One year on – A look back to last winter

17 02 2015

This weekend marked the one-year anniversary of the Valentine’s Day storm, which also marked the end of a particularly stormy three-month period. A new review article – ‘From months to minutes – exploring the value of high-resolution rainfall observation and prediction during the UK winter storms of 2013/2014’ – written by 16 Met Office co-authors reviews the accuracy of our forecasting and warning of severe weather during winter 2013-14, and assesses its performance.

The paper concludes that the “prolonged period of high impact weather experienced in the United Kingdom during the winter of 2013/14 was very well forecast by the operational tools available across space and time scales.”

Here Huw Lewis, the paper’s lead author, and Derrick Ryall, Head of the Public Weather Service, look at the extreme weather last year and the role of the Met Office in communicating severe weather through the National Severe Weather Warning Service.

Analysis chart 1200 GMT 26 January 2014

Analysis chart 1200 GMT 26 January 2014

Winter 2013/2014 in the United Kingdom was remarkable. The country was battered by at least 12 major winter storms over a three month period and was officially assessed as the stormiest period that the United Kingdom has experienced for at least 20 years.

The series of storms resulted in the wettest winter in almost 250 years (according to the England and Wales precipitation series from 1766), significantly wetter than the previous wettest winter in 1914/1915.

Snapshot of UK rain radar surface rainfall rate for 2200 GMT on 23 December 2013

Snapshot of UK rain radar surface rainfall rate for 2200 GMT on 23 December 2013

The extreme weather caused widespread flooding throughout Southern England and coastal damage – most notably in the South West and Norfolk coasts. The impact of the severe winter storms on individuals, businesses and the government were substantial, including several fatalities, widespread power cuts and damaged infrastructure.

Recent advances in forecasting, technology and the scientific developments in meteorology have been considerable. These developments and improvements in accuracy mean that a four-day weather forecast is as accurate as a one-day forecast was just thirty years ago. During the course of last winter, the Met Office was able to use these forecasts to warn of any severe weather well in advance. In the case of the St Jude’s Day storm at the end of October 2013 warnings went out to the Government and the public five days before the storm even existed.

rainfall

As the accuracy of weather forecasts has evolved, so has the communication of the potential impacts of severe weather. The National Severe Weather Warning Service enables more ‘weather decisions’ which in turn help to minimise the consequences of severe weather. The Met Office was at the heart of the government response to the storms, providing advice on weather impacts through the National Severe Weather Warning Service and Civil Contingency Advisors. The Met Office also worked very closely with both the national and regional media, who in turn played a key role in ensuring that the public were fully informed about the potential impacts of any up-coming weather.

In addition to the Public Weather Service, commercial partners and customers were also provided with detailed updates throughout the period in order for them to plan effectively for logistical issues. Together, these advanced warnings helped authorities, businesses and individuals to be better prepared to take mitigating actions.

Driving further improvements in accuracy and therefore reducing the lead time and increasing the detail of severe weather warnings is one of the Met Office’s key priorities . The ultimate aim is to improve the potential for users to plan preventative measures for severe weather events much further ahead. Underpinning all of these developments is a continuing programme of scientific research and access to enhanced supercomputing over the next few years.





White Christmas?

26 12 2014

Most people woke up yesterday to a green Christmas rather than a white one.

Snow was recorded at our observation site at Lerwick and some sleet was also recorded at Wick between 11am and 12pm, however for the rest of the UK it remained dry and clear throughout Christmas Day.

To find out what the forecast for your area is for the next five days visit our website: metoffice.gov.uk





Cyclone Quartet Straddle the Pacific Ocean

8 08 2014

In the last few days a quartet of tropical cyclones have been active across the Pacific Ocean. For a period of time all four were simultaneously of hurricane intensity (winds greater than 74 mph). This is the first time this has happened in the Pacific Ocean for 12 years. Here we take a look at each of the storms and their likely impact.

Typhoons Halong and Genevieve and Hurricanes Iselle and Julio seen on 7 August 2014 Original images courtesy of University of Wisconsin

Typhoons Halong and Genevieve and Hurricanes Iselle and Julio seen on 7 August 2014
Original images courtesy of University of Wisconsin

Typhoon Halong formed near the US island of Guam and has been active in the west Pacific for over 10 days. It is now heading north towards south-western Japan and is set to bring strong winds and heavy rain this weekend to the area only recently affected by Typhoon Neoguri.

