Cold snap expected

3 12 2013

The UK is going to see a very short, sharp, cold snap.  From Wednesday night (4th Dec) into Thursday morning (5th Dec) Scotland, northern England and Northern Ireland will see some strong winds, while Scotland will see some wintry showers and snow.  However temperatures will return to normal as we head through the weekend, and be more in line with what should be expected for December.

A rapidly deepening Atlantic depression is expected to move in an easterly direction to the north of Scotland bringing westerly gales, with gusts of 60 to 70 mph extending southwards across northern and some central parts of the UK on Wednesday night and Thursday.  Northern Scotland could see gusts of 80mph, and potentially 90mph for a time.

Because of this the Met Office has issued a Yellow Severe Weather Warning for strong winds. The public should be aware of possible disruption to travel, especially across Scotland, parts of Northern Ireland and Northern England.

The winds are expected to veer northerly and bring the colder arctic air southwards across northern areas before easing into Friday. The winds could exacerbate high tides and may increase the risk of coastal flooding in the Northern and Western Isles and along the East Coast of England.

A Yellow warning for snow is also in place. It runs from 6am Thursday to 12 noon on Friday, covering the northern half of Scotland, snow showers are expected to be most frequent across the Northern Isles, the North Highlands and northern Aberdeenshire.  Low laying areas could see 2 – 5cms of snow and higher altitudes 10 – 20cms. In addition the strong winds could lead to some drifting of snow and possibly blizzard conditions on higher ground.  Icy conditions may also develop on some roads across Scotland on Thursday night and Friday morning.

This winter storm is not expected to be as powerful as those in January 2012 and December 2011

This is expected to be a short-lived cold snap, with temperatures quickly recovering to near normal over the weekend.

Our video explains what to do during a Yellow warning for wind. You can also download a weather warnings widget for your website.





Winter Forecasting – Responding to the headlines

12 10 2013

Once again it is the season for speculation and big headlines regarding what the weather will do over the winter period. The front page of the Daily Express today claims: ‘Worst winter for decades: Record-breaking snow predicted for November’.

We saw similar headlines last year and instead winter 12/13 ended up being only the 43rd coldest on record with an average temperature of 3.3C and flooding until the turn of the year.

What the Daily Express has failed to explain to its readers is that there is absolutely no certainty about what weather the UK will see over the winter period. The science simply does not exist to make detailed, long-term forecasts for temperature and snowfall even for the end of November, let alone for the winter period, which does not officially start until 1 December.

While we have seen a return to more normal, cooler temperatures for this time of year, this is no indication of what we can expect over the next four months with regards to temperatures and when we might see snow. It is far too early to tell.

Ultimately, we’re heading into winter and it is perfectly possible that we will see the whole range of weather that we get in winter at some point over the coming months, including snow and freezing temperatures, but also heavy rain, windy weather and mild conditions too.

Our five day forecasts and warnings will provide you with the best possible guidance on any periods of cold weather, frost or the likelihood of snow, giving detailed local information across the UK to help you make the most of the weather over the coming months.





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:





Spring swing brings colder weather and snow

7 03 2013

Frosty fence

We’ve had some very mild conditions this week with welcome sunshine pushing temperatures into the high teens. However, in a classic spring swing, colder weather is on the way as we head into the weekend.

By Saturday, we will see a return of easterly winds which will bring in much colder air from Scandinavia and Eastern Europe. Snow is expected across some eastern parts of the country over the weekend. By the start of next week, most of the UK will see daytime highs in low single figures with some frosty and icy nights.

So how unusual is it to see cold weather and snow in March?

The UK’s weather is very much at the mercy of where our winds come from, and throughout spring we can see sudden swings in the weather conditions. If we look back to last year we had very high temperatures at the end of March as the UK was under the influence of high pressure and light south-easterly winds. This year, this week’s south-easterly winds are now giving way to colder easterlies.

What about snow?

