More warm weather this week – but what’s in store for the summer?

13 04 2015

This week is set to see some unseasonably warm weather for parts of the UK – with temperatures expected to climb to the low to mid-20s Celsius in the south on Tuesday and Wednesday.

Warm air flowing up from the south west will combine with high pressure, bringing settled conditions and sunny spells for many.

Warmest days of the year so far

This week’s above average temperatures follow on from a similar spell last week, which saw temperatures top out at 21.9C at St James’s Park in London on Friday.

This was the ‘warmest day of the year so far’, but It looks like Tuesday and Wednesday will top that – which is to be expected as we head through spring and edge closer to the start of summer.

Unfortunately, the weather we get in April doesn’t necessarily tell us anything about the kind of summer we can expect. We’re still in the midst of spring, so it’s far too early to say what the months of June, July and August may hold.

Summer ‘heatwave’ speculation

That hasn’t stopped speculation about heatwaves, the warmest summer ever and record temperatures in the media. Some stories cite our three month outlook for contingency planners as proof of the impending heatwave, but this is in no way an accurate reflection of what it shows.

The outlook shows probabilities attached to different scenarios for temperature and rainfall over the whole three-month period it covers. This is useful for those who use probabilities to plan ahead on longer-timescales, but not very useful for deciding where and when to go on your UK summer holiday, for example.

What does the longer outlook show?

Our current three month outlook does show that above average temperatures are more likely than below average temperatures for the April-June period. The outlook is essentially the scientific equivalent of factoring the odds on a horse race and, just like a horse race, the favourite doesn’t always win.

It’s also important to note that above average temperatures over a three-month period could come about in a variety of ways in terms of actual weather – we can still see warmer than average temperatures when it’s cloudy and wet, for example. Also, even in an above average three-months not all individual months would need to be above average.

This just reinforces the point that the contingency planners outlook doesn’t tell us what specific weather we are going to see at a specific location. For the best information on the weather ahead, people should use the Met Office’s 5-day weather forecast supplemented with our 30-day outlook.

By keeping up to date with the latest forecast, you’ll always have the most up-to-date and accurate view of the weather in store for the UK.





Air Quality Forecast

17 03 2015

Localised areas of Greater London are currently recording Moderate to High levels of air pollution. More widely across Eastern parts of the UK, Moderate levels of pollution are also being recorded. Due to the current weather conditions these levels are likely to remain Moderate to High in certain areas for the next 24 hours.

Although these conditions are going to be short-lived, and while the great majority of people will not be affected by short-term peaks in air pollution, some individuals, such as those with existing heart or lung conditions, may experience increased symptoms. Those vulnerable members of the public can find further information on health advice here.

The Met Office is working very closely with Defra and Public Health England to ensure they have the most up-to-date and accurate air quality forecasts in order to provide relevant advice to the public.

Current Weather Conditions

Throughout today and into tomorrow high pressure will continue to draw in air and pollutants from the continent which adds to the pollution building up in urban areas.

High pressure is also currently sitting to the East of the UK bringing us calm and settled weather allowing pollutants to become trapped close to the ground.

How long will it last?

From tomorrow morning the high pressure will move westwards across the UK and start to bring cleaner air from the North and North East Europe, which will start to disperse pollution. By the end of Thursday pollution levels across the UK should return to Low values.





Holiday Dust

24 02 2015

At this time of year, many of us are in search of some winter sun, and a popular destination for Brits abroad is Egypt.

Typical conditions in Cairo at this time of year are fairly warm, dry and sunny. On average in February you could expect to see daytime highs of 21C, 8 hours of sunshine per day, and 1 wet day in the whole month. However, there may be some disappointed holidaymakers at the moment, as rather than sunshine; there is dust in the forecast. A dense dust plume has been developing across Libya and Egypt and will continue to grow over the coming days.

A deep area of low pressure in the central Mediterranean has given some very unsettled weather over recent days, and will continue to bring heavy rain and snow to northern parts of Algeria, Tunisia and perhaps western parts of Libya over the next few days. Very strong winds around the low will generate dust storms and sand storms and these will move across the rest of Libya and into Egypt during the first part of this week.

