It was also generally a very mild month though less so relative to normal in the north where polar maritime airmasses from northwesterlies kept conditions somewhat cooler. However, even in the mild regions, it tended to not be as mild as February 2019. The CET was 6.3°C compared to 6.7°C in February 2019 but still one of the milder Februaries of recent times. The maximum temperature of February was 16.0°C at East Malling (Kent) on the 16th, quite anti-climactic compared to February 2019's record breaking warm spell, whilst the lowest was -10.2°C at Braemar (Highland) on the 13th. Unlike January which was largely snowless besides some in the final week, February brought several colder outbreaks from the northwest (which brought a relief to Scottish ski resorts after a very poor winter up to that point) particularly during the 10th-12th following on from Storm Ciara on the 9th which brought the highest wind gust of 97 mph to the Needles (Isle of Wight) on the 9th. There were three named storms during February, Storm Ciara (9th-11th), Storm Dennis (16th) and Storm Jorge (29th). The latter was named by the Spanish Met. Both Ciara and Dennis brought very high daily totals to parts of the country, most notably Dennis which resulted in a rare red rainfall warning (the first of any kind of red warning since Storm Emma in March 2018) being issued by the UK Met Office for South Wales. More than 160mm (equivalent to 6.3 inches) of rain was recorded in a 48-hour period starting at midday on 14 February at Maerdy (Rhondda). The town of Pontypridd (Rhondda) was badly impacted by the rain with severe floods and the River Taff near Cardiff reached its highest level in recorded history. Pontypridd (Rhondda) houses were inundated by more than 1.5 m of water from the floods with residents having to be rescued from their upper floors. A major emergency was declared across the county. This all was not helped by the fact that the summer-autumn-winter period prior to February had been so wet already. 15th February was also the third wettest day on record for the UK in a national daily series since 1891.

March. As the saying goes, March comes in like a lion and out like a lamb. This would be the perfect description for March 2020 with the month divided into two halves. The first half was more unsettled and changeable continuing on from the wet summer to winter period but the second half was dominated by anticyclonic conditions. The high pressure was a sign that the weather turned its tables on the exceptional wet period since last summer. It was relatively dry overall with 78.0mm (82% of average) and the driest March since 2013 but this is merely a reflection of March's changeable nature recently than anything else. It was very sunny with the UK having its sunniest March in 8 years with 136.3 hrs (134% of average) though not one of the sunniest on record. In contrast to the winter, March had much closer to average temperatures with no big deviation. The maximum temperature was 19.4°C at Rhyl (Denbighshire) on the 24th and the lowest was -7.6°C at Aboyne (Aberdeenshire) on the 16th. There were no named storms during March. 

April. Plentiful high pressure over or near the UK with a mean easterly airflow. This meant for a very dry, sunny and warm April. Despite this though, it only just fits in with the top 10 driest Aprils for the UK since 1862 with 29.1mm and the driest since 2007. This was because some parts of the south actually had near normal or slightly above average rainfall including Wiltshire and Hampshire. This was mainly down to heavy falls in the last 4 days of the month and between the 17th-19th however whilst the rest of the month was dry as a bone. The 1st-6th and 11th-13th were slightly less settled too but not much rain. The CET for April 2020 was 10.4°C making it the joint 5th warmest on record since 1659 and warmest since 2011. Similarly, the UK with a mean temperature of 9.1°C had its 5th warmest April since 1884. The most notable thing about the month is probably the sunshine. For the UK, it was the sunniest April on record since 1929 with 224.5 hrs beating 211.9 hrs in April 2015. It was also the sunniest April on record for both England and Northern Ireland beating respective records set in 2015. The maximum temperature was 26.0°C at Treknow (Cornwall) on Good Friday (10th April). Strangely enough, this was nearly the exact same temperature recorded at the exact same location on Good Friday (19th April) 2019 which had 25.8°C at Treknow (Cornwall). The minimum temperature was -6.9°C at Braemar (Highland) on the 19th.

