What is the wettest city in the UK?

20 10 2014

We often get asked the question about where is the wettest town or city in the UK – and there are some news stories on this subject circulating in the media at the moment.

While the current stories use some of our figures, this isn’t an analysis by us and wasn’t done using our complete records from across the UK.

When it comes to answering what, on the face of it, is a relatively straightforward question – the reality is that it’s a lot more tricky than it first seems.

First of all, which measure should you use? There are rain days, which denote every day which sees more than 1mm of rain. Then there is total rainfall, which denotes the total accumulated rainfall over a period of time.

Which gives the better picture of a rainy city? There’s certainly room for debate.

Secondly, we have thousands of weather observation sites spread across the UK providing data on temperature, rainfall and other factors.

Map shows the 1981-2010 average annual UK rainfall based on individual station data - but it doesn't highlight individual towns and cities.

Map shows the 1981-2010 average annual UK rainfall based on individual station data – but can’t be used to make conclusions about individual towns and cities.

Towns and cities are generally quite large features on a map and one area could potentially have numerous weather stations.

Let’s take Huddersfield as an example. There are two rain gauges in the town that we have averages for – one on the west side sees 1028 mm a year, while another station further east sees 843 mm a year.

This demonstrates the fact that local features such as hills, or even mountains, as well as coasts and other features can all play a role in local rainfall – so there may be differences across a town or city.

It is possible to do a detailed analysis, but this would always require a clear basis for comparison.

It’s a lot more straightforward to look at individual stations. Using this data, we can see that the UK rain gauge in our archive with the highest average annual rainfall total is Crib Goch (Gwynedd) with 4635 mm of rain followed by Styhead (Cumbria) at 4562 mm.

For rain gauges located at elevations below 200 m the wettest place is Glenshiel Forest (Ross and Cromarty) at 3778 mm, but none of these are located in major towns or cities.

You can explore more about UK climate averages and statistics in our UK Climate pages.





October 2013 one of the top ten warmest

5 11 2013

Provisional Met Office statistics for October show it was one of the warmest in the national record dating back to 1910.

The mean temperature for the UK is 11.2 °C, which is 1.7 °C above the long-term (1981-2010) average. This makes it the 9th warmest on record, and means that five out of the top ten warmest Octobers have occurred since 2000 – the others being 2011 (11.3 °C), 2005 and 2006 (11.7 °C) and the warmest on record 2001 (12.2 °C).

Mild nights were a feature across the UK, with most stations south of Scotland yet to report an air frost.

Map showing October rainfall amounts relative to 1981-2010 average

Map showing October rainfall amounts relative to 1981-2010 average

October 2013 is also notable because it was, for most places, dull and relatively wet. Sunshine hours for the UK were 83 % of the long term average, while rainfall was 27 % above average. For England this was provisionally the wettest October since 2000 and equal-8th wettest in the series.

Northern Ireland and the Western Isles of Scotland have had around average sunshine, but Shetland, south-east Scotland and the north-west of both England and Wales have been particularly dull.

Mean temp Sunshine Rainfall
October 1-28 Actual (°C) Diff to Avg Actual (hrs) % of Avg Actual (mm) % of Avg
UK 11.2 1.7 77.2 83 161.1 127
England 12.2 1.9 87.3 85 139.1 152
Wales 11.9 2.0 77.6 83 223 131
Scotland 9.4 1.4 58 77 181 103
N Ireland 10.8 1.4 91.5 104 159.6 133

A full summary of the month will be available on our climate pages shortly





Is 2012 the wettest year on record?

31 12 2012

We announced last week that 2012 is already the wettest year for England in our records dating back to 1910, but we’re still waiting to hear whether it’s the wettest on record for the UK.

The latest figures we have for 2012 go from 1 January to 26 December, and show that during that time we’ve had 1291.2 mm of rain for the UK – meaning it is currently the 4th wettest year on record.

It’s 46.1 mm short of the record of 1337.3 mm, set in 2000, so if 46.2 mm of rain falls between 27-31 December we will have a new record.

It’s likely to be fairly close-run, but it’s impossible to say whether 2012 is a UK record for rainfall until all the data come in from our weather observation sites around the country.

This information should come in on the 1st and 2nd of January, then all the data will need to be processed and we expect to have a provisional answer on Thursday, 3rd January.

