Even colder!

The Arctic blast continued on Friday with the thermometer not getting above 8.2C at 16.30, which was 6C below the 38-year average.

The thermometer dropped like a stone late evening to reach a minimum of -3.8C at 04.55 on Saturday. Not the coldest April night as in 2013 the thermometer dropped to -5.1C

Saturday brought muted sunshine to start the day, with the thermometer reading -1.9C at 08.00, but by 08.10 was beginning to increase in strength.

March 2022 Review

The first week was dominated by a very slow moving weather front that took two days to crawl eastwards before deciding to return westwards. This produced a week of cloudy conditions and cool temperatures by day, some 2C or 3C below average. The wind on several days came from the east and northeast producing a wind chill so that it felt much colder outside than indicated on a thermometer.

However, a touch of early spring arrived on a southerly airstream on the 8th that brought a warm air with temperatures by day rising above average.

It is best to forget the atrocious weather on the 16th when it rained continuously for over twelve hours producing 16.4mm of precipitation making it the wettest day since 21st October.

Storm Cecilia over the North Africa meant Saharan dust made its way to the south of the UK with a light covering on the 17th/18th. Barometric pressure rose considerably during this period with a peak pressure of 1043.7mb bringing much welcome sunshine.

High pressure began to build from the 17th as an intense and very large anticyclone settled close to or over the UK with a peak pressure of 1043.7mb on the 18th. The high pressure was maintained for 12 days. This settled period brought many days with wall-to-wall sunshine, dry days and soaring temperatures. The warmest day occurred on the 23rd with a maximum of 18.9C being the warmest day since 7th October and some 8.4C above my 38-year average.

A significant change began on the 29th when we lost the influence of the anticyclone. As a result the temperatures by day began to drop and cloud obliterated all chance of sunshine. The wind backed from the east to northeast and later to north.

The Arctic blast meant the thermometer struggled to reach 7.2C on the 31st being 3.3C below the 38-year average. During the day eight snow showers were observed, light in the morning but heavier in the afternoon. With the temperature a degree of two above freezing no snow remained on the ground.

The average temperature for March was 1C above the average with the maximum of 1.92C above average and the minimum almost exactly average.

There were 22 dry days during the month compared to the average of 16 and 6 wet days (rainfall equal or greater than 1mm) when the average is 11. The wettest day occurred on the 16th with 16.4mm. The monthly total of 43.6mm was 74% of the long-term average or 15.6mm below.

The rainfall that replenishes the aquifers is generally taken from mid-October to mid-March when rainfall percolates through the soil rather than evaporating into the atmosphere when temperatures are higher. The rainfall for this recent period was 290mm being just 71% of the long-term average or 122mm below.

The recent anticyclone that lingered over or close to the UK produced an average barometric pressure 8mb above the long-term average.

The diurnal range of temperatures is the variation between night and day. The figure for March has shown an increasing trend from 15C in the late 1980’s to 18C in recent years.

Back in 2020 I was one of the 16,000+ volunteers who responded to the challenge of digitising 5.2 million historical meteorological observations in just 16 days. This was a laborious but very worthwhile exercise. Ahead of the two-year anniversary of the project launch, on Saturday 26 March, the records were made publicly available in the official Met Office national record, extending it back 26 years to 1836.

Record-breaking Victorian weather has been revealed after millions of archived rainfall records dating back nearly 200 years were rescued.

The Rainfall Rescue project was launched by the University of Reading in March 2020 and offered members of the public a way of distracting themselves from the pandemic by digitally transcribing 130 years’ worth of handwritten rainfall observations from the Met Office archives.

The volunteers’ efforts have revealed some new records for extreme dry and wet months across the UK, as well as providing more context around recent changes in rainfall due to human-caused climate change.

Professor Ed Hawkins, a climate scientist at the University of Reading and Rainfall Rescue project lead, said: “I am still blown away by the response this project got from the public. Transcribing the records required around 100 million keystrokes, yet what I thought would take several months was completed in a matter of days”.

“Thanks to the hard work of the volunteers, we now have detailed accounts of the amount of rain that fell, back to 1836, as seen through the eyes of other dedicated volunteers from several generations ago. To put that in context, 1836 was the year Charles Darwin returned to the UK on the Beagle with Vice-Admiral Robert Fitzroy, and a year before Queen Victoria took to the throne”.

“As well as being a fascinating glimpse into the past, the new data allows a longer and more detailed picture of variations in monthly rainfall, which will aid new scientific research two centuries on. It increases our understanding of weather extremes and flood risk across the UK and Ireland, and helps us better understand the long-term trends towards the dramatic changes we’re seeing today.”

Dr Mark McCarthy, head of the Met Office’s National Climate Information Centre, said: “The UK rainfall record is notoriously variable, with extremes of weather presenting us with drought and floods. The more we can shine a light into the earlier chapters and extremes within the rainfall record, the better we are able to understand the risks presented to us by climate change and future extreme weather events.”