Met Office continues to drive forward research on long-range forecasting

29 03 2013

The BBC Radio 4 ‘Today’ Programme have run a story this morning regarding the advice the Met Office gave to our government customers ahead of the exceptionally wet weather of April to June 2012.

This was an extreme period of weather that saw a marked change from dry conditions to very wet conditions in a very short period of time.

Following the exceptionally wet weather of late spring 2012 the Met Office provided a full report into the possible reasons for the switch from dry to wet conditions. Our report states that the advice provided in the long-range outlook for April to June 2012 issued in March 2012 ‘was not helpful’ to our government customers.

However, looking at the skill of these outlooks over many individual forecasts clearly shows that they provide useful advice to their specialist users on over 65% of occasions. In addition these outlooks are never used in isolation but form one part of a range of forecasts from the Met Office including regular monthly outlooks and highly accurate 1 to 5 day forecasts and warnings.

Facing up to the challenge of long-range forecasting

The science of long-range forecasting is at the cutting edge of meteorology and the Met Office is leading the way in this research area. We are continuing to work hard to develop the science of long-range forecasting. We are confident that long-range outlooks will improve progressively and that the successes we have achieved in other parts of the world already will, in the future be mirrored in the UK.

The Met Office constantly reviews the accuracy of our forecasts across all time scales and is recognised by the World Meteorological Organization as one of the top two national weather forecasting services in the world. We also routinely verify our short-range forecasts on our website.

The ‘big switch’ of April 2012

During March 2012 the La Nina event that had persisted from 2009 was finally waning in the Pacific (as predicted by the seasonal forecast system), although many parts of the global oceans and tropical weather patterns still retained characteristics associated with La Nina. In the northern hemisphere the jet stream was very disturbed, resulting in a wave pattern of high and low pressure regions. The UK was positioned under a strong high pressure region resulting in very dry and warm conditions. In April, the wave pattern underwent a significant shift to bring the UK under the influence of strong low pressure, with prevailing south-westerly flow and heavy rainfall.

As detailed on ‘Today’, one of the potential causes of this shift in the northern hemisphere circulation may have been associated with a shift in tropical weather patterns. In particular, this may have been caused by a strong Madden Julian Oscillation (MJO) which occurred in March. This is a large-scale tropical phenomenon which leads to disturbed weather patterns over a timescales of typically 30-60 days. This changes originating over the Indian Ocean may have influenced our northern hemisphere weather regimes. Understanding the initiation of an MJO event is, however, largely unpredictable, and remains one of the great unsolved challenges of tropical meteorology.

Due to the fact that the initiation of an MJO is largely unpredictable – combined with knowledge that often subtle, and sometimes small, shifts in hemispheric circulation patterns can make all the difference between fine, dry weather and unsettled, wet weather over the UK – it is very unlikely that its impacts could have been anticipated in any forecasts for the coming months issued in early and mid-March.

A complicated world

Finally, although one reason for the switch in the fortunes of our weather in 2012 may have been the MJO, there are other parts of the climate system which we increasingly recognise as having an influence on our weather patterns. These include the North Atlantic Ocean temperatures, solar variability, the circulation of the upper atmosphere – the stratosphere – and of increasing interest, the changing state of the Arctic.

Better understanding and representing the drivers of predictability in the global climate system that influence our weather patterns is as ever a priority for Met Office research in order to deliver improved advice and services on all timescales.





Met Office figures show we are on course for coldest March in over 50 years

28 03 2013

This March is set to be the coldest since 1962 in the UK in the national record dating back to 1910, according to provisional Met Office statistics.

From 1 to 26 March the UK mean temperature was 2.5 °C, which is three degrees below the long term average. This also makes it joint 4th coldest on record in the UK.

The table below gives details of statistics up to the 26 March for broken down by the counties used to compile climate statistics.

