Cool, wet August ends fairly average summer

29 08 2014

After a dry and warm start, summer 2014 is set to end on a rather average note – with temperatures and rainfall close to normal levels for the season.

Using figures up to 27 August and then assuming average conditions for the final few days of the month, Met Office statistics show the UK mean temperature for this summer will be around 14.8C. This is just 0.5C above the long term average (1981-2010).

Rainfall overall is close to average, with the UK having seen 246.7mm of rain – which is just over the long-term average of 241.0mm. Rainfall from the final few days of August will add to this number, so overall the summer will be slightly wetter than average.

As ever when looking over a whole season, the statistics mask some big variations between each month.

June and July were both characterised by drier and warmer than average conditions across the UK which meant the summer was already one of the best we’ve seen in recent years.

UK rainfall as a percentage of the long-term (1981-2010) average

Map showing August UK rainfall as a percentage of the long-term (1981-2010) average for the month

August bucked that trend, however, with cooler and wetter than average weather. Taken together, this has led to the fairly average final statistics for summer.

Looking specifically at the early August figures, also released today, the UK mean temperature up to the 27th of the month is 13.8C which is 1.1C below the long-term average. This ranks it as currently the coolest August since 1993, but that could change when the final few days of the month are added.

August is also the first month since November 2013 to have been cooler than average, breaking an eight month run.

In terms of rainfall, August has been much wetter than average, with 127.1mm of rain which is 142% of the long-term average (89.5mm). This makes it the 18th wettest August in the records, but it may climb higher when the figures for the whole month are available.

 

Mean Temperature Rainfall
Summer* Actual (°C)
Diff from Avg Actual (mm)
% of Avg
UK 14.8 0.5 258.2 107
England 15.9 0.4 211.6 109
Wales 14.8 0.3 257.5 90
Scotland 13.1 0.6 338.4 111
N Ireland 14.3 0.4 244.6 96

*Please note these are projected numbers that include statistics from 1 June to 27 August, then assume average conditions for the final few days of the season. They may not accurately represent the final full-season figures.

 

Mean Temperature Sunshine hours Rainfall
August** Actual (°C)
Diff from Avg Actual (hours)
% of Avg Actual (mm)
% of Avg
UK 13.8 -1.1 154.2 95 127.1 142
England 14.9 -1.2 169.7 93 103.4 149
Wales 13.9 -1.0 152.3 91 128.2 119
Scotland 11.9 -1.1 132.4 99 169.0 145
N Ireland 13.3 -1.0 134.2 99 112.8 116

** Please note these are preliminary statistics from 1-27 August. The final figures will change once statistics from the final few days of the month are included.





A wet start to August

15 08 2014

The UK has already seen nearly its entire ‘normal’ rainfall for August in the first half of the month.

Figures up to the 13th of August show there has been 86.1mm of rain so far in the UK, just short of the 89.5mm long-term (1981-2010) average.

Looking at individual countries, Scotland has already seen more than its full-month average with 121.4mm of rain so far compared to the average of 116.7mm. The Inverness and Moray areas have been particularly wet, with significant flooding from ex-hurricane Bertha on 10 to 11 August.

Rainfall for England and Northern Ireland so far is just under the full-month average, while Wales has been the driest relatively speaking – with 83.2mm of rain making up 77% of its full-month average. Normally at this stage you would expect about 42% of the average to have fallen.

With regards to temperatures and sunshine, the month has been much closer to average so far.

The UK mean temperature is currently 15.2C, which is 0.3C above the full-month average.

UK sunshine hours are at 77.8 hours, which is 48% of the full-month average – so just ahead of where we’d expect after 13 days of the month.

While these figures are interesting, they don’t tell us where the month will end up overall – we’ll have to wait until the full-month figures are in before deciding where this August fits in to the records.

As we head in to next week there should be a good deal of drier weather but with northerly winds bringing in cooler air it will feel colder than of late, especially at night.

This will feel noticeably cool in the wind, so people heading out in the evening may want to take a few extra layers.

Mean temperature Sunshine Rainfall
1 – 13 August 2014 Actual

Diff from 81-10 average

Actual % of 81-10 average Actual % of 81-10 average
Celsius Celsius hours % mm %
UK 15.2 0.3 77.8 48 86.1 96
England 16.5 0.4 91.8 50 64.7 93
Wales 15.3 0.3 85.1 51 83.2 77
Scotland 13.2 0.2 55.3 41 121.4 104
N Ireland 14.5 0.2 61.9 46 92.7 95




October set for top ten warmest

1 11 2013

5 November 2013 Update – The full month figures are available in our latest blog

Early statistics for October up to the 28th of the month suggest this October is likely to be one of the warmest in records dating back to 1910.