Statistics show that snow is more likely in March than around Christmas. As we know, heat from the sun increases as we head towards summer and this can lead to some interesting weather in March. With more heat from the sun the ground warms up more quickly and gives very unstable air, which can lead to a greater number of showers. Warmer air also holds more moisture so showers can give heavier rainfall. If this combines with cold air we can potentially see some heavy snowfall. However, easterly winds tend to be dry and so substantial snow fall is not expected over the next week.

As always, the Met Office will be working with different agencies to keep Britain on the move, and to keep people safe and well during periods of cold weather. The latest forecasts and warnings can be found online, through our mobile apps and through TV and radio broadcasts.





It’s cold but why is there no frost?

25 02 2013

There’s no denying that we have seen some cold weather this winter with plenty of frost, ice and in many cases, snow. However, the last week has been cold – arguably perhaps feeling colder than any other time this winter – but we haven’t seen any evidence of this on the ground in the way of frost. So how is this possible?

For a classic frosty night we need a few ingredients: low temperatures, clear skies, calm winds and moisture. A clear, calm night gives excellent radiation conditions – by this we mean that the heat absorbed by the Earth’s surface during the day escapes readily back into space and allows temperatures to fall. If the temperature falls to the dew point (the temperature to which air must cool for it to become saturated with water vapour) moisture will condense and form droplets on the ground’s surface. When temperatures fall below freezing the droplets freeze and we get frost.

So what about the last few days? They have been cold but there hasn’t really been any prolonged or hard frost. How come? Well, much of Scotland and Northern Ireland has had the required ingredients and been frosty, but the rest of the UK has only had low temperatures. Much of England and Wales have seen a fair amount of cloud and some brisk winds.

25th Feb 2013 crop

Surface pressure chart from 25 February 2013

Cloud acts as a blanket and although temperatures have fallen during the night-time, cloud cover has stopped them falling well below freezing and therefore made it difficult for a thick frost to form. The wind is also important as it mixes the lower part of our atmosphere. Rather than having cold air pooling in one place and causing low temperatures, the wind can bring less cold air from another location or even bring it down from the upper atmosphere. This also helps to keep temperatures from falling too low. However, easterly winds this week have certainly made it feel very cold indeed!

25 Feb vis pic

Visible satellite image from 25 February 2013

Lastly, the air near the surface has been relatively dry. This is important because it means the temperature of the air must fall very low in order to reach its dew point. The cloud and wind has stopped this from happening easily and therefore reduced the risk of frost.

Cold weather, then, brings lots of different tastes of winter, especially to the UK, and we have seen nearly all of them this season. More information on all types of weather can be found here.





Cold weather across UK

22 02 2013

The start of this week was relatively mild and sunny but we have seen a change to colder and cloudier weather during the course of the week.

20081219_frost_fog

High pressure became established to the north-east of the UK and this dragged in colder air from Scandinavia. It took some time for the cold air to filter across the whole of the UK but over the last couple of days daytime temperatures struggled to rise to 3 °C in some places. Brisk winds across England and Wales made it feel much colder, and we saw a few snow showers across eastern parts of the country.

Will Lang, Met Office Chief Forecaster, said: “This is a different taste of winter to the snow and ice we have seen of late. These largely dry, settled and cold conditions may not be as disruptive to travel but they do present concerns surrounding the health and well being of the elderly and vulnerable.”

The Met Office issued a level 3 Cold Weather Alert in light of the widespread and prolonged cold conditions. These alerts give advance warning of adverse weather conditions, which enable people to take extra precautions to keep safe and well.

A Department of Health spokesperson said: “Severe cold weather can be dangerous, especially for the very young or very old or those with chronic disease. You can find advice on how to reduce your risk or that of somebody you know on the NHS Choices website, ringing NHS Direct on 0845 46 47 or contacting your local GP or pharmacist.

“The NHS is well prepared for the winter and we are providing an extra £330 million to the NHS and social care services to help cope with the added pressure that the winter brings.”

With high pressure remaining in place, cold and largely settled weather looks set to remain across the UK until the end of February at least, and you can find the latest information from our forecasts and warnings, our mobile apps and through broadcasts on TV and radio.