  mean temperature precipitation
  Actual  (deg C) Difference from 1981-2010 average (deg C) Actual (mm) Percentage of 1981-2010 average (%)
Regions        
UK 2.5 -3.0 62.2 65
England 2.9 -3.3 63.4 99
Wales 2.8 -3.0 86.2 74
Scotland 1.6 -2.5 50.3 36
N Ireland 3.0 -2.9 78.9 83
England & Wales 2.9 -3.3 66.6 94
England N 2.0 -3.5 54.0 72
England S 3.4 -3.2 68.4 118
Historic Counties        
Aberdeenshire 0.6 -3.1 67.9 86
Anglesey 3.9 -2.9 79.8 100
Antrim 2.9 -2.8 68.9 75
Argyllshire 2.5 -2.1 47.2 22
Armagh 3.1 -3.1 96.8 125
Ayrshire 2.0 -2.9 53.8 41
Banffshire 0.8 -3.1 56.4 76
Bedfordshire 3.0 -3.5 50.1 119
Berkshire 3.4 -3.2 78.5 157
Berwickshire 1.6 -3.2 65.0 108
Brecknockshire 1.9 -3.1 100.5 74
Buckinghamshire 3.1 -3.4 66.6 137
Buteshire 2.7 -2.3 58.0 36
Caithness 2.3 -1.9 45.5 52
Cambridgeshire 3.2 -3.5 40.0 102
Cardiganshire 2.8 -2.8 62.5 54
Carmarthenshire 3.4 -2.7 87.0 69
Carnarvonshire 2.8 -3.0 96.1 64
Cheshire 2.9 -3.5 42.1 72
Clackmannanshire 1.7 -2.7 65.3 57
Cornwall 5.1 -2.3 102.0 109
Cumberland 1.6 -3.3 42.1 37
Denbighshire 2.1 -3.4 66.2 75
Derbyshire 1.9 -3.7 58.8 81
Devon 4.0 -2.7 112.9 118
Dorset 4.0 -2.7 96.8 132
Down 3.2 -3.0 158.4 193
Dumfriesshire 1.3 -3.1 65.6 53
Dunbartonshire 2.1 -2.7 49.4 25
Durham 1.6 -3.4 61.9 99
East Lothianshire 1.9 -3.2 55.4 100
Essex 3.5 -3.3 44.2 110
Fermanagh 3.0 -3.0 45.6 42
Fifeshire 2.3 -3.0 58.8 89
Flintshire 2.9 -3.5 60.9 105
Forfarshire 0.9 -3.0 73.1 89
Glamorganshire 3.6 -2.8 123.1 98
Gloucestershire 3.2 -3.3 77.1 129
Hampshire 3.9 -2.9 85.4 133
Herefordshire 2.9 -3.5 80.3 134
Hertfordshire 3.2 -3.4 50.3 109
Huntingdonshire 3.1 -3.6 56.4 143
Inverness 1.3 -2.1 36.9 19
Kent 3.8 -3.1 58.2 121
Kincardineshire 1.5 -3.1 56.5 82
Kinross 1.5 -3.0 65.6 65
Kirkcudbrightshire 1.7 -3.0 79.2 54
Lanarkshire 1.2 -3.0 51.8 47
Lancashire 2.6 -3.3 41.1 45
Leicestershire 2.4 -3.8 52.4 114
Lincolnshire 2.7 -3.6 49.0 113
Londonderry 3.0 -2.8 59.3 60
Merionethshire 1.8 -3.1 98.6 62
Mid Lothianshire 1.7 -3.1 59.4 83
Middlesex 4.2 -3.3 57.7 128
Monmouthshire 3.1 -3.2 94.8 100
Montgomeryshire 2.0 -3.4 64.5 56
Moray 1.7 -2.8 39.5 60
Nairnshire 1.5 -2.9 32.0 47
Norfolk 3.0 -3.4 60.5 128
Northamptonshire 2.6 -3.6 61.0 133
Northumberland 1.5 -3.3 63.0 92
Nottinghamshire 2.6 -3.8 49.0 113
Oxfordshire 3.0 -3.3 74.3 149
Peeblesshire 0.4 -3.4 69.6 68
Pembrokeshire 4.0 -2.6 76.9 77
Perthshire 0.6 -2.6 58.8 39
Radnorshire 1.7 -3.2 87.8 91
Renfrewshire 2.5 -2.8 42.8 29
Ross and Cromarty 2.1 -2.0 35.1 20
Roxburghshire 1.0 -3.4 62.8 73
Rutland 2.4 -3.7 58.0 123
Selkirkshire 0.5 -3.1 76.5 68
Shropshire 2.6 -3.5 61.6 108
Somerset 3.8 -3.0 65.3 91
Staffordshire 2.3 -3.7 51.0 87
Stirlingshire 1.9 -2.9 53.2 36
Suffolk 3.2 -3.3 46.4 104
Surrey 3.7 -3.1 72.1 135
Sussex 4.0 -2.8 64.6 103
Sutherland 1.5 -2.4 38.8 27
Tyrone 2.8 -2.8 60.1 57
Warwickshire 2.8 -3.6 52.2 110
West Lothianshire 1.9 -3.1 49.3 62
West Suffolk 3.3 -3.5 31.8 80
Westmorland 1.2 -3.1 56.1 40
Wigtownshire 2.7 -2.8 55.5 51
Wiltshire 3.3 -3.0 76.1 118
Worcestershire 3.1 -3.5 63.9 133
Yorkshire 1.9 -3.6 59.0 84

Clearly March has been extremely cold and snowy and joins 2006, 2001, 1995, 1987, 1979, 1970 and 1962 as years when March saw some significant snowfall.