May. An extraordinary month with well below average rainfall, well above average sunshine and above average temperatures. It was the driest May on record over England in a series back to 1862. It was also the 2nd driest May on record in Wales back to 1862. For the UK as a whole, it was the driest May since 1991 with only 32.7mm (47% of average). Benson (Oxfordshire) had an entire month with no measurable rainfall whilst up to 10 official Met Office stations had recorded 1.0mm or less during May. In contrast, it was significantly wetter than average across parts of Scotland with Achnagart (Highland) measuring 226.4mm during May with 97.2mm of this falling in the 24-hour period ending at 0900 on the 23rd - its wettest May day in 51 years. The CET for May was 12.5°C (same as May 2016) so not a very warm month by any means; Mays 2017 and 2018 were warmer, but still solidly above average. This average hides the variability of the month however with a relatively cool first half outweighed by much warmer second half. The first half contained some notably cold nights including -6.6°C at Kinbrace (Sutherland) on the 3rd and -6.1°C at Katesbridge (Co. Down) on the 14th - the former was the lowest May temperature in the UK since 1997. The maximum temperature reached 28.2°C at Santon Downham (Norfolk) on the 20th, the highest for the UK so far this year but would be beaten later by 28.3°C at Cromdale (Moray) on the 29th. Like April, the most standout statistic of May 2020 was without a doubt sunshine. With 265.5 hrs of sunshine, it was the sunniest of any month on record for the UK beating the long-standing record of 264.9 hrs from June 1957. As you'd expect, it was the sunniest May on record too for the UK coming only 2 years after the 2nd sunniest May on record in 2018. It was the sunniest May on record for both England and Wales also beating records set in 2018 and 1948 respectively.

June. The Spring dry spell ended this month with June being very changeable, often windy and unsettled. Whilst it began and ended cool, it was relatively mild overall with a CET of 15.3°C. There was a brief period of hot weather on the 24th and 25th with the maximum reaching 33.4°C at Heathrow on the 25th although some recent Junes have seen higher maxima - a reflection of just how hot recent Junes have gotten during southerly airflows. It was also very thundery in nature which was a change on recent summer months, with notable thundery periods from 5th/6th, 13th-16th and again 25th-27th. Rainfall was 144% of average overall for the UK with isolated locations having their wettest June on record including Castlederg (Co. Tyrone) and Cardinham (Cornwall). For the country as a whole, it tended to be the wettest June in the UK since 2012. 212.8mm of rain fell at Honister Pass (Cumbria) in the 24-hour period ending at 0900 UTC on the 29th courtesy of a depression that passed to the northwest - a new UK daily rainfall record for June. Sunshine was close to average overall with 97% of average but with huge regional variations. Southeastern England and northern Scotland fared best for sunshine relative to average whilst the west was rather dull with some having their dullest June since 2012. Preceding March was sunnier than June for many. 

July. A relatively cool, dull and often unsettled month; the coolest July since 2015. Much of the month was dominated by northwesterly winds which fed in a lot of cloud from the North Atlantic and temperatures below average though nights held up due to the overcast skies. An extreme southerly plume occurred on the final day of the month with much of England in excess of 30°C on this day - in spite of what was looking like the first July since 2011 to fail to reach the mark. Heathrow's (Greater London) max of 37.8°C on 31 July 2020 made it the third hottest day on record in the UK behind 25 July 2019 and 10 August 2003. It was often changeable with a wet start but high pressure ridged in mid-month which settled down things somewhat, especially in the south where it wasn't an especially wet month. Despite this, the UK as a whole had 122% of its average July rainfall with southern Scotland and NW England being very wet - their wettest July since 2012. It was not a thundery month at all, one of the least thundery Julys of recent times. Sunshine was well below average for the north and west but close to average in the south giving the UK 88% of its July sunshine average overall. Northern Ireland had its dullest July since 1986 and second dullest on record (since 1929).