Infographic: what to do when it snows

22 01 2013

With further warnings for snow in the UK our latest infographic covers what to do before, during and after snow fall.

Infographic what to do when it snows

See our website for the latest severe weather warnings. To find out more about when warnings are issued and what they mean see our guide to warnings.





Latest UK snow depths Monday 21 January

21 01 2013

Following further snow yesterday in the central and eastern areas of the country, snow depths over the UK were as follows at 9 am this morning:

Location Area Elevation Snow depth (cm)
Albemarle              Northumberland       142 19
Lough Fea              Londonderry          225 19
Sennybridge     Powys                307 18
Redesdale Camp         Northumberland       211 18
Little Rissington      Gloucestershire      210 17
Wittering              Cambridgeshire       73 16
Bingley         West Yorkshire       262 15
Waddington             Lincolnshire         68 13
Wattisham              Suffolk              89 13
Dunkeswell Aerodrome   Devon                252 13
Nottingham, Watnall    Nottinghamshire      117 12
Gutersloh              Germany              70 12
Cranwell               Lincolnshire         63 12
Coleshill              Warwickshire         96 12
Leek, Thorncliffe      Staffordshire        298 11
Liscombe               Somerset             348 11
Spadeadam   Cumbria              285 10
Filton                 Avon                 59 10
Middle Wallop          Hampshire            90 10
Aboyne    Aberdeenshire        140 10
Aviemore               Inverness-Shire      228 9
Eskdalemuir            Dumfriesshire        236 9
Marham                 Norfolk              21 9
Coningsby              Lincolnshire         6 9
Larkhill               Wiltshire            132 8
Scampton               Lincolnshire         57 8
Brize Norton           Oxfordshire          82 8
Hereford, Credenhill   Hereford & Worcester 76 7
Valley                 Gwynedd              10 7
Bedford                Bedfordshire         85 7
Shawbury               Shropshire           72 7
Charlwood              Surrey               67 6
Manston                Kent                 49 6
Boscombe Down          Wiltshire            126 6
Northolt               Greater London       33 6
Glenanne   Armagh               161 5
Heathrow               Greater London       25 5
Herstmonceux, West End East Sussex          52 5
Dyce                   Aberdeenshire        65 4
Hurn                   Dorset               10 4
Leeming                North Yorkshire      33 3
Linton On Ouse         North Yorkshire      14 3
Leconfield             Humberside           7 3
Shap                   Cumbria              252 3
Hawarden Airport       Clwyd                11 3
Rostherne   Cheshire             35 3
Odiham                 Hampshire            118 3
Benson                 Oxfordshire          57 2
Strathallan Airfield   Perthshire           35 2
Drumalbin              Lanarkshire          245 2
St Athan               South Glamorgan      49 2
Camborne               Cornwall             86.85 1
cloud cover over uk

Satellite image of the UK this morning, cloud is covering the UK which prevents us from seeing the areas covered by snowfall.

Further snow is forecast in some parts, and ice continues to be a hazard in areas that have already seen snow. Keep up to date with the latest forecasts and warnings for your area on our website.





Overnight lows and the latest snow depths

19 01 2013

As forecast temperatures fell well below zero across the UK last night and the heaviest of the snow started to ease in most areas.

The lowest temperature recorded at a Met Office observing station was Edinburgh, Gorgarbank, at -4.3 C and at 9am this morning the deepest snow cover was 27 cm at Lough Fea, Londonderry.

Lowest temperatures overnight 18 to 19 January 2013:

Location Area Temperature (Celsius)
Edinburgh Gogarbank                 Midlothian           -4.3
Lake Vyrnwy             Powys                -4.3
Pennerley                           Shropshire           -4.0
Tredegar Bryn Bach Park     Gwent                -3.5
Crosby                              Merseyside           -3.4
Libanus                             Powys                -3.4
Leek, Thorncliffe                   Staffordshire        -3.3
Little Rissington                   Gloucestershire      -3.3
Sennybridge                    Powys                -3.2
Carterhouse                         Roxburghshire        -3.1
Salsburgh                           Lanarkshire          -3.1
Keele                               Staffordshire        -3
Emley Moor                     West Yorkshire       -2.9
Astwood Bank                        Hereford & Worcester -2.8
Winterbourne                  West midlands        -2.8
Aviemore                            Inverness-shire      -2.7
Bingley                        West Yorkshire       -2.7
Liscombe                            Somerset             -2.7
Pateley Bridge Ravens Nest          North Yorkshire      -2.7
Spadeadam                     Cumbria              -2.7