The dust storms will be severe and widespread enough to cause some disruption to air travel in the region, with perhaps some public health issues also.

The deep pink area in this satellite picture is the dust, and the line of dust stretches right up towards Greece.

The deep pink area in this satellite picture is the dust, and the line of dust stretches right up towards Greece.

These intense dust storms are often called Haboobs, which were first named in Saharan Sudan. They are frequently associated with thunderstorms or even small tornadoes, and usually last about three hours. The storms tend to develop late in the day during summer, and are sometime followed by rain. They can transport and deposit huge quantities of sand or dust, moving as an extremely dense wall that can be up to 100 km wide and several kilometers high.

Dust storm

For more information about the weather abroad, visit our holiday weather section.





Two cyclones to hit Australia

19 02 2015

Whilst here in the UK, we are coming towards the end of our winter season, Australia is coming towards the end of summer, but is in the middle of its cyclone season, and unusually there are currently two tropical cyclones affecting the country.

Severe Tropical Cyclone Lam is currently to the north of Australia’s Northern Territory, in the Arafura Sea. The storm is expected to make landfall on Thursday as a category 4 storm, between Milingimbi and Gapuwiyak. Huge rainfall figures are forecast, with 300 to 600mm daily, potentially adding up to more than 800mm in places throughout the storm event, with flooding likely inland, as well as coastal flooding and damaging winds. Residents close to the coast have been advised to be ready to move to shelter with emergency kit. However, as the area is not densely populated, significant impacts are not expected. The nearest large population centre is Darwin, and although it is likely that there will be some wet and windy weather here, it is not expected to be anything that Darwinians aren’t used to.

Credit: Courtesy of the Naval Research Laboratory

Credit: Courtesy of the Naval Research Laboratory

Storm track and warning areas for Tropical Cyclone Lam

Storm track and warning areas for Tropical Cyclone Lam

Meanwhile, Severe Tropical Cyclone Marcia is heading towards the Queensland coast, and is expected to make landfall between Mackay and Gladstone on Thursday night as an extremely powerful category 5 storm. The Australian Bureau of Meteorology are forecasting Marcia to track inland for a while and quickly weaken, before turning parallel with the coast, which keeps the main risk area to the north of Brisbane. However, there is some uncertainty with the exact track of the storm, and if it were to remain closer to the coast, Brisbane could be in line for a significant amount of rainfall, potentially as much as 400mm. Destructive winds are likely around the coast and abnormally high tides will be experienced with water levels expected to rise above the highest tide of the year. Dangerous storm tides are forecast as the cyclone crosses the coast, as well as treacherous surf on exposed beaches.

Credit: Courtesy of the Naval Research Laboratory

Credit: Courtesy of the Naval Research Laboratory

Storm track and warning areas for Tropical Cyclone Marcia

Storm track and warning areas for Tropical Cyclone Marcia

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.





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.





Untangling the global drivers of UK winter weather

25 11 2014

As we head towards the start of winter, which starts for meteorologists on 1 December, there’s always a great deal of media and public speculation about what weather we might have in store.

To answer that question, we need to look beyond the UK. The worlds’ weather is interconnected, and there are certain large scale global drivers which we know have influences on UK weather at this time of year – so what are these doing at the moment?

El Niño, which sees unusually warm sea surface temperatures across the tropical Pacific and can increase the risk of cold winter conditions in the UK, has been much discussed after initial signs of development earlier this year.

Its progress has been slow, however, and while there remains a good chance of a weak event by the end of the year it is also possible that El Niño conditions will remain neutral. In any case, this factor is not expected to be strong enough to exert much influence on weather patterns in Europe during the next three months.

The North Atlantic Oscillation (NAO) describes differences in the usual pressure patterns over the North Atlantic – with positive and negative phases.

A positive phase is thought more likely than a negative one on average over the next three months. This is characterised by enhancement of the westerly winds across the Atlantic which, during winter, brings above-average temperatures and rainfall to Western Europe.

As we head later into winter, confidence about the heightened likelihood of positive NAO reduces – suggesting chances of drier and colder conditions return closer to normal.

The Quasi-Biennial Oscillation (QBO) sees high level (stratospheric) winds over the equator change from westerly to easterly phases – and it’s currently in the latter of the two.