August. The warmest August since 2004 (CET of 17.6°C) with an extremely hot first half being offset to an extent by a very unsettled and cool second half with two named storms. The month started off unsettled with outbreaks of rain from the west and mostly cloudy conditions but pressure rose from the south and east by the 6th ushering in a very hot southerly airflow to southern regions of the UK where temperatures widely exceeded 30°C for at least a week and locally achieving 35°C in the southeast of England including 36.4°C at Heathrow (Greater London) and Kew Gardens (Greater London) on the 7th which is the highest August temperature in the UK since 2003. This was the 9th consecutive summer (JJA) month to achieve 33°C somewhere in the UK. Six consecutive days from 7th-12th August achieved 34°C somewhere in the UK - this was the only occasion since at least 1961 where 34°C was achieved somewhere in the UK for 6 consecutive days. At least 20 stations achieved temperatures of 32°C or more during these same 6 days - this is the first time such an occurrence has happened since 1st to 6th July 1976. This heat tended to be limited to the south with the north being much cooler. The heat was of a very volatile nature by the 10th with localised severe thunderstorms breaking out in what was probably the most thundery period for a long time with approximately 126,000 lightning strikes occurring over or around the UK and Ireland on 12th August. Hail of 2-3cm in diameter was reported in Snowdonia on the 10th and 2cm hail in Oxfordshire on the 11th along with wind gusts over 50 mph in the Gloucester area on the 12th. It became gradually cooler after the 13th with the weather turning more changeable but further thunderstorms broke out including in Norfolk on the 16th where a new UK daily rainfall record for August was set - 239.9mm fell at Wretham (Norfolk). It became stormy by the 19th with Storm Ellen pushing up from the southwest bringing wet and windy conditions. Storm Francis on the 25th brought further gales and very wet weather including the max wind gust for the month of 81 mph at Needles (Isle of Wight) on the 25th. On the whole, it was a wet August with 135% of average UK rainfall but with some variation due to thunderstorms and tended to be drier than August 2019. Sunshine was below average for most regions away from northwest Scotland and it was the dullest August since 2011 with 88% of average sunshine.

September. A slightly warmer than average month (CET of 13.9C - slightly cooler than September 2019 but not as cool as September 2018 for recent comparison) but with a warm first half and hot period mid-month offset by a much cooler final week. The start of the month was largely westerly with outbreaks of rain interspersed with brighter showery conditions. By the 12th, ridging advected north from the south with a southerly flow bringing increasingly warm air but heavy rain continued for a time in the far north. It became hot for a time by the 15th with 31.3°C achieved at Frittenden (Kent) - the highest September temperature and first September 30°C since 2016. This was the peak of the warmth as it cooled down somewhat the days following but it remained settled with high pressure in charge. It became unsettled from the 22nd with low pressure dropping down from the northwest and northerly winds circulating around the western flank of the low which meant much cooler conditions. Temperatures bottomed out at -5.0°C at Altnaharra (Sutherland) on the 24th and at Braemar (Aberdeenshire) on the 27th - this was the lowest September temperature for the UK since 1997. It was also the first time that 30°C and -5°C have occurred in the same September for 101 years, all the way back in 1919. It was stormy on the east coast of England on the 25th with Weybourne (Norfolk) and Donna Nook (Lincolnshire) observing max gusts of 67 mph. It was a drier and sunnier than average month for the UK with 77% of average rainfall - the driest September since 2015 and 117% of average sunshine - similar to September 2019.

