Why has April been so dry?

‘April showers’ have been in short supply this month for the UK, but just how dry has it been and why?

April 2022 has been predominantly settled so far. High-pressure has influenced the weather for much of the month, blocking rain-bearing Atlantic frontal systems and killing off any showers, though its effects have not been spread evenly. Low-pressure systems brought some wet days early on, especially across Scotland and Northern Ireland.

Dr Mark McCarthy of the National Climate Information Centre said: “What we’ve seen this month is a long period of time with the UK under the influence of high pressure, bringing calm and settled weather, especially in the south.

“Early in the month, the Azores High dominated the weather in the south, with low-pressure systems continuing to make some progress in northern areas. Later in the month high-pressure remained dominant, but this time centred more towards Scandinavia or Iceland, and this week over the UK itself. What this adds up to is a dry theme for the month, with scattered showers making limited impacts in northern areas.”

April's rainfall between 1 April and 28 April, compared to the meteorological average for the month. The map shows the UK has been predominantly dry in April 2022, except the far north of Scotland.
April’s rainfall between 1 April and 28 April, compared to the meteorological average for the month.

With a couple of days left of April, it has been a dry month across all regions of the UK, although most pronounced in the south. Up to 28 April, which is the latest provisional data that is available, you’d expect to have seen 93% of the average rainfall within the month, but currently for the UK, it’s at just 61% (43.7mm). Much of southern and eastern England has so far received only around a third of the monthly average rainfall, with a few locations in eastern England less than a fifth of normal.

England has so far seen 41% of its average (23.2mm), Wales 46% (40.7mm), Scotland 82% (76.4mm) and Northern Ireland 78% (57.9mm). The only areas that have been wetter than average are to be found in the north of Scotland, although the west of Northern Ireland has also had near-average rainfall.

Historically speaking, the dryness seen so far in April isn’t set to break any records and has not been as dry as April 2021, especially with some rain showers expected before the end of the month. You’d have to go back to 1842 to find the driest April on record, when an average of just 11.3mm of rain fell.

This April’s dryness continues a marked run of dry Aprils in recent years, with an average of just 20.6mm of rain falling in 2021, and 30mm in 2020. April 2019 saw similar levels of dryness to this year, with an average of 48.6mm falling in the month.

There is still some room for manoeuvre in the rainfall statistics, with some showers expected through the weekend.

Near-average picture elsewhere

The full statistics for April’s weather will be published on 3 May, but the indications up to 28 April suggest a near-average picture for much of the other national statistics for the UK.

Average maximum temperatures for the month so far stands at 12.5C, which is 0.5C above average. Minimum temperatures have been fairly close to average for the UK, standing at 3.6C, which is 0.2C lower than the average. There were some notably cold nights early in the month, with a hard frost on 3 April across southern England as temperatures fell to -4.9C at Wisley, Surrey and at Yeovilton, Somerset.

Sunshine levels are around what you’d expect for this time of the month, with an average of 153 hours so far (98% of the average for the whole month). Compared to average, the brighter areas have been found in the east, despite some recent cloud and fog, while northern areas of Scotland have been lagging slightly behind their average sunshine figures.

The full month’s weather and climate statistics will be released on 3 May.

Averages are determined by the 1991-2020 meteorological averaging period.

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