In winter months this can lead to a greater incidence of high pressure blocking patterns over the northern hemisphere, which would increase the probability of colder and drier weather across Europe. Essentially this is providing an opposite signal to the NAO.

There are other factors to consider too. For example, Arctic sea ice extent is slightly below average but as yet it is not clear whether this might have an impact on weather patterns in the UK.

No single one of these drivers will determine the UK’s winter on its own – instead they all interact together to govern the weather trends we can expect over the coming months.

Disentangling these different influences remains a challenging area of science which the Met Office is improving all the time, but detailed and highly certain UK outlooks are not possible over these timescales.

The Met Office’s long-range outlooks give probabilities based on scenarios of being considerably wetter or drier, colder or milder than usual.

Currently the outlook for December 2014 to February 2015 suggests that milder and wetter than average winter conditions are slightly more likely than other outcomes. However, compared to day-to-day weather forecasts, the probabilities are much more finely balanced – for example, the outlook gives a 1 in 4 chance of the mildest scenario and a 1 in 10 chance of the coldest scenario. These numbers suggest it would be a mistake to interpret the outlook for a very mild outcome as ‘highly likely’; likewise very cold conditions cannot be ruled out.

The outlook gives similar probabilities for precipitation (rain, hail, sleet and snow), with the chances of the wettest scenario being 1 in 4 and the chances of the driest around 1 in 10.

These three month outlooks cover a whole three month period, taking into account both day and night, as well as the whole of the UK. This means that even in the event of, say, an overall mild winter we could still see spells of cold or very cold weather.

With this in mind, what exactly we’ll see for the winter ahead remains uncertain. In terms of strong winds, heavy rainfall, cold snaps or even snow, while longer-range outlooks can give us general tendencies, the details can only be predicted by our day-to-day weather forecasts.

The Met Office’s accuracy over all timescales is world-leading, however, so you can trust that we’ll keep everyone up-to-date with all the latest information on the weather whatever the winter has in store.





Wet wet wet this winter?

17 11 2014

Every year there’s a huge amount of media speculation about what weather we’ll see during winter, and this year is no different.

After a recent slew of stories claiming we’re in for the coldest winter on record (which weren’t based on information from the Met Office), there are now stories claiming we’re forecasting the wettest winter in 30 years.

That’s not the case and appears to be a misunderstanding of our three-month outlook for contingency planners.

First of all, last winter was the wettest in our digital records dating back to 1910, so if we were to have a wetter winter than that it would be the wettest in over a century – not just for 30 years.

But that’s not what our contingency planners outlook says. As we’ve pointed out here many times in the past, this product isn’t like our short range forecasts – it doesn’t tell you definitively what the weather is going to be and that’s why it’s not really that useful for the public.

What it does do is make an assessment of the likelihood of seeing wetter or drier than average, and milder or colder than average conditions for the whole of the UK for the whole three month period.

Recent outlooks have been signalling increased risk of milder and wetter conditions for the past couple of months, and indeed that’s what we have seen through October and the start of November. So the most likely predicted outcome is what actually happened for these months – but that won’t always be the case.

While the recent three month outlooks also highlighted the risk of more unsettled than average conditions, this does not give specific details or tell us whether any records will be broken.

For detailed weather forecasts, our five-day forecasts and weather outlooks to 30-days give the best and most up-to-date advice.





Severe weather to affect western France

12 08 2014

A spell of severe weather is expected to affect parts of France overnight and through Wednesday morning as an area of low pressure makes its way in from the Bay of Biscay.

The  area of low pressure highlighted in the satellite image above is expected to deepen and develop before affecting parts of France this evening and overnight.

Pressure chart for 1 am Wednesday 13 August

Pressure chart for 1 am Wednesday 13 August

Forecast rainfall for 1 am Wednesday 13 August

Forecast rainfall for 1 am Wednesday 13 August

 

 

 

This brings the risk of severe thunderstorms across western, then southern France overnight and during Wednesday morning. This will bring the potential for flash flooding and will give squally winds, with disruption to local infrastructure and to holiday makers in the region. Very strong winds and high seas are also likely for a time overnight along the western coastline of France. Meteo France currently has severe weather warnings in force.