October. A very unsettled month with well above average rainfall and well below average sunshine for the vast majority of places. Storm Alex at the start of the month, named by the Spanish and French Met agencies, brought widespread heavy rain from 2nd to 4th with 3rd in particular being a notably wet day - in fact it was the wettest day on record for the UK in a daily series since 1891 with a national average of 31.7mm beating the previous record of 29.8mm on 25th August 1986 during the remnants of hurricane Charley. 127.1mm of rain fell at Fettercairn (Kincardineshire) in the 24-hour period ending at 0900 GMT on the 4th. Rainfall was 142% of average for the UK - the wettest October since 2000 and the 5th wettest on record since 1862. Besides some more settled conditions mid-month from 14th to 18th, it stayed unsettled throughout October. It was the 8th wettest month on record in Greater London. It was the dullest October for the UK since 1982 with only 72% of average sunshine and 5th dullest on record since 1919. Storm Aiden brought a wet and windy Halloween to end the month into early November but was a fairly typical spell of stormy weather for the time of year on an active jet stream. The CET for October was 10.5°C which is near average whilst the absolute max only reached 19.1°C at Writtle (Essex) on the 8th with an air minimum temperature of -3.3°C at Tyndrum (Perthshire) on the 15th.

November. A generally very mild month with frequent southerly and southwesterly influence. The CET was 8.5°C which makes it one of the mildest Novembers since 1659 but not as mild as 2015, 2011 and 1994 - the latter of which remains the mildest November on record. For the UK, it was the 6th warmest November since 1884. Besides anticyclonic conditions around the 4th to 7th, the first few weeks of November were fairly unsettled whilst high pressure brought colder conditions with widespread patches of fog from the 26th to the 29th including the first frosts for some of the season. Despite the Atlantic influence, it was a relatively dry November with 84% of average rainfall for the UK but it was near or above normal in western Scotland, northwest England and Northern Ireland. Sunshine was slightly below average with 93% of average but with some regional variation - e.g. well below average over Northern Ireland and western Scotland but above average in northern Scotland and in East Anglia. The highest temperature of the month was 18.4°C on the 1st at Thornes Park (West Yorkshire) and Hawarden (Clwyd) whilst the lowest temperature was -6.1°C at Aboyne (Aberdeenshire) and Cromdale (Morayshire) on the 29th. 

December. Largely unsettled and rarely anticyclonic. The month began in its form with unsettled but increasingly cold weather as low pressure set up shop over the UK in combination with mid-Atlantic ridging which meant winds tended to be from the north. There was a mix of rain and sleet for most from time to time, particularly on the 4th with any snow tending to be over high ground. As wind speeds dropped by the 6th, patches of fog developed with freezing fog for some under slack and cold but cyclonic conditions. It became milder from the 8th while remaining unsettled and became stormy at times. This pattern continued up until Christmas Eve when another northerly toppler set in bringing flurries to eastern parts of the country. A deep depression, named Storm Bella, approached from the northwest on Boxing Day ushering in cold and unsettled weather for the remainder of 2020 and lying snow became increasingly prevalent for low levels by the New Year in what was going to be the most prolonged spell of colder than average conditions since early 2013 but there was a fair bit of rain and sleet too particularly on the coast as the air was not severely cold. Bella gave a max wind gust of 106 mph at Needles (Isle of Wight) on the 27th. As previously mentioned, there was plenty of rain during the month with 135% of average rainfall for the UK and the wettest December since 2015. Bella also gave the highest daily rainfall of the month with 109mm at Honister Pass (Cumbria) in the 24-hour period ending at 0900 GMT on the 27th. Sunshine was 93% of average and similarly to November, there was some regional variation with sunnier than normal anomalies in central southern England, the Midlands and East Anglia whilst it was very dull over most of Scotland and Wales. A max snow depth of 18cm was recorded at Loch Glascarnoch (Ross & Cromarty) on New Year's Eve. The highest temperature of the month was 14.9°C at Prestatyn (Clwyd) on the 18th and the lowest was -10.2°C at Dalwhinnie on the 30th which was the joint lowest temperature for the year - 2020 had the highest absolute air minimum temperature since 2014. 

Averages refer to 1981-2010.