We’ll post the news here on our blog as soon as all the provisional statistics for 2012 come in.





UK rainfall over the last eight days

27 11 2012

After a dry start to the month, the last eight days have seen some very wet weather affect the UK, causing widespread flooding and disruption. So just how much rain has the UK seen and where has been wettest? The following maps show the full picture.

UK rainfall from 19-27 November 2012

The darkest blues on the map above show the areas that have seen the most rainfall, with South West England, Wales and parts of Northern England being particularly affected. How do these totals compare with the monthly average for November?

Eight day rainfall totals compared to whole November average

This map shows that areas from North East England through the Midlands to South West England have seen above average rainfall during the last eight days. However, parts of Northern Ireland and Scotland have seen very little.

As always, we have worked closely with the Environment Agency throughout the recent weather and have issued a series of accurate and useful forecasts and warnings which have helped emergency responders, county councils and members of the public stay informed about the latest developments.

Assistant Chief Constable of Devon and Cornwall Police, Paul Netherton, said: “I would like to formally thank and recognise the hard work of the Met Office over the past week. The information provided was invaluable and enabled the responders in Devon, Cornwall and the Isles of Scilly to prepare and respond effectively to assist our communities.”

For the rest of this week it looks as though there will be some respite from the rain with much drier conditions forecast. It will be colder though, with an increased risk of frost, fog and even ice towards as we head through the next few days.





Is it the wettest UK summer on record?

26 08 2012

This summer started with the wettest June in the UK in the national records which go back to 1910 and was followed up by a wetter than average July (16th wettest), so are we set for the wettest summer on record?

Officially, in meteorological terms, summer runs from the start of June to the end of August – so there are still a few days to go for this year.

The Met Office holds many different climate datasets but uses the UK national series that goes back to 1910 when referring to records.

In this dataset, the record to beat was set in 1912, when the UK had 384.4mm of rain – although we don’t have to look too far back to find a very wet summer, as 2007 is third in the rankings with 357.8mm. The 1971-2000 average for the UK in summer is 226.9mm.

Looking at this year, we have the figures for June and July, but for the UK as a whole we currently only have data up to 15 August – which show rainfall had been slightly below average to that point.

That means we can say with some certainty that we have seen 300.8mm of rain so far this summer (145.3mm in June, 115.9mm in July, and 39.6mm to 15 August), ranking 20th in the records.

There has been a fair amount of rain since then, so that ranking is sure to have climbed – but it’s not possible to say until all the numbers have been crunched at the end of this month.

It’s important to remember that the UK total rainfall is effectively an average of the rain that falls across the whole of England, Wales, Scotland and Northern Ireland – so looking at one station, or even one country, isn’t a reliable indicator of how much rain we’ve seen for the UK as a whole.

We can say that this summer is likely to be one of the wettest on record – some may argue that, as it’s already in the top 20% in records dating back to 1910, it already is one of the wettest on record.

We can also say that this year has continued a disappointing run of UK summers which started in 2007 – all of which have seen above average rainfall and, with the exception of 2009, below average sunshine hours.

However, we cannot say where this year will finish in the rankings or whether it will challenge the record set in 1912. For that final assessment, we’ll have to wait until after the end of August.

You can see a discussion about the causes of this year’s unsettled summer in an article posted earlier on our blog.





Met Office confirms wettest June in over a century

2 07 2012

Provisional Met Office figures for June show double the average amount of rain has fallen, making it the wettest June since records began in 1910.

This is the second record breaking month of rainfall this year, with April also topping the rankings. The period from April to June is also the wettest recorded for the UK.

It is also the second dullest June on record with just 119.2 hours of sunshine, narrowly missing out on the record of 115.4 hours set in 1987. To complete the disappointing picture, it has also been the coolest June since 1991 with a mean temperature of 12.3 deg C.

Unsettled weather has never been from the UK during the past three months, with only the latter half of May seeing a spell of prolonged fine weather.

Movements in the track of the jet stream, a narrow band of fast flowing westerly winds high in the atmosphere, have contributed to the weather we have seen.

This June has seen periods of heavy and prolonged rain, as well as short but exceptionally heavy showers.

The total UK rainfall was 145.3mm – exactly twice as much as you would normally expect compared to the 1971-2000 average. This beats the previous record of 136.2 mm set in 2007.

