April weather summary video and your photos

15 05 2013

Following on from the second coldest March on record, April was another cool month, with  temperatures below average everywhere. The provisional UK mean temperature was 6.3 °C, which is 1.1 °C below the 1981-2010 average, very similar to 2012 but otherwise the coldest April for the UK since 1989. Forecaster Helen talks through the weather we’ve seen this month in our video.

For a full written summary of the weather in April visit the climate section of our website.

Your weather pictures

Thank you for sharing your weather pictures with us on Twitter, here’s some of our favourites.





April drier and colder than average

2 05 2013

After the wettest April on record in 2012, provisional full-month Met Office figures show this April has been slightly drier than average in the UK.

Rainfall throughout the UK was 64 mm this year, compared to the 1981-2010 average of 72.7 mm. That’s considerably less than the 128 mm we saw last year.

There were big regional differences in April rainfall this year. Scotland saw 121.2 mm of rain which is above the 91.1 mm average and Northern Ireland saw 75.2mm, almost spot on the 75.0 mm average.

However, both England and Wales saw well below average rainfall. Wales had 50.3mm, compared to an average of 89.3mm, and England saw 30.4mm, compared to an average of 58.7 mm.

The month was characterised by generally cold and dry weather, following on from the theme set in March. Despite this, April registered as only slightly colder than average with a mean UK temperature of 6.3 °C, which is 1.1 °C below the 7.4 °C long-term average.

This is the same mean temperature as recorded in April 2012. To find a colder April than the last two years, you have to go back to 1989 – which saw a mean temperature of 5.5 °C.

Scotland saw the coldest temperatures compared to country specific averages, with a mean temperature of 4.8 °C, which is 1.3 °C below average – and is the same temperature as recorded in 1998.

The warmest day of the month was 25 April at Faversham in Kent when the temperature recorded was 23.1°C.

In terms of sunshine, Scotland was sunnier than the rest of the UK with hours of sunshine totalling 170.9, followed by Northern Ireland with 168.0, England at 167.7 and Wales at 162.7 hours.

This compares with only 127.9 hours of sunshine in April last year throughout the UK. The sunniest April in the last 10 years was 2007 with 203.5 hours.

Mean Temperature Sunshine hours Rainfall
Apr-13 Actual Diff to Avg Actual Diff to Avg Actual Diff to Avg
degC degC hours % mm %
UK 6.3 -1.1 168.4 114 64 88
England 7.2 -0.9 167.7 108 30.4 52
Wales 6.4 -1.2 162.7 105 50.3 56
Scotland 4.8 -1.3 170.9 127 121.2 133
N Ireland 6.5 -1.1 168 115 75.2 100




Warm but unsettled weekend ahead as cold eases grip on UK

10 04 2013

The UK is set to see some warmer temperatures this weekend as the colder than average weather seen so far this April eases its grip.

Temperatures have been steadily climbing since the exceptionally cold weather towards the start of the month, with today through to Friday set to see double-digit figures for many places.

On Saturday temperatures will be generally between 11 and 13 °C, feeling much milder than recent days. However, the weather will be wet, fairly windy and unsettled for many parts – with the best of any drier and brighter weather in the south and east.

Forecast chart for midday Saturday shows low pressure moving in from the Atlantic to bring mild but wet and windy weather for most of the country. High pressure still dominates in the south and east, bringing the best of any drier and brighter weather.

Forecast chart for midday Saturday shows low pressure moving in from the Atlantic to bring mild but wet and windy weather for most of the country. High pressure still dominates in the south and east, bringing the best of any drier and brighter weather.

Warmest day of the year so far

Sunday looks set to be the warmest day of 2013 so far, with temperatures expected to be widely in the mid-teens Celsius. While the weather will be slightly more settled than Saturday, many places will see cloudy and breezy conditions with a risk of some light showers.

