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The classic April day of memory has mild westerly winds, scudding clouds, blue sky, and the odd sharp shower. Driving this weather is the power of the sun drawing moist air off the cold sea (where temperatures are not much above their annual low point). It is this that causes cloud to bubble up after a sunny start and then fade away towards dusk.
But is this traditional pattern true anymore? (Or was it ever?) In recent years high pressure has been remarkably common this month, often bringing static dry weather which can be persistently sunny or cloudy depending on the wind direction. Temperatures even on sunny days may be tempered by easterly or northerly winds.
When one is sheltered from cold winds, the sun feels just right: warm and pleasant without being too hot, with temperatures typically in the mid to high teens centigrade, perhaps rising into the low twenties if one is lucky. Except possibly right at the end of the month, when shade and suntan cream can start to look welcome, it is generally still a delight to sit out in the sun even in the middle of the day. Breezes also mean the air stays fresh and the sky a deep blue.
By contrast, under cloud, particularly when airflows come off the North Sea, it can feel distinctly cool. Early in the month such weather can have you reaching for winter coats and pullovers, and even looking lingeringly at woolly hats. One still needs warm bedclothes, and the central heating may go back on again, though not for extended periods. Except very early in the month, nights usually avoid frost, however, with temperatures typically around 5 to 8 degrees.
Hotter years
If high pressure sets in during April, it can bring plentiful sunshine and summer-like heat. This seemed to be quite a trend in the first two decades of this century - for example in 2007, 2011 and 2020. All three years saw temperatures regularly getting into the low twenties, and Good Friday 2011 (22 April) saw the thermometer reaching 26 degrees. This was also a rare Easter (along with 2019 and 2022 - see below) when all four days were sunny.
In April 2020, which tragically coincided with the nationwide lockdown to combat the coronavirus (everyone required to stay at home apart from food shopping and one daily walk, run or cycle), there were 14 days of unbroken sun, seven more of sun and cloud, and 12 days when the temperature got into the twenties. There was brief rain on the 6th and 12th (the latter being Easter Sunday), but the month then ended with three days of cloud, quite substantial rain and much cooler temperatures.
In 2007 the first three weeks were completely dry and even when westerlies returned from 23 to 27 April there were only a few scattered and very short showers. Following on from a very warm January to March, this this seemed to suggest a hot summer was in store. But in fact the rest of the spring and summer in fact turned out to be unusually cool and rainy.
In 2011 lows in the first five days produced one day of rain and there were a few spots on 11 April, after which the weather remained cool and cloudy for another three days. Otherwise hot sun predominated, producing some isolated thundery showers to the south of London on the 23rd and 29th, but no rain north of the Thames. Only in the last few days of the month did easterly winds take the edge off the temperatures.
Other Aprils started unseasonably cold but soon warmed up. In 2013, following a bitterly cold March of east winds and grey skies, the 4th saw snow across the south east, which settled in Kent and Sussex. But the clouds also started to break up, and in the second week westerlies finally moved daytime temperatures into double digits and night time temperatures above freezing, raising them to 7-8 degrees by the 11th. On Sunday 14 temperatures surged to 22 degrees and winter was finally banished. The rest of the month was sunny, albeit alternating between temperatures in the mid to high teens, and others of just 10-13 degrees. In all the month saw 13 days and 10 with substantial amounts of sun.
In 2018 there was a static low to the west or south west for the first half of the month, with the weather quite cloudy but with sunny days on the 5th and 14th which brought welcome warmth (up to 18 degrees on the 14th) after a cold March. High pressure from the continent then set in from 16 to 22 April, with unbroken sunshine from 18 to 22 April and temperatures in the mid twenties, rising to 29 degrees on the 19th and 27 degrees on the 20th. The month finished on a fairly cool, cloudy and wet note, however, with temperatures generally in the mid teens, but no more than 8 degrees on the last three days of the month.
In 2008 highs to the south west and over Greenland brought north winds and 5 inches (12 cm) of snow overnight on the 6 April, a Sunday. It had melted by the afternoon but the following day also brought some snow overnight. However, by the 9th daytime temperatures were up to 14 degrees - warm enough to walk in shirtsleeves in the sunshine.
When the chill winds blow
A more common pattern for April in recent years, however, has been for high pressure to bring sunshine with a cool breeze that takes the edge off temperatures. 2022, 2021, 2019, 2017, 2016, 2014 and 2010 all had periods like this.
In 2022 and 2021, for example, winds were almost always northerly or easterly due to high pressure. In 2021 this kept temperatures down to 8-11 degrees in the first half and only 16 degrees at best in the second half (apart from one foray up to 18 degrees on the 19th). In 2022 the 10th to 21st - usefully straddling Easter, which was from the 15th to the 18th - were largely sunny, with temperatures in the high teens, or even as high as 22 degrees on Good Friday. At the end of the month the high settled over the UK, however, and the last eight days saw largely cool and grey conditions.
Both years also saw frosty nights - throughout the month in 2021, with night time temperatures as low as minus 3 in the first half, and still only 2 degrees on the 30th, and even some snow flurries on the 5th and 11th in London. In 2022 there were dustings of snow in Kent and Essex on the 1st - quite a shock after the warm sunny weather in the second half of March. Apart from these snow flurries, the month was almost entirely dry in 2021, while in 2022 the last eighteen days were.