Looking at individual countries, it has been the wettest June on record for Wales and Northern Ireland, the second wettest in England, and the eighth wettest in Scotland.

Many areas have seen extremely high rainfall – with 83 (out of 237) observation sites marking their wettest June on record. Some of these aren’t significant as they have very short recording histories, just a year in some cases, but others have been operating much longer – Otterbourne in Hampshire been operating for 119 years.

One of the key features of the month has been that the far north west of the UK, traditionally the wettest part of the country, has been remarkably dry.

Up until quite late in the month, a few stations in this area were below their record lowest rainfall amounts – but they just missed the record books with rain falling in the last few days of the month.

Met Office provisional June figures
mean temperature sunshine duration rainfall
Actual Difference from 1971-2000 average Actual % of 1971-2000 average Actual % of 1971-2000 average
degC degC hours % mm %
UK 12.3 -0.3 119.2 70 145.3 200
England 13.4 -0.2 121 67 142.6 227
Wales 12.7 0 120.6 71 205 238
Scotland 10.4 -0.6 119.4 77 129.4 152
N Ireland 12 -0.4 97.4 64 169.2 235
England & Wales 13.3 -0.2 121 68 151.2 229
England N 12.5 -0.3 105.9 63 162.5 234
England S 13.9 -0.2 129 69 132.1 222

Current or previous wettest years on record are:

· UK: (Previous) 136.2 mm in 2007

· England: 146.0 mm in 2007

· Wales: (Previous) 183.1mm in 1998

· Scotland: 155.0 mm in 1938

· Northern Ireland: (Previous) 152.6 mm in 1912.

Average UK conditions (1971-2000):

· Mean temperature: 12.6 deg C

· Rainfall: 72.6mm

· Sunshine: 169.4 hours





Met Office figures confirm disappointing June

29 06 2012

Update: Provisional Met Office figures for the whole of June are now available at: Met Office confirms wettest June in over a century

Provisional figures from the Met Office to the 27th of June show it has been a disappointing month on all fronts – with many areas being exceptionally wet, very dull and cooler than average.

Currently it is the second wettest June on record for the UK with 130.1 mm of rainfall – just 6 mm off the 2007 total, which was the wettest June in the records which go back to 1910.

It is already the wettest June on record for Wales, with 186.3 mm of rain beating the previous record of 183.1 mm set in 1998. England and Northern Ireland are currently second wettest in the records.

Looking at the figures for the whole of Scotland, it has been a relatively unremarkable month, but there have been big contrasts. North Western areas have seen an exceptionally dry month, while southern and eastern parts have joined the rest of the UK in the wet conditions.

It should be noted that totals for this month so far do not include the heavy rainfall yesterday, and with more rain in the forecast it is likely more records will fall by the end of the month.

It may not be surprising that, with so much rain, sunshine hours have been well down across the UK. There have been 104.2 hours of sunshine so far, just 62% of the long term average (from 1971-2000).

With some sunshine in the forecast, the totals will increase, but it is likely to be one of the duller Junes on record – but it’s not possible to say where it will finish. The current dullest June on record was in 1987, with 115.8 hours of sunshine.

Temperatures have also been below average, with a mean temperature of 11.9 C (0.7 C below average) making for the coolest June since 1991 in the UK.

One of the main reasons for the wet and dull weather so far this month has been the position of the jet stream, which has been much further south than usual. This has meant that rain-bearing Atlantic low pressure systems have been over or close to the UK for the whole month.

max temp min temp mean temp sunshine duration rainfall
Actual Diff from 71-00 avg Actual Diff from 71-00 avg Actual Diff from 71-  00 avg Actual % of 71-00 avg Actual % of 71-00 avg
Regions
UK 15.5 -1.3 8.6 0.2 11.9 -0.7 104.2 62 130.1 179
Eng 16.7 -1.4 9.5 0.4 13 -0.6 99.8 56 131.8 209
Wales 15.8 1 9.4 0.8 12.5 -0.2 106.1 62 186.3 216
Scot 13.6 -1.3 6.8 0.4 10 -0.9 113.1 73 108.1 127
N Ire 15.2 -1.3 8.3 0 11.6 -0.7 91.2 60 151.3 210
Eng & Wales 16.5 -1.4 9.5 0.4 12.9 -0.6 100.7 57 139.3 211
Eng N 15.6 -1.4 8.7 0.2 12 -0.7 85 51 143.5 207
 Eng S 17.2 -1.4 10 0.5 13.5 -0.6 107.6 58 125.6 211




Is this the wettest June on record?