Typhoon Genevieve originated in the east Pacific and for a long time was a weak storm, even weakening to a remnant low pressure area at one stage. However, in the central Pacific Genevieve rapidly strengthened as it traversed an area of warm waters and gained hurricane status. As it crossed the International Dateline Hurricane Genevieve became Typhoon Genevieve. There is no difference between hurricanes and typhoons except that the former is used to describe tropical cyclones east of the Dateline and the latter to the west of the Dateline. Genevieve looks set to end its life as a tropical cyclone in mid-ocean well away from land.

Hurricane Genevieve as it crossed the International dateline and became a typhoon on 7 August 2014.  Image courtesy of US Naval Research Laboratory.

Hurricane Genevieve as it crossed the International dateline and became a typhoon on 7 August 2014.
Image courtesy of US Naval Research Laboratory.

Hurricane Iselle formed in the east Pacific just over a week ago. Iselle was downgraded to a tropical storm just as it made landfall over Hawaii today, but is still bringing strong winds, surf and heavy rain. Tropical storm or hurricane strikes directly over Hawaii are very rare. The last hurricane to make landfall over Hawaii was Iniki in 1992.

Rainfall radar showing Tropical Storm Iselle approaching Hawaii 8 August 2014. Image courtesy of NOAA

Rainfall radar showing Tropical Storm Iselle approaching Hawaii 8 August 2014.
Image courtesy of NOAA

Hurricane Julio is following hard on the heels of Hurricane Iselle in the east Pacific and has become a ‘major hurricane’ with winds in excess of 115 mph.

 

Julio is also heading in the direction of Hawaii, but looks likely to track a little further north than Hurricane Iselle. However, the US state could still feel the affects of Julio as it passes by on Sunday.

Official warnings of west Pacific tropical storms are produced by the Japanese Meteorological Agency . Central Pacific warnings are issued by the Central Pacific Hurricane Center and east Pacific warnings by the US National Hurricane Center. The Met Office routinely supplies predictions of cyclone tracks from its global forecast model to regional meteorological centres worldwide, which are used along with guidance from other models in the production of forecasts and guidance.

Met Office StormTracker provides a mapped picture of tropical cyclones around the globe with access to track history and six-day forecast tracks for current tropical cyclones from the Met Office global forecast model and latest observed cloud cover and sea surface temperature. We also provide updates on current tropical storms via @metofficestorms on Twitter.





May Bank Holiday – Fine and dry for most

29 04 2014

Despite some reports, Met Office forecasters are expecting pleasant weather for many over the Bank Holiday weekend, with a good deal of dry weather, rising daytime temperatures and some spells of strong sunshine at times.

Although air of polar origin moving southwards will cause much colder nights on Thursday and Friday this week, bringing air frost to some northern parts, daytime temperatures are set to recover quickly and most parts of the UK will begin to feel pleasantly warm in the sunshine this weekend.

After a chilly start on both Saturday and Sunday, many places will see dry conditions with clear and sunny periods. The best of the sunshine will be in southern and eastern areas. Some northern and western parts may be cloudier with outbreaks of rain and drizzle. However, where conditions are brighter on Sunday and Monday temperatures should be above average making it feel pleasantly warm.

Although it is too early to be certain, indications are that many parts of the country will have a fine and warm Bank Holiday Monday.

Check our local 5-day forecast for the weather forecast in your area.





Met Office in the Media: 23 June 2013

23 06 2013

There has been further coverage in the weekend papers following a workshop held here at the Met Office HQ in Exeter on a recent run of unusual seasons in the UK.

During the workshop new, early stage research by the University of Reading suggested that long-term Atlantic currents may be playing an important role in wet summers.

These are understood to operate on cycles of a decade or more, which suggests that we may see their influence on our summers for a few more years to come. While these influence the odds of a wet summer, it doesn’t rule out the possibility of decent summers over the next few years. Professor Rowan Sutton of the University of Reading has provided a guest blog which explains the research in more detail.

The Met Office has been at the forefront of global weather and climate science for 150 years through continued investment in our scientific expertise and supercomputing technology.

We use more than 10 million weather observations a day, an advanced atmospheric model and a high-performance supercomputer to create 3,000 tailored forecasts and briefings a day. These are delivered to a huge range of customers from the Government, to businesses, the general public, armed forces and other organisations.

Weather forecasting isn’t an exact science and we know that accuracy is the main driver of peoples trust in the Met Office. Recent surveys show that 83% of people trust the Met Office, 91% of the public said they found our forecasts useful and 76% said they were accurate.