The cold weather is expected to continue through the Easter weekend and into April. You can stay up-to-date with forecasts and warnings online, through our mobile apps, facebook and twitter, and through TV and radio broadcasts.

The table below lists the coldest March average temperatures on record and details where March 2013 ranks in terms of cold months of March.

Area Coldest March

on Record

(deg C and year)

Rank of March 2013
Aberdeenshire -1.4 1947 5
Anglesey 3.6 1962 2
Antrim 2.2 1947 5
Argyllshire 1.5 1947 5
Armagh 2.9 1919/1947 4
Ayrshire 1.0 1947 5
Banffshire -1.0 1947 5
Bedfordshire 2.3 1962 2
Berkshire 2.6 1962 2
Berwickshire 0.3 1947 5
Brecknockshire 1.1 1962 2
Buckinghamshire 2.3 1962 2
Buteshire 1.5 1947 5
Caithness 0.0 1947 5
Cambridgeshire 2.6 1962 2
Cardiganshire 2.0 1962 3
Carmarthenshire 2.5 1962 3
Carnarvonshire 2.3 1962 3
Cheshire 2.6 1962 2
Clackmannanshire 0.1 1947 4
Cornwall 3.9 1962 2
Cumberland 1.0 1947 4
Denbighshire 1.4 1962 2
Derbyshire 1.5 1962 2
Devon 3.1 1962 2
Dorset 3.1 1962 2
Down 3.0 1937/1947 4
Dumfriesshire 0.5 1947 5
Dunbartonshire 0.3 1947 5
Durham 0.9 1947 4
East Lothianshire 0.2 1947 5
Essex 2.8 1962 2
Fermanagh 2.8 1947 3
Fifeshire 0.7 1947 5
Flintshire 2.4 1962 2
Forfarshire -0.6 1947 4
Glamorganshire 2.9 1962 3
Gloucestershire 2.6 1962 2
Hampshire 3.0 1962 2
Herefordshire 2.4 1962 2
Hertfordshire 2.4 1962 2
Huntingdonshire 2.6 1962 2
Inverness 0.0 1947 5
Kent 2.9 1962 2
Kincardineshire 0.3 1947 2
Kinross -0.1 1947 5
Kirkcudbrightshire 0.9 1947 3
Lanarkshire 0.0 1947 5
Lancashire 2.3 1962 2
Leicestershire 2.0 1962 2
Lincolnshire 2.4 1962 2
Londonderry 2.2 1947 5
Merionethshire 1.2 1962 3
Mid Lothianshire 0.1 1947 5
Middlesex 3.4 1962 2
Monmouthshire 2.5 1962 2
Montgomeryshire 1.3 1962 3
Moray -0.2 1947 5
Nairnshire 0.0 1947 5
Norfolk 2.5 1962 2
Northamptonshire 2.1 1962 2
Northumberland 0.4 1947 4
Nottinghamshire 2.4 1962 2
Oxfordshire 2.4 1962 2
Peeblesshire -1.2 1947 5
Pembrokeshire 3.2 1962 3
Perthshire -1.2 1947 5
Radnorshire 1.1 1962 2
Renfrewshire 0.8 1947 5
Ross and Cromarty 0.8 1947 5
Roxburghshire -0.4 1947 5
Rutland 1.9 1962 2
Selkirkshire -0.8 1947 5
Shropshire 2.1 1962 2
Somerset 3.0 1962 2
Staffordshire 1.9 1962 2
Stirlingshire 0.1 1947 5
Suffolk 2.5 1962 2
Surrey 2.8 1962 2
Sussex 2.9 1962 2
Sutherland 0.1 1947 5
Tyrone 2.3 1947 5
Warwickshire 2.3 1962 2
West Lothianshire 0.3 1947 5
West Suffolk 2.5 1962 2
Westmorland 0.4 1947 3
Wigtownshire 1.7 1947 3
Wiltshire 2.5 1962 2
Worcestershire 2.7 1962 2
Yorkshire 1.4 1947 3

The full month figures for March 2013 will be available later next week and a summary of the month will be issued soon after.





