Dual Warnings

12 11 2014

Today for the first time we have issued a new dual National Severe Weather Warning for wind and rain.

What is a Dual Warning?

A dual warning is one warning, covering one geographical area, over one period of time in the way a single warning does – but it combines two different types of severe weather. They would only be combined if they were both at the same warning level.

Any of the five types of weather warnings, Wind, Rain, Snow, Ice and Fog, can form a dual warning in any combination. So in theory Wind and Snow could be a dual warning. In practice there are certain weather types that are more likely to form a dual warning; the most likely is Wind and Rain, which is what we see today.  More information on our dual warnings can be found at the bottom of our Weather Warning page.

These new dual warnings have been developed following extensive two-way conversations with emergency responders and feedback we have recieved from the public over the past twelve months.

Until now, we would have issued multiple severe weather warnings to cover the range of warnings in place. Quite often however, situations arise where multiple impacts occur and these can now be shown on one map. This should make the information we issue easier to access.

Today’s Warning

Dual wind and rain warning

Dual wind and rain warning

The warning for wind and rain issued today covers Southwest England, Western Scotland and the Irish Sea between 07.00 and 23.45 on Thursday 13 November. A small area of low pressure will move quickly northwards throughout the day bringing a short-lived period of gales and severe gales and spells of heavy rain.

We encourage everyone to keep up to date with the latest forecasts and national severe weather warnings and to stay weather aware this winter by following the Met Office on Twitter, Facebook, Google+ and YouTube for the latest weather information. You can also sign up for severe weather alerts from us through the Twitter Alerts programme, providing critical information directly to your phone. Find out more about how to sign up for Met Office Twitter alerts.





How will activity in the Atlantic affect UK weather?

15 10 2014

There’s lots of activity going on in the Atlantic at the moment – but how will it affect the UK?

Currently there is a big area of low pressure covering a large part of the Atlantic between North America and the UK.

While it is fairly large in its size, it’s not particularly intense, powerful or unusual.

Forecast chart for 1pm on Wednesday 15 October 2014, showing large area of low pressure in the Atlantic.

Forecast chart for 1pm BST on Wednesday 15 October 2014, showing a large area of low pressure in the Atlantic.

This means that – while it may look impressive on the charts – it’s not going to bring anything out of the ordinary for the UK over the next few days.

It will, however, be generally unsettled across many parts through Friday and the weekend, as the low pressure drives a weather system across the UK.

This will bring strong winds, with gusts of up to 50mph in the most exposed parts of the west, and rain in places. However, some parts will enjoy periods of drier and brighter weather.

Tied up in the general Atlantic circulation is an area of warm air which was originally part of tropical storm Fay.

This will bring very mild air across parts of the country, with daytime temperatures possibly reaching around 20C across southeastern areas by Saturday, well above the October average for the region of 15C.

While it will be very mild, it may not feel particularly warm given the windy and often wet conditions. The unsettled weather is expected to be fairly standard for the middle part of October.

Forecast track of Gonzalo from the US National Hurricane Center.

Over the other side of the Atlantic near Bermuda, Hurricane Gonzalo is currently expected to track north and then east across the ocean over the coming days.

There is large uncertainty about the potential track of this storm, with some models suggesting that the remnants could move across the UK whilst others show them staying away from our shores.

If the ex-tropical storm does move across the country, some parts could see gales and heavy rain, but currently extreme conditions look unlikely.

As ever, we’ll keep a close eye on developments over the next few days and keep everyone up to date if it looks like there is any sign of severe weather heading for the UK.





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.





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.





Ex Bertha more likely to miss UK

6 08 2014

7 August update: The latest update about the whether ex-Bertha will affect the UK can be found in our news release

 

Tropical Storm Bertha is currently off the north east coast of the US and is likely to become an ‘extra tropical storm’ on Thursday.

It’s then expected to track across the Atlantic – and while there are still a number of possible outcomes, it looks increasingly likely that the UK will miss any serious impacts from ‘ex Bertha’.