In 2019 the first half of the month was mainly cool and cloudy due to a slow moving low in the first week which gave way to a Scandinavian high in the second. This brought winds from the east which kept temperatures pegged to the 9-12 degree range, with night time temperatures getting down to zero on the 3rd and 11th to 14th. Then in the third week the high shifted slightly, bringing air up from the south east and almost unbroken sunshine. Temperatures rose steadily and were 24 degrees over the entire Easter weekend, which was hot and sunny apart from some high cloud on the morning of Easter Monday. A slow moving low then moved in for the last week of the month, returning conditions to cool and cloudy. The second and third weeks were entirely dry, but there was enough rain in the first and fourth week to keep the countryside lush and green.
2017 saw high pressure in charge until the last three days of the month: centred to the south west, it brought plenty of sunny weather - nine full sun days and 14 days of sun and cloud - and no rain to speak of apart from very small amounts later on the 14th and 16th (inevitably Good Friday and Easter Sunday). A north west wind kept temperatures pegged to the mid teens. Night time temperatures were around 5-6 degrees but dipped to zero on the 18th and 19th, and again from the 25th to 27th, when the high moved west, bringing in north winds: it was also chilly by day on these three days with highs of around 11 degrees. In the last three days of the month low pressure edged south, bringing some rain later on the 30th - much needed, though the countryside had just about avoided tipping into drought due to reasonable rainfall in March. Early May also brought further showers.
In 2016 the month started with high pressure but with showers mixed in and unexceptional temperatures of 13 degrees. Three sunny days from the 12th to the 14th, when temperatures got as high as 17 degrees, seem to herald the start of more normal April conditions, but on the 18th high pressure then set in to the west bringing cool easterly winds, albeit with reasonable amounts of sunshine. Night time temperatures dipped to the low single digits. On the 23rd the same high made the winds turn northerly, bringing a wintry blast of air with daytime highs of just 8 to 9 degrees, and night times down to zero. With cloudy skies it felt more like February than late April. Only on the 30th did the north wind abate and temperatures edged up to 12 degrees.
2014 was fairly benign with 9 sunny days and good amounts of sun on 11 others. There was high pressure from the 1st to the 3rd and 8th to the 18th, the latter producing a two week drought, though with moderate rain before and after it. Temperatures also remained moderate - 13-16 degrees even on sunny days, with just a handful excursions into the high teens (though night time temperatures were dipping into the low single digits as late as the 20th). Easter, from the 18th to the 21st, was pleasantly sunny apart from a wet Easter Day.
2010 saw high pressure set in from the 8th onwards after a wet Easter. However, though the rest of the month saw plenty of sunshine, a cool north easterly wind kept temperatures down in the low teens until the 23rd, after which they soared up to 21 degrees. Rain was welcome when it finally arrived on the evening of the 29th, and the same was true in 2003, when rain came mid month after a dry March and sunny start to April. The rest of the month then alternated rain with sunny days.
In 2015 high pressure set in on late on the afternoon of Easter Sunday, 5 April, after a cold grey start to the Easter weekend. The weather was then largely sunny until the 23rd, with temperatures in the high teens, though at first tempered by a cool easterly breeze. On 14 to 15 April the wind turned southerly, however, and temperatures on the 15th rose to 25 degrees, the hottest April day since 2011. In the last five days of the month westerly lows set in, bringing welcome rain.
Particularly gloomy years
2024 was a particularly gloomy and grey April. The first ten days were cool and largely cloudy, with winds from the west. Then, when high pressure built in from the 15th to the 25th, it was centred to the west of the UK, bringing cold north or north east winds and a lot of cloud to the south east. Temperatures rose no higher than 12 degrees, except on the 18th when a rare sunny day allowed them to rise to 14 degrees. Night times were often in the low single digits. These low temperatures were all the more surprising after a very mild February and March that had brought on many signs of spring earlier than usual, and were also rather depressing, given that February and March had also been very cloudy. Only in the last two days of the month did the cold relent, producing two warm and sunny days, albeit with a stiff southerly breeze.
In 2012 late March saw hot dry weather and temperatures that peaked at 23 degrees on 30 March. But temperatures then dropped to 11 degrees on 1 April and a 16 day drought ended on 3 April, the Tuesday before Easter. The entire rest of the month was then characterised by very heavy showers and temperatures in the 9 to 13 degree range (at times down to 3 or 4 degrees at night), though most days had some sunny periods too. In all the month saw more than twice its normal rainfall, a fact that did not stop official drought warnings after a second dry winter. These soon looked silly, given that May, June and the first half of July went on to be very wet.
In April 2023 there was also double the usual amount of rain in parts of the south east, following on from a similarly wet March. The weather was mixed, with lows tussling with Scandinavian highs throughout the month, and neither staying in charge for long. The highs brought some welcome sunny and part sunny days after a March that had been lacking in either, but also easterly winds that made the mid teen temperatures seem a bit grudging. Rain was well scattered throughout the month, with 14 days seeing some.
Goodbye to mud
Paths can still turn muddy if it rains in April, but they dry increasingly rapidly - within an hour or two after a light shower, but potentially in a day or two after heavier rain. Patches of deeper mud do still linger in hollows and depths of woods, but even they are drying out, and grass is no longer squelchy underfoot. Exceptions to this include 2012 when cool temperatures and twice the normal rainfall left the paths at the end of the month as muddy as in the depths of winter, and 2023 when they were only just starting to dry significantly at the very end of the month. In 2014 there was plenty of mud still in the first week but it dried gradually thereafter despite wintry weather at the end of the month.
One stops thinking about what time it gets dark, although lighting up time in fact advances from 7.35pm to 8.20pm during the month, meaning that by its end it is light till nearly 9pm. The longer days mean that one can once more get up late on Sunday, dawdle around and then suddenly decide to go out, and still have time for a good long time out in the countryside.
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© Peter Conway 2006-2024 • All Rights Reserved
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