Map showing relative warmth of October temperatures across the UK.

Map showing relative warmth of October temperatures across the UK.

The mean temperature for the UK from the 1st to the 28th is 11.6 °C, which is 2.1 °C above the long-term (1981-2010) average. It’s currently ranked joint fifth warmest in the records, but this could change once the final three days of data have been included.

Mild temperatures were experienced across all parts of the UK – with October currently being in the top ten warmest for England, Wales, Scotland and Northern Ireland. However, it was particularly mild in Wales, with this October currently ranked as the joint warmest on record alongside 2001.

There were no autumn heat waves through October, just a persistence of mild conditions – particularly mild nights – and frost has been rare through the month.

October 2013 is also notable because it was dull and, for most places, relatively wet. Sunshine hours are currently below the long-term average, while rainfall is already above ‘normal’ levels for everywhere apart from Scotland – which is about average.

Below are figures from 1-28 October, and we’ll update on the full-month figures early next week.

Below is a table showing statistics for 1-28 October, and we’ll update with full-month statistics early next week.

Mean temp Sunshine Rainfall
October 1-28 Actual (°C) Diff to Avg Actual (hrs) % of Avg Actual (mm) % of Avg
UK 11.6 2.1 67.3 73 147.6 116
England 12.6 2.2 74.4 72 131.6 143
Wales 12.3 2.4 66.7 72 208.9 123
Scotland 9.7 1.8 52.7 70 157.9 90
N Ireland 11.2 1.8 84.1 96 145.6 122




How powerful was Monday’s storm?

30 10 2013

The storm that swept across southern parts of the UK caused widespread disruption and included a gust of almost 100mph, but how does it compare to previous storms?

It’s not just the numbers

In terms of the severity of the winds, you don’t have to go far back to find a more powerful storm than this – in January 2012 we saw winds of over 100mph in Edinburgh for example.

There are two things that made this storm so significant. Firstly, the timing – arriving in October when the trees are in full leaf and therefore much more vulnerable to strong winds.

Secondly the track of this storm was key. Along the northern and western coasts of Scotland and northern Ireland winds of 70-80mph are not that exceptional because they are on the more usual track of Atlantic storms.

However, powerful Atlantic storms are seen much more rarely across southern parts of England and Wales – which means these areas are much more susceptible to strong winds.

All this combined meant that the storm had a significant impact – with fallen trees causing the majority of disruption.

Satellite image showing the storm tracking across the UK

Satellite image showing the storm tracking across the UK

When did we last see a storm like this?

With that in mind, to find a similar storm we’d have to look at those which affected southern parts of England at a time when leaves are still on the trees (likely to be autumn).

To find a storm of similar strength that fits these criteria you’d have to go back to 27 October 2002. That storm brought winds of similar, or higher speeds, affecting most of England and Wales, and leading to widespread impacts.

Where does Monday’s storm rank in the longer term records?

There are many different ways of comparing storms – from looking at the strongest gusts, to mean wind speeds, to the area affected or the severity of impacts.

The Met Office National Climate Information Centre (NCIC) looked at autumn storms in southern England over the past 40 years, analysing the number of weather stations across the region which recorded a gust of 60 knots (69mph) or more for each storm.

From this they put together the ranking below which suggests Monday’s storm was within the top 10 most powerful autumn storms in southern England in the past 40 years.

The storm of October 2002 comes top of this ranking – followed by the ‘Great Storm’ of 16 October 1987.

Mike Kendon, from the NCIC, said: “This is just one technique for analysing storms and doesn’t necessarily tell us how severe an impact any particular storm had. On 16 October 1987, the maximum gusts we saw were much more powerful than those seen in 2002, and it was those very powerful winds – of up to 115mph – which caused the majority of the damage.

“What our analysis does tell us is that Monday’s storm was certainly one of the most significant autumn storms for at least a decade in terms of its strength and its impacts – even if it’s not on a par with some of the most powerful or damaging storms we have seen in the UK’s historical records.”

DATE OF STORM

STATIONS WITH >69MPH GUST

27/10/2002

36

16/10/1987

28

28/10/1996

24

30/10/2000

21

11/11/1977

18

28/10/1989

18

28/10/2013

16

07/09/1974

14

24/10/1998

14

14/11/1977

13








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