Cold Weather Alert Service extended to help support

27 03 2013

With cold weather forecast across the UK as we head through the Easter weekend and into the start of April, the Cold Weather Alert Service, which usually finishes at the end of March, has been extended for an additional two weeks.

winter-fogThe Cold Weather Plan, which has run successfully since 2011, has been developed by the Department of Health, Met Office and Health Protection Agency, and supported by AgeUK.

The purpose of the Cold Weather Plan is to help raise awareness of the dangers of cold weather on health with both the general public and professionals alike. It spells out what preparations both individuals and organisations could make to reduce health risks and includes specific measures to protect at-risk groups.

The Cold Weather Plan has been supported again this winter by the Met Office Cold Weather Alert Service, which notifies frontline staff across the health, social care, community and voluntary sectors, and AgeUK, as well as the general public across England, when cold weather could impact on our health.

The continued period of cold weather has brought substantial media focus. By extending the service we are ensuring that accurate and reliable forecasts and alerts are sent to frontline staff and carers in our health services. This will help them to look after those who are more vulnerable and ensure that they stay well and healthy during this prolonged spell of cold weather.

You can keep up to date with the latest forecasts from the Met Office on our website.





Is there a UK ‘heatwave’ on the way?

25 03 2013

There have been some headlines today suggesting the Met Office has forecast a ‘heatwave’ by the end of spring.

The articles reference a line from our March to May three-month outlook for contingency planners which refers to how our Spring weather can change depending on where large areas of ‘blocking’ high pressure systems lie in relation to the UK – something we recently wrote about when contrasting the weather this March to that of last year.

This is not, however, a forecast of what the weather is expected to be like at the end of the spring or whether a ‘heatwave’ is likely or not, but is an indication of how average temperatures may differ from normal throughout the whole three month period of March, April and May.

Clearly this is the time of year when temperatures rise in response to the sun getting higher in the northern hemisphere sky, the days get longer and continental Europe warms up. So we will undoubtedly get some warmer spells of weather as the months go on and these will be picked up in our accurate five-day forecasts, as well as our forecasts out to 30 days ahead, which gives a more general view of the weather ahead over a longer-timescale. It is our accurate five-day forecasts and weather warnings provide the best possible advice and detail on what weather to expect in the UK.

This week is set to remain very cold with further wintry flurries in places.





Latest snow depths and wind speeds – 24 March

24 03 2013

As forecast, we have seen some very wintry weather over the last few days. Here are some figures showing where the most snow has fallen.

Wittering in Cambridgeshire saw the deepest snow, with 24 cm recorded at 9 am this morning.

Many areas also saw strong winds, with a gust of 61 mph recorded at Shap, Cumbria and 48 mph recorded at Machrihanish, Argyll . These winds have caused even deeper drifts of snow in some areas.

Snow depths at 9 am 24 March

TIME SITE NAME AREA ELEVATION (m) SNOW DEPTH (cm)
09:00 WITTERING CAMBRIDGESHIRE 73 24
09:00 WATTISHAM SUFFOLK 89 20
09:00 NOTTINGHAM, WATNALL NOTTINGHAMSHIRE 117 19
09:00 SHAWBURY SHROPSHIRE 72 14
09:00 ANDREWSFIELD ESSEX 87 12
09:00 CRANWELL LINCOLNSHIRE 63 10
09:00 LEEK, THORNCLIFFE STAFFORDSHIRE 298 7
09:00 ABOYNE ABERDEENSHIRE 140 7
09:00 HIGH WYCOMBE BUCKINGHAMSHIRE 204 7
09:00 SENNYBRIDGE POWYS 307 7
09:00 SHAP CUMBRIA 252 7
09:00 COLESHILL WARWICKSHIRE 96 6
09:00 HAWARDEN AIRPORT CLYWD 11 6




Five things you might not know about thunderstorms

20 03 2013

1. Lighting can strike twice. The empire state building in New York has been struck by lightning as many as 48 times in one day.
2. The average flash of lightning would light a 100 watt light bulb for three months.
3. Lightning can strike in volcanic ash clouds. Not much is known about volcanic lightning, but we’re using it to help track ash clouds.

Volcanic lightning

Volcanic lightning

4. Thunderstorms can trigger asthma. The Met Office has worked with the NHS and Asthma UK to try and understand why.
5. The most thundery part of the earth is the island of Java where the annual frequency of thunderstorms is about 220 days per year.





February weather pictures and video summary

19 03 2013

February was rather unsettled during the first half, but much more settled for the second half as high pressure brought mainly dry but often cloudy conditions with lower temperatures. This was the longest spell of dry weather of the whole winter.