Once again the south and east will see the best of the weather, with drier and brighter conditions and temperatures of 15-18 °C – with a possibility that some isolated spots could reach around 20 °C.

Leading in to next week temperatures look set to cool slightly, but remain around average for the time of year.

Jet stream shift brings milder weather

The reason for the shift away from the colder weather is the re-alignment of the jet stream, a band of fast moving westerly winds high up in the atmosphere which tends to guide Atlantic weather systems. It’s these weather systems that bring us the mild and unsettled weather we normally expect at this time of year.

During the prolonged cold conditions the jet stream tracked far to the south of the UK, guiding those mild weather systems towards the Mediterranean. The UK, meanwhile, saw an easterly flow – bringing in cold conditions from the cold winter climes of north-east Europe.

Now the jet stream has started to shift its track, moving north to a position more in line with what we’d expect at this time of year. This means we expect to see milder, but also more unsettled weather coming in from the Atlantic over the coming week or so.





April 2012 early statistics – above average rainfall

27 04 2012

These are early figures covering 1 – 25 of April and not full month statistics, so are therefore very likely to change. Especially regarding ranking. Full month figures will not be available until provisionally Wednesday 2 May.

Figures for 1 – 25 April show the month so far has seen well above average rainfall across the UK, with 97 mm of rain recorded – this is 139% of the long-term monthly average (1971-2000). The wettest April in the records dating back to 1910 was 2000 which saw 120.3 mm of rain.

Currently the month is the 9th wettest April for the UK in the records. However, it’s not possible to say where the month will end up in the records until all the figures are in at the end of the month – especially as we are expecting heavy rain on Sunday.

Some areas have seen significant rainfall amounts with some parts of the UK already having had more than double their monthly average. Some station records are also very likely to be broken.

Impact on drought

Looking at the England South area, which has been the focus of the current drought, this month is one of only three in the last two years which has seen significantly above average rainfall.

As can be seen from the chart below, the majority of other months during that time have seen below average rainfall.

Monthly rainfall anomalies for region England south for the last 3 years. 13 of the last 24 months have seen less than 75% of average rainfall, and 6 months have seen less than 50%. Only 2 months - June 2011 and August 2010, have been significantly wetter than average.

Trevor Bishop, Head of Water Resources at the Environment Agency, said: “it’s going to take more than a week or two of rain to undo the effects of nearly two years of below average rainfall.

“More rain now will really help us get through the summer, and is good for the environment, farmers and gardeners, but it’s very unlikely to be enough to recharge the groundwater.”

Duller and slightly cooler than average

Temperatures have been close to the average for the time of year, despite some cold nights towards the beginning of the month which brought frosts to many areas.

Sunshine hours have been slightly down on the average so far this month, with most parts of the country seeing only about two thirds to three quarters of the average expected in the month. However, this could improve during the final few days of April.

Why the unsettled weather this month?

The position of the jet stream has been one key contributing factor, but potentially not the only one. You can read more about this on our blog post.





Met Office in the Media: 19 April 2012

19 04 2012

The wet weather across parts of the UK at the moment has generated comments about how wet this April as a whole may pan out in the record books.  As we have said in blogs previously, it is just too early when we are still only mid month to make any assessment about how the month as a whole may compare to previous months in history.

Today the Daily Telegraph reported that the ‘the wet weather will continue to the end of this month, including floods and storms, according to the Met Office, potentially making it one of the wettest April’s on record.’  Although our outlook does suggest that the rather unsettled conditions are likely to continue through the rest of the month, we have not made any assessment on whether it is likely to be one of the wettest April’s on record.

Looking at the latest figures available, the UK has seen around 60% of its normal April rainfall, or 41.7mm up to the 15th of April.  At this point of the month we would normally expect about 50% of the months rainfall so rainfall amounts so far have not been far from what you could typically expect. On average, a typical April would see 69.6 mm or rain.