The Met Office has been assessing the likelihood of the UK seeing any effects from Bertha by using our own forecast model alongside models from other world-leading forecast centres.

Map shows likely storm track for ex Bertha by midday Sunday.

Map shows likely storm track for ex Bertha by midday Sunday.

At the moment the majority of forecasts from those models suggest ex Bertha will track to the south of the UK as a relatively weak low pressure system.

In fact it’s debatable whether this is even ex Bertha, as the storm declines to such an extent as it comes across the Atlantic that it fragments.

Some of the warm air which it drags across then leads to a new weak low which generates an area of heavy rain. This could move across northern France and possibly clip eastern parts of the UK on Sunday.

A much smaller number of model outcomes suggest ex Bertha will move across the UK as a more distinct feature which could bring some strong winds and heavy rain. Because these outcomes are in a minority, however, they are less likely.

While there remains a good deal of uncertainty about the weather on Sunday, it currently looks as if it will be fairly unsettled with some rain and breezy conditions – but nothing too unusual for the time of year.

It’s worth noting that it’s likely that the south east of England will see some heavy rain on Friday, which is not part of Bertha. You can see more about this on the Met Office’s severe weather warnings page.

We’ll be keeping an eye on the latest outlook for the weather over the next few days and the progress of ex Bertha to keep everyone up to date with the latest information.





Is Tropical Storm Bertha heading for the UK?

4 08 2014

Update: The latest update about the whether ex-Bertha will affect the UK can be found in our news release

A Tropical Storm called Bertha, which is currently in situated off the east coast of the US, could head towards Europe over the next week – so what’s the outlook?

Forecast tracks for Bertha, which was a hurricane but has now been downgraded to a tropical storm, suggest it will head north – staying offshore from the eastern coast of the US before turning to track east across the Atlantic.

Forecast track for Bertha from StormTracker shows it heading north off the east coast of the US before turning east.

Forecast track for Bertha from StormTracker shows it heading north off the east coast of the US before turning east.

While all forecast models suggest the storm will head in the general direction of UK and continental Europe, there remains a lot of uncertainty about exactly what it will do.

One certainty is that as the storm heads north away from the very warm seas which drive its power, it will lose strength and become what’s known as an extra-tropical storm – so we won’t be seeing a ‘hurricane in Europe’, but there is a chance we could see a fairly active summer storm.

The development of hurricanes and extra tropical storms can present complexities for meteorologists, and Bertha is a good example of that.

Here at the Met Office we use several world-leading forecast models as well as our own, and this gives an indication of how certain a forecast is. If all the models agree, there’s higher certainty, if they diverge, we know the atmosphere is finely balanced and there are several possible outcomes.

Satellite image of Bertha in the Caribbean taken at 11.45am on Monday, 4 August 2014 (Picture from NOAA)

Satellite image of Bertha in the Caribbean taken at 11.45am on Monday, 4 August 2014 (Picture from NOAA)

In the case of Bertha each of the models we use gives a very different picture of what the storm will do. This ranges from Bertha heading towards France as a weak feature which will completely miss the UK, to it arriving as a fairly active summer storm.

In terms of timing, there’s also a spread of possibilities – but it looks likely that the earliest Bertha would affect the UK would be on Sunday or into the start of next week.

As time progresses, different models normally come more in to line with each other and uncertainty decreases. The Met Office will be keeping an eye on how this situation develops over the next few days to give everyone in the UK the best advice on what Bertha is likely to do.

Given the time of year and the potential heavy rain, strong winds and large waves Bertha could bring if it does head to the UK, we’d advise everyone to stay up to date with the latest forecasts and warnings from the Met Office over the next few days.

You can also see the forecast track for Bertha and other tropical storms on our StormTracker pages.

NOTE – story updated to reflect Bertha’s status after being downgraded to a tropical storm.