We are an island nation with island weather and we forecast as accurately as we can without bias, regardless of what weather is expected. Our forecasts are right six days out of seven and we are consistently one of the top two operational weather forecasting services in the world. We can’t change the weather, but we like to help in any other way we can.

Unbiased Met Office forecasts and warnings help us prepare for and protect ourselves in times of severe weather and help us enjoy the good weather when it is here.

The Met Office has worked with the tourism industry in recent years to provide detailed forecasts for resorts, beaches and attractions with local forecasts for up to 5,000 locations across the UK. All our forecasts provide local three-hourly detail of the weather with information on the chance of rain so that visitors can plan their day out with confidence and make the most of the great British weather come rain or shine.

We have also made these forecasts easier to access for holiday makers and attraction owners. Our website widget, which attraction owners can embed on their websites, gives visitors instant access to the latest observations, forecasts and warnings, not just for today but for the next five days.

Our award winning free weather apps for Android and iPhone also give easy access to our forecasts and warnings, 24 hours a day anywhere in the UK.

At the time of launch of these local forecasts, Mark Smith, Director of Bournemouth Tourism said: “These new forecasts from the Met Office communicate weather forecast information in clearer, more appropriate and user friendly ways that allow tourists and tourism operators to better plan activities.”





Infographic: The Great Storm of 1987

16 10 2012

The Great Storm of 1987 remains one of the most talked about weather events for a generation, it even featured in the Olympic Opening Ceremony. Twenty five years on, the storm has led to numerous improvements to the science, technology and communication of forecasting which has transformed the way the UK responds to severe weather.





Met Office website widget to support local tourism

4 10 2012

Following the wettest summer in over a century, a north Devon tourism boss has suggested the Met Office delivers ‘pessimistic forecasts’. Although we can’t change the weather we’d like to help in any other way we can.

The Met Office has worked with the tourism industry in recent years to provide detailed forecasts for resorts, beaches and attractions with local forecasts for up to 5000 locations across the UK. All our forecasts provide local three-hourly detail of the weather with information on the chance of rain so that visitors can plan their day out with confidence and make the most of the great British weather come rain or shine.

We have also made these forecasts easier to access for holiday makers and attraction owners too. Such developments include our website widget which attraction owners can embed on their websites so that visitors can get instant access to the latest forecasts, warnings and observations. With a simple click the most up-to-date and accurate weather forecast, not just for today but for the next five day.

At the time of launch of these local forecasts, Mark Smith, Director of Bournemouth Tourism said: “These forecasts from the Met Office communicate weather forecast information in clearer, more appropriate and user friendly ways that allow tourists and tourism operators to better plan activities.”

In addition visitors can get our forecasts from our popular Android and iPhone Apps, mobile phones which allow you to get the latest weather forecast on the go, as well as on TV or on the radio.

The Met Office is trusted by the public to give the best possible guidance on the weather and we report the weather exactly as it is, so by putting our weather forecasts on tourist attraction websites, visitors can access the best weather forecasts available.





Using probabilities in weather forecasting

4 10 2012

Predicting how the weather will behave over the coming hours, days, weeks and months is a complex undertaking. Each timescale presents its own challenges. In an ideal world, everyone would like us to tell them exactly what the weather will do so they can make definite decisions in their local area.

Nature, however, doesn’t work like that. But one thing we can do is tell people about the probabilities of things happening.

In the short range, it is possible to predict with a high degree of accuracy what the weather has in store. However, the science does not exist to allow precise prediction of local details five days ahead. When severe weather may be on the way, it may be very unpredictable even in the short term. In these situations, uncertainty, or risk, becomes increasingly important in weather forecasting.

To forecast the weather we first gather observations from around the world to measure what the atmosphere is doing. We use these observations to set up a computer simulation of the atmosphere that represents what is happening right now. The model then calculates how the atmosphere will evolve over the coming days. Unfortunately, due to chaos, small unknowns in our observed atmosphere can grow rapidly to give large uncertainties in the forecast.

Over the last 15 years, the Met Office has developed sophisticated techniques to understand these uncertainties, called ensemble forecasts. This means we run our simulations many times instead of just once, from very slightly different starting conditions. The range of different outcomes gives us a measure of how confident or uncertain we should be in the overall forecast. On some occasions the uncertainty is quite small and we can be confident – other times much less so. This can help decision makers manage the risks associated with the weather.