 

This area of wind and rain should then move quickly across Switzerland and southern Germany during Wednesday afternoon.





Rain over the Bank Holiday Weekend, with more to come

27 05 2014

The Bank Holiday weekend saw a good deal of dry and bright weather in places, but there was also heavy rainfall in some spots over the three days with some significant rainfall totals.

Much of England and Wales had a wet Saturday as rain pushed northwestwards with heavy, and thundery showers following.

Sunday brought heavy showery rain to western and northern parts of the UK, with 25 mm of rain falling in three hours around the Edinburgh area.

Heavy rain pushed in from the southeast on Bank Holiday Monday, whilst to the west and north of this there was some sunny weather, but also heavy and thundery showers for Cornwall, Northern Ireland and Scotland.

Here are the highest UK rainfall totals for each of the three days of the Bank Holiday:

 

Rainfall totals from 0900 Saturday 24 May – 0900 Sunday 25 May
Site Area Amount (mm)
Liscombe Somerset 32.2
Usk Monmouthshire 29.0
Tredegar Gwent 23.4
Okehampton Devon 22.5
Waddington Lincolnshire 22.0
Sheffield South Yorkshire 22.0

 

Rainfall totals from 0900 Sunday 25 May – 0900 Monday 26 May
Site Area Amount (mm)
Edinburgh, Gogarbank Midlothian 26.2
Cardinham Cornwall 17.8
Edinburgh, Royal Botanic Garden Midlothian 17.4
Tyndrum Perthshire 17.2
Camborne Cornwall 14.2

 

Rainfall totals from 0900 Monday 26 May – 0900 Tuesday 27 May
Site Area Amount (mm)
Wattisham Suffolk 31.2
Brooms Barn Suffolk 25.4
Cavendish Suffolk 21.8
Charsfield Suffolk 19.2
Cambridge Cambridgeshire 17.0

 

Looking ahead through the rest of this week there is more rain to come, particularly for eastern and northeastern England, while Scotland (especially the north) has the best of the warm, sunny weather.

Suffolk has already seen heavy rainfall through Tuesday morning with over 30 mm of rainfall at Wattisham through the first 9 hours of the day.

This is going to push northwards through Tuesday into Norfolk and Lincolnshire. A Met Office yellow warning has been issued to warn of rainfall amounts reaching around 30mm in some spots which could lead to some localised flooding.

There are also going to be some heavy showers over southern parts of Wales and parts of the West Country.

Wednesday will again be wet for many, especially around northeast England with parts of Yorkshire at risk of over 30 mm, for which another yellow rainfall warning has been issued. With strengthening winds this will make it feel quite unpleasant at times.

More showers or longer spells of rain are expected for Thursday, before things should turn generally drier, brighter and warmer by the weekend.





Spring has sprung

5 03 2014

Warmer, drier weather is on the way for parts of the country.  As we move through the week a north–south divide develops across the UK with Scotland, Northern Ireland, northern England and parts of Wales being changeable and windy. However in the south high pressure will dominate  bringing dry weather for the weekend, with the best of the weather in the Southeast.

Temperatures are expected to reach mid to high teens in the South this weekend (8th – 9th March), while northwest England and Scotland are likely to see spells of strong winds and rain and there is a risk of overnight frosts.

This is in sharp contrast to the record breaking winter we have just experienced.  It was the wettest winter for the UK, England, Wales and Scotland, and the second wettest winter for Northern Ireland in the record series dating from 1910. It was the stormiest UK weather for 20 years with at least 12 major winter storms affecting the UK in two spells from mid-December to early January, and again from late January to mid-February.

For a time early next week the temperatures are expected to return to nearer normal, or slightly above, the average for the time of year (9 °C).  High pressure is again expected to dominate through next week leaving largely settled conditions it should continue to feel “spring like” with some sunshine around and light winds.

When does Spring start?

Meteorologically speaking spring stretches from 1 March to the end of May. Astronomically, spring typically starts on the day of spring equinox, around the 20 March in the Northern Hemisphere.

Weather in spring is often calm and dry with temperatures rising in the day but staying cool at night.








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