Lightning strikes and heavy rain over the weekend

21 07 2014

Parts of the UK saw some very heavy downpours over the weekend, as thunderstorms caused disruption in some regions.

Westonbirt in Gloucestershire saw the most rain with 79mm over the weekend, more than its July full-month average of 59.3mm. Within that total, 34.2mm fell in just an hour Saturday afternoon – with some localised flash flooding as a result.

A rain gauge at Norwich airport saw the highest hourly-rainfall total, with 45.8mm falling between 3pm and 4pm on Sunday – this is close to its full month July average of 50.4mm.

Numerous other spots saw some high rainfall totals, particularly in eastern areas. Below you can see some of the highest recorded hourly and overall rainfall totals from the weekend.

It’s possible that some locations not included in the list saw heavy rain, but thundery downpours can be very localised – sometimes just a few hundred metres across.

This means that they can miss our rain gauge network, but you can explore rainfall totals from our Weather Observations Website (WOW) which has information supplied by observers all over the UK.

As we forecast on Friday, some locations avoided the storms altogether and saw prolonged fine weather over the weekend.

Nick Grahame, chief meteorologist at the Met Office, said: “The ‘Spanish Plume’ event we were forecasting led to some very intense thunderstorms over the weekend, with hourly and overall rainfall totals in line with our expectations.

“As we’d been highlighting in our forecasts, these storms can be very localised and that means some places avoided the storms altogether and saw a good deal of fine weather. It really highlights how events such as this can see some places with fairly severe impacts, while other places – sometimes quite nearby – can see no impacts at all.”

48-Hour Rainfall Totals from 2100HRS on 18 July to 2100HRS on 20 July 2014:

STATION LOCATION COUNTY RAINFALL (mm)
WESTONBIRT GLOUCESTERSHIRE 79
NORWICH AIRPORT NORFOLK 62.2
SHOEBURYNESS, LANDWICK ESSEX 48.6
PERSHORE COLLEGE HEREFORD & WORCESTER 45.6
PERSHORE HEREFORD & WORCESTER 39
ASTWOOD BANK HEREFORD & WORCESTER 35.6
KEELE STAFFORDSHIRE 32.4
ROCHDALE GREATER MANCHESTER 32
NEWPORT (SALOP) SHROPSHIRE 31
NOTTINGHAM, WATNALL NOTTINGHAMSHIRE 29.2

Highest hourly rainfall totals from the weekend:

DATE/TIME STATION LOCATION COUNTY RAINFALL (mm)
20/07/2014 15:00 NORWICH AIRPORT NORFOLK 45.8
19/07/2014 09:00 WESTONBIRT GLOUCESTERSHIRE 34.2
20/07/2014 17:00 MONKS WOOD CAMBRIDGESHIRE 22.8
19/07/2014 16:00 MARKET BOSWORTH LEICESTERSHIRE 15.8
19/07/2014 06:00 LIBANUS POWYS 15

This video shows the storms and lightning strikes as they developed over Spain and France and moved north across the UK.

In total the UK are saw 62,277 lightning strikes between 9am on Thursday 17 July and 9am on Monday 21 July 2014





Rain totals for 19th July 2014

20 07 2014

As forecast there were severe thunderstorms across the UK on the 19th July bringing heavy rain and gusty winds. See the tables below for the largest rain totals across the UK.  Gloucestershire recorded the highest rainfall with 66mm between 6am and 6pm yesterday, the counties monthly average rainfall is 60.6mm.

The Heat-health watch put in place in parts of southern and eastern England in conjunction with Public Health England has now been downgraded. Temperatures in parts of the area covered topped 28C during 19 July, see table below.

Today, 20 July, temperatures are expected to reach low to mid 20’s across central, south and south east of England, with London seeing around 27C.  Northern England will reach mid to high teens and Scotland and Northern Ireland mid to low teens.