The Daily Express has today run with a headline that we are expecting the ‘Coldest May for 100 Years’.  This forecast has not come from the Met Office, but from an independent forecaster. Currently our 16 to 30 day forecast which takes in the first half of May says:

“The start of May looks likely to remain unsettled with a continuation of showers or longer spells of rain, although there should also be some drier and brighter interludes. Temperatures will generally be close to or slightly above the seasonal average. Later in the first week of May, conditions may turn more settled across southern England for a time, with a greater chance of some drier and sunnier weather than of late. Further north, it looks likely to stay unsettled with further rain at times, particularly across northwest England as well as northern and western parts of Scotland.”





Why are we getting thunder and lightning?

11 04 2012

With the weather in April being distinctly showery so far, what exactly causes this changeable weather and why do some showers give thunder and lightning?

 

Thunderstorms are normally associated with convective clouds which form from rising air warmed by the Sun. At this time of year we have longer days and therefore more heat reaches the Earth’s surface giving a greater chance for convective clouds to form. The air is continuously moving within the cloud in a very disorderly fashion, allowing the cloud to grow and water droplets or ice crystals to form. Given enough time and growth, the cloud may develop into a Cumulonimbus cloud and give quite heavy bursts of rain or hail for short periods of time, and possibly thunder and lightning.

Hail forms when ice crystals or frozen raindrops within the cloud get thrown about with the rapidly circulating air. As they ascend they grow as water freezes on the surface of the droplet or crystal. Eventually the droplets will become too heavy to be supported by the updraughts of air and they fall to Earth as hail.

 As hail moves through the cloud it picks up a negative charge as it rubs against smaller positively charged ice crystals. A negative charge collects at the bottom of the cloud where the heavy hail collects, while the lighter ice crystals remain near the top of the cloud and create a positive charge. The negative charge is attracted to the Earth’s surface and other clouds and objects and when the attraction becomes too strong, the positive and negative charges come together, or discharge, to balance the difference in a flash of lightning. The rapid expansion and heating of air caused by lightning produces the accompanying loud clap of thunder.

 Thunder and lightning facts:

  • A bolt of lightning lasts on average for about one 10,000th of a second.
  • The average speed at which the lightning cuts through the air is 270,000 mph.
  • There are several types of lightning, the most common being “sheet lightning” in which the discharge of positive and negative charges occurs within the cloud.
  • The risk of being struck by lightning is minimal and ninety percent of lightning travels from cloud to cloud. Lightning takes the shortest and quickest route to the ground, usually via a high object standing alone.
  • The average annual frequency of lightning is less than 5 days in western coastal areas of the United Kingdom and over most of central and northern Scotland, and 15 to 20 days over the east Midlands and parts of southeast England

Get more facts from our thunderstorms fact sheet.

See lightning observations for the last three hours on our observations map.





Met Office in the Media: 04 May 2011

4 05 2011

There has been widespread coverage of the April climate statistics following what has been the warmest and 11th driest April on record. The Met Office appeared on the BBC One, Six and Ten O’Clock News as well as the News Channel, BBC Radio Four 6 O’Clock News and the ITV News.   The effects of the dry and warm weather have been felt in some areas with many news channels reporting on the heathland and moorland fires in the UK and on the impacts of the fine weather on farming.

The Met Office is working closely with the Environment Agency and water companies regarding water resources and is also working with the National Farmers Union on the current spell of dry weather, its impacts and the weather in the coming weeks.

The Met Office is also working closely with a number of Fire and Rescue services across the UK, helping them with forecasts of wind and weather to support their continued efforts of bringing the wildfires under control. Breezy weather over the last few days has hampered efforts, but winds are now gradually easing and this will help the firefighters in their efforts.

The impacts of weather have been recorded in business as well with Thornton’s reporting that the fine weather has negatively affected business, while conversely the fine spring weather has boosted sales at Next. The weather is known to impact retail business and the Met Office offers a range of services to support the retail sector manage the weather.








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