In our video forecaster Charlie talks through the weather we saw and the highs and lows of the month, weather wise.

Thank you for sharing your weather photos with us on Twitter, here’s a selection of our favourites.

You can read a full summary of the weather in February in the UK on our website.





March – a month of weather contrasts

18 03 2013

Winter seems to have hung on for quite some time this year with low temperatures, frost, ice and snow affecting many areas into late March. This isn’t altogether unusual as we are more likely to see snow at Easter than at Christmas. However, March 2012 was very different with plenty of sunshine and temperatures into the low 20s Celsius. How come?

Well, this time last year the UK was under the influence of high pressure. This gave us clear skies, plenty of sunshine and with a light southerly breeze, temperatures that were well above average. In fact, Scotland set an all time record maximum temperature with 22.8 °C at Fyvie Castle in Aberdeenshire.

Visible satellite image from March 2012

Visible satellite image from March 2012

This year, with a strong easterly wind bringing cold air from Scandinavia and Eastern Europe, we have quite the opposite with eastern parts of the UK in particular seeing snow, ice and temperatures around 20 degrees Celsius lower.

Visibile satellite image from March 2013

Visibile satellite image from March 2013

The direction of the wind therefore plays a major part in what type of weather you and I will see, especially as we have the Atlantic Ocean to our west and continental Europe to our south and east. Different wind directions bring air with different temperature and moisture contents. Meteorologically, they are termed air masses and in March 2012 we saw a Tropical Continental air mass bringing dry and warm air from the Mediterranean. This year we have been affected by a Polar Continental air mass, bringing cold air from the east. The following video explains exactly what we mean by air masses.

With different air masses constantly affecting the UK, the weather is a particularly challenging thing to forecast, especially so in March. This is because in early spring the sun is starting to rise higher in the sky and the amount of daylight hours start to increase. This means we get more heat building up in the lower part of our atmosphere. The result is slightly more energy, which in turn can lead to heavier showers. We can also see more unstable air and more active fronts as a result of greater heating. With more moisture available in the atmosphere, we also tend to see heavier or more prolonged rainfall and if this mixes with cold air, more snowfall. It makes forecasting more complicated because the extra heat and moisture adds another aspect to the weather, which tends amplify the effects of different air masses.

You can find out more about forecasting snow on our website or on the following video:





Guest blog: Met Office launches volcanic ash forecasting game for National Science and Engineering Week

15 03 2013

Today’s guest post is from our education channel for children, here’s Billy Blizzard to tell us about EVACuate…

billyblizzard

Billy Blizzard

National Science & Engineering Week (NSEW) 2013 starts today and is now a mainstay in the UK events calendar. Initiatives like this have led the cultural shift  towards science being ‘cool’, and people are now ‘getting their geek on’ in droves.

NSEW has been going for nearly 20 years now and it’s an excellent excuse for us all to take part in something scientific that relates to our daily lives. At the Met Office, science is our daily lives, so we’re very supportive of this initiative and will be celebrating the week with the rest of the UK.

In fact, to show the strength of our support we’ve created a new game ‘eVACuate!’ for people to play at home or in classrooms across the country. Based on our volcanic ash forecasting responsibilities, teams are tasked with advising the Centre for Emergency Situations with the evacuation efforts on the fictional Green Island, where FitzRoy’s Peak has started to erupt!

As the UK’s national weather and climate service, we take every opportunity to help people understand what we do and how we do it. Having a game based on mapping volcanic ash clouds highlights the vital role we play in providing weather information – and more –  for the country.

To get involved visit NSEW or play the game.

Related articles





This week’s snowfall captured by rainfall radar

13 03 2013

The rainfall radar network is a great way of looking back at how weather systems affect the UK.

Here we see rainfall radar imagery from 00:00 GMT on Sunday 10 March to 09:00 GMT on Tuesday 12 March. It shows snow showers affecting much of the UK while an area of heavier snowfall affects northern France, the Channel Islands and the far south-east of England.

radar_animation

What’s particularly interesting is that it shows really well how the showers and the heavier snowfall across the south were moving in totally different directions. The snow showers can be seen moving in from the North Sea on north-easterly winds. Meanwhile, the heavier and more persistent snowfall was moving in from the south-west as an area of low pressure tracked across France. You can see how these two systems collided over Sussex and Kent, resulting in the heavy snowfall here.

At the very end of the sequence the wind changes direction again over the north of the UK, with the snow showers being blown across Scotland from the north.

You can see current observations from our rainfall radar on our website.








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