More thundery downpours are expected to develop today over some eastern and central parts of the UK.  A yellow, be aware, weather warning for rain is in place for the areas likely to be affected. Not everywhere will see a storm but where they do occur, torrential downpours are possible with lightning, hail and strong gusts of wind. The areas most likely to be affected are across eastern and southeastern England.

Many places will have a good deal of fine and very warm weather this working week although there is the risk of some heavy showers in parts of the south and west later in the week.

 

UK MAX TEMPERATURE 19 JULY 2014
TIME SITE NAME AREA MAX TEMP (Celsius)
16:22 London St Jamess Park GREATER LONDON 28.5
15:13 Northolt GREATER LONDON 28.4
15:22 Heathrow GREATER LONDON 28.3
15:59 Santon Downham SUFFOLK 28.3
13:29 Gravesend, Broadness KENT 28.1
16:51 Cambridge NIAB CAMBRIDGESHIRE 27.7
15:49 Marham NORFOLK 27.7
13:55 Hampton W Wks GREATER LONDON 27.6
16:52 Writtle ESSEX 27.6
14:51 Frittenden KENT 27.5

 

 

12hr UK RAINFALL 19 JULY
SITE NAME AREA PRECIP. (MM)
WESTONBIRT GLOUCESTERSHIRE 66.0
PERSHORE COLLEGE HEREFORD & WORCESTER 36.4
PERSHORE HEREFORD & WORCESTER 30.8
NEWPORT (SALOP) SHROPSHIRE 29.4
KEELE STAFFORDSHIRE 28.2
ASTWOOD BANK HEREFORD & WORCESTER 27.6
NOTTINGHAM, WATNALL NOTTINGHAMSHIRE 26.0
LIBANUS POWYS 25.8
NANTWICH, REASEHEATH HALL CHESHIRE 22.6
MARKET BOSWORTH, BOSWORTH PARK LEICESTERSHIRE 22.6




The Met Office’s outlook for UK winter 2013-14

21 02 2014

There are some headlines in the media today discussing the Met Office long range forecast for this winter.

Firstly it’s important to remember that it’s our short and medium term forecasts that are relied on by emergency responders to help them manage the impacts of severe weather.

The Met Office’s five-day forecasts and severe weather warnings have provided excellent guidance throughout the period of exceptionally stormy and wet weather we have experienced this winter. This advice has helped everyone from the emergency services, to government organisations and the public plan ahead for the conditions we’ve seen.

The news stories are based on information taken from our three month outlook for contingency planners, issued at the end of November 2013 so, what can our three month outlooks tell us?

These outlooks are not like our other forecasts because, as we have discussed previously, it’s not currently scientifically possible to provide a detailed forecast over these long timescales.

Instead, the outlook assesses the level of risk connected to five different scenarios for both temperature and rain/snowfall for the UK as a whole; they do not mention specific areas such as the West Country or the Somerset Levels. It’s a bit like the science-equivalent of factoring the odds on a horse race.

However, as with any horse race, it’s always possible that the favourite won’t win – so these probability scenarios have to be used in the right context. This is why they’re useful for contingency planners who plan ahead based on risk, but not that useful for the general public.





January weather summary

14 02 2014

January saw a succession of weather systems tracking across the UK from the Atlantic which brought high winds, at times gale force, and persistent rain to the country. This extended a sequence of deep lows that began in mid-December. The worst of these were over by the 7th to give some brief respite, but rain continued through the remainder of the month with very few dry days. For the period from 12th December to the end of January some stations in the south of England had recorded over five months worth of rainfall.

The UK mean temperature for January was 4.8 °C, which is 1.1 °C above the 1981-2010 average. The UK overall received 151% of average rainfall making it the third wettest in the series. A broad region from east Devon to Kent and up to the central midlands received well in excess of 200 % and some more localised regions were closer to three times the average. Visit our climate section for a full written summary of the month.

Our infographic and video provide a summary of the weather throughout January:

14_0062-jan-summary-infog








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