Snow depths at 9am Saturday 19 January 2012:

Location Area Elevation Snow depth (cm)
Lough Fea              Londonderry          225 27
Sennybridge       Powys                307 22
Little Rissington      Gloucestershire      210 20
Loftus                 Cleveland            158 16
Liscombe               Somerset             348 16
Filton                 Avon                 59 16
Brize Norton           Oxfordshire          82 12
Hereford, Credenhill   Hereford & Worcester 76 11
Nottingham, Watnall    Nottinghamshire      117 11
Larkhill               Wiltshire            132 11
Albemarle              Northumberland       142 10
Cranwell               Lincolnshire         63 10
Benson                 Oxfordshire          57 10
Leconfield             Humberside           7 10
Redesdale Camp         Northumberland       211 9
Middle Wallop          Hampshire            90 9
Boscombe Down          Wiltshire            126 8
Aboyne            Aberdeenshire        140 8
Wittering              Cambridgeshire       73 8
Coningsby              Lincolnshire         6 7
Leek, Thorncliffe      Staffordshire        298 7
Northolt               Greater London       33 7
Leeming                North Yorkshire      33 6
Marham                 Norfolk              21 6
Shawbury               Shropshire           72 6
Bingley          West Yorkshire       262 6
Waddington             Lincolnshire         68 6
Odiham                 Hampshire            118 6
Eskdalemuir            Dumfriesshire        236 5
Hurn                   Dorset               10 5
Scampton               Lincolnshire         57 5
Charlwood              Surrey               67 5
Coleshill              Warwickshire         96 5
Wattisham              Suffolk              89 4
Boulmer                Northumberland       23 4
Dyce                   Aberdeenshire        65 4
Bedford                Bedfordshire         85 3
Trawsgoed              Dyfed                63 3
Church Fenton          North Yorkshire      8 3
Linton on Ouse         North Yorkshire      14 3
Heathrow               Greater London       25 3
Edinburgh, Gogarbank   Midlothian           57 3
St Athan               South Glamorgan      49 3
Herstmonceux, West End East Sussex          52 2

The cold weather is set to continue for the remainder of the weekend and ice is expected to be a major hazard, keep up to date with your local forecast for the latest update.





How the ‘pest from the west’ will beat the ‘Beast from the East’

10 12 2012

There was much talk at the end of last week about the ‘Beast from the East’ being set to bring some cold and wintry conditions to the UK this week. However, the balance in the atmosphere has changed and the current cold weather looks set to be replaced by milder, wetter weather by the end of the week.

So what has happened in the atmosphere to bring such a dramatic change in the forecast?

As expected at the end of last week, we do have winds blowing from the northeast, tracking across the North Sea from Scandinavia and bringing scattered showers to eastern parts of the country as shown on the chart below. So, we can expect a couple of days of cold and mainly dry weather with a few showers in eastern counties, sharp frosts and some freezing fog at night.

Actual chart Monday 10 December 2012

The atmosphere is always finely balanced and for the ‘Beast from the East’ to really ‘bear’ its teeth the high pressure area over Greenland would need to develop and draw the wind in from Europe. It now looks like this is not going to happen and instead the depression to the west of the UK is going to win the atmospheric battle and bring heavy rain and strong winds to us all from Thursday.

Met Office forecasters will be monitoring this developing weather situation throughout the week and have already issued warnings to give advanced notice of the potential impacts from the heavy rain in some parts of the country.

The latest forecasts and warnings can be found on the Met Office website, on our mobile apps and through TV and radio broadcasts on the BBC and ITV.








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