26 06 2012

Update: Provisional Met Office figures for the whole of June are now available at: Met Office confirms wettest June in over a century

We all know that, so far, it has been a very wet June in many parts of the UK – but just how wet has it been?

Met Office figures show that, up to the 24th of the month, the UK had seen 122.3 mm of rain –ranking as the third wettest June since records began in 1910 and well over one-and-a-half times the UK average.

So this month is currently just behind the second wettest June in 1912, which saw 124.5 mm of rain, and a little way off the wettest June in 2007, which saw 136.2 mm.

Clearly there are several more days to go and there is some rainfall in the forecast, so not possible to categorically say exactly where the month will finish in the overall records – however it is safe to say it has been a disappointingly wet month.

It’s important to note the rainfall this month hasn’t been evenly spread over the UK. Some areas have seen a great deal of rain, with 52 observation sites breaking record rainfall totals.

Not all of these records are significant as some of stations only have a very short history – for example, Usk in Monmouthshire has only been taking measurements for one year. However, at the other extreme, Otterbourne in Hampshire has been operating for 119 years.

While some areas have already seen record rainfall, others are lingering close to their all-time June minimum. Six stations are currently still below their lowest June rainfall total – but this could change by the end of the month.

What is interesting as that most of the drier stations are in the far north and west of the UK – areas which we would normally expect to see the most rainfall.

UK rainfall map

Map showing rainfall up to the 24 June 2012 compared to the1971-2000 average. Many parts of the country have seen double their normal amount, while the far north west has seen much less than usual.

 

This illustrates the story behind this month’s weather, as the rain-bearing low pressure systems moving in from the Atlantic which normally track to the north of the UK have been taking a much more southerly route, soaking parts of the south while the far north west has remained unusually dry.

One of the main reasons for this is the position of the jet stream. This is a narrow band of fast flowing westerly winds (ie blowing from west to east) high in the atmosphere.

This band moves around and changes its track, and where it sits can impact the UK’s weather. When it flows to the north of the country it can guide low pressure systems away from the UK (but they often clip the far north west of the country as they pass by).

Throughout this June the jet stream has had a much more southerly track, allowing those low pressure systems – with their wind and rain – to come straight over the UK to bring heavy rain to more southern areas while the north west remains relatively unscathed.

You can find out more about the jet stream in our YouTube video.





Why does it always rain on the UK?

9 05 2012

After the wettest April in records dating back to 1910 and an unsettled start to May, parts of the UK are set to see more heavy rain today and tomorrow.

With all the wet weather, many people have been asking what is to blame and whether something unusual is going on.

In an earlier article on this blog we looked at how the jet stream has influenced the recent spell of unsettled weather, but stressed it is not the only factor at play.

While the jet stream may be an influence, there is nothing unusual about its current position and it regularly behaves in this way.

With that in mind, it’s possible to go a step further and say there is nothing unusual about the UK’s weather over the last few weeks.

That may sound odd on the back of a record-breaking wet month, but we do expect to see records broken and they do topple fairly regularly for one area or another.

The past April fits into this expectation – it was exceptionally wet, but only slightly wetter than the previous record set just a few years ago in 2000 and there are several years close behind.

We only have to look back another month to see that March was the joint warmest on record for Scotland. Looking further back, parts of the UK have seen some of their driest months on record in the last year or so, and we saw the coldest UK December on record in 2010.

The mixture of record-breaking months in recent history illustrates what’s called natural variability – which is a way of summing up the inherent random or chaotic nature of weather. This is why our weather is different from one week, month or year to the next.

Here in the UK that variability is particularly noticeable because of our location. We sit in the mid-latitudes where cold air from the poles meets warm air from the tropics, and have the Atlantic on one side and the large landmass of continental Europe on the other.

All these factors mean our weather can be highly variable and we can see periods of unsettled, wet and windy weather at any time of year – a challenge that the Met Office has to rise to every day to provide the accurate weather forecasts that you, businesses and our government partners have come to expect.








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