Using ensembles is good science and it lets us give an indication of our certainty in a forecast. But it also presents us with a problem. How do we effectively communicate the forecast, both the bits we can be confident about and the areas where we are less confident? How can we communicate probabilities?

The Met Office is already beginning to provide more probability based information on its website. This includes information on the chance of rain and the possible range of maximum and minimum temperatures for our 5000 or so location forecasts available online. Furthermore we are using probability information within our National Severe Weather warnings and are at times supporting these with additional images and videos to explain possible severe weather.

Ken Mylne, Probability Weather Forecasting expert at the Met Office, will be presenting at the Royal Society conference ‘Handling uncertainty in weather and climate prediction, with application to health,  agronomy, hydrology, energy and economics’ taking place today and tomorrow.





A challenging forecast for the weekend

20 09 2012

This weekend’s weather forecast is proving more challenging than usual as we see signs of much more unsettled conditions developing for all parts of the UK over the next few days.

Much of the UK is set to have a fine and dry weekend with sunny spells, light winds and temperatures in the mid to high teens Celsius after some cold nights.

There is now increasing confidence that southern parts of the UK (roughly south of a line from south Wales to Ipswich) will see wet and windy weather on Sunday.

This wet and windy weather is not the remnants of tropical storm Nadine – this stays close to the Azores. However, we are expecting a new area of low pressure to develop to the west of Iberia on Saturday which will move northeast, pulling some warm air from Nadine with it. It is this that would bring wet and windy weather to the far south of England and Wales for Sunday and other parts of the UK next week.

The challenge for forecasters is to pinpoint how this low pressure area will move. The weather forecast models available to Met Office forecasters are giving slightly different answers to this problem. As Anthony Astbury, Met Office Deputy Chief Forecaster, explains: “One model brings the low over Brittany giving rain and gales in the south of England, while another brings the low further west, with the risk of wet and windy weather for southwestern England and south Wales.”

There is still uncertainty about how the low pressure area will develop and move on Monday, and therefore which areas of the UK will see the worst of the weather early next week.

However, this heralds a spell of very unsettled weather for the whole of the UK for next week, with all parts seeing unsettled and windy conditions with showers or longer spells of rain.

Keep up to date with the forecast and warnings for the latest information.





Ground-breaking forecasting keeps Olympic rowing on course

28 07 2012

Ground-breaking high resolution weather forecasting lies at the heart of the Met Office’s services to the Olympic Games, providing the best advice available to both the organisers and competitors at venues in London and across the UK.

The London 2012 Olympic Games got underway in spectacular style on Friday night. As forecast, the Olympic Park saw a brief shower in the run up to the opening ceremony but the main event stayed dry.

The Met Office has been working with LOCOG, providing both longer term planning information and up to the minute details on the likely weather conditions as the focus now moves to the sporting events.

With the rowing events set to get underway on Saturday, accurate forecasts of wind conditions will be crucial to success. Predicting the subtle shifts in wind direction and speed over a small area like the Eton Dorney rowing lake is becoming possible thanks to the introduction of some new advances.

The Met Office weather forecasting model typically forecasts the weather using grid boxes of 4 x 4 km. But the new UKV model uses a much finer scale at 1.5 x 1.5 km over the whole of the country.

Just as increasing the number of pixels on a digital camera improves the picture, reducing the size of these grid boxes can add much more detail and clarity to the forecast.

For the Olympics, the Met Office is set to take high-resolution forecasting a step further by running multiple forecasts at the same time, a technique called ensemble forecasting.

Brian Golding, Deputy Director of Weather Science at the Met Office, explained: “By running multiple forecasts with slightly different starting conditions we can get a handle on how likely a forecast is. This means we can assess the chances of weather impacts in a certain area at a certain time, so we can give much more useful guidance.”

Using this system, detailed probability forecasts of head, tail and crosswinds will be used by the rowing teams at Eton Dorney as they look for that decisive edge that may bring that prized Olympic medal.

The high-resolution ensembles will be used throughout the Olympics. They will then be subject to further research, with a view that the facility could be introduced operationally in the future. This will potentially leave a legacy that will benefit the UK well after the Olympic and Paralympic Games are over.

You can keep up to date with our weather forecasts on our website or with our specific London 2012 Olympic Games forecasts.








Follow

Get every new post delivered to your Inbox.

Join 6,624 other followers

%d bloggers like this: