Statistics for winter so far

11 02 2014

As the unsettled UK weather continues this week, the Met Office’s National Climate Information Centre have looked at statistics for this winter so far (from 1 December to 10 February).

These add to previous facts and figures we put out earlier this week, and show a picture of continuing exceptional rainfall across many areas.

Looking at regions around the UK, these provisional figures suggest the region of SE and Central S England has already exceeded its record winter rainfall in the series back to 1910. It is currently at 439.2mm*, less than 2mm above the previous record set in 1915 with 437.1mm of rain.

For the UK as a whole, and also for Wales, both are fairly close to their respective record wettest winter levels in the national series dating back to 1910. Average rainfall for the rest of the month would likely see those records broken.

All countries across the UK have already exceeded their typical average rainfall for the whole winter (according to the 1981-2010 long-term averages). Normally at this stage of the season, you’d expect to have seen only around 80% of that whole season average.

All areas are also on target for a significantly wetter than average winter, with typically around 130-160% of normal rainfall if we get average rainfall for the rest of February.

All countries and areas are also on target for a warmer than average winter.

Current record wettest winters:

Country Year Rainfall Winter 2014 to date*
UK 1995 485.1mm 429.2mm
ENGLAND 1915 392.7mm 328.0mm
WALES 1995 684.1mm 618.7mm
SCOTLAND 1995 649.5mm 558.5mm
NORTHERN IRELAND 1994 489.7mm 360.0mm

 

*These are provisional figures from 1 December 2013 to 10 February 2014 and could change after final quality control checks on data.





UK’s exceptional weather in context

6 02 2014

As the UK’s run of exceptionally wet and stormy weather continues, the Met Office’s National Climate Information Centre has looked at how the last two months compare in the historical records.

Here’s some facts and figures for the weather we’ve seen through December and January:

For the UK

  • For the UK, December was provisionally the equal-fifth wettest December in the national series dating back to 1910 and January was the third wettest January in the same record. When the two months are combined, it is provisionally the wettest December and January in the series.
  • There were more days of rain (any day with more than 1mm of rainfall) for the UK in January than for any other month in a series dating back to 1961, with 23 days.
  • It was the windiest December for the UK in records back to 1969, based on the occurrence of winds in excess 60 kts (69mph).

England and Wales

  • Looking at the England and Wales Precipitation series, which dates back to 1766, it has been the wettest December to January since 1876/1877 and the 2nd wettest overall in the series.

Scotland

  • December was the wettest calendar month on record for Scotland in the series to 1910.
  • For eastern Scotland, December and January combined was provisionally the wettest two month (any-month) period in the same series.

Southern England

  • There have been very few dry days in this area since 12 December and regional statistics suggest that this is one of, if not the most, exceptional periods of winter rainfall in at least 248 years.
  • Despite the rainfall being concentrated in the second half of the month it was the wettest December for south east England since 1959.
  • January was the wettest January for the south England region in the national series dating back to 1910, and the wettest calendar month for the south east region in the same series by a huge margin.
  • The two-month total of 372.2mm for the southeast and central southern England region is the wettest any 2-month period in the series from 1910 .
  • From 12th December to 31st January parts of south England recorded over five months worth of rainfall (based on average January rainfall for the region).

You can see more statistics on recent weather and through the historical records on our UK climate pages.

Full month provisional statistics from January 2014:

Mean Temperature Sunshine hours Rainfall  
January
Actual Diff from Avg Actual % of Avg Actual % of Avg
  degC degC hours % mm %
UK 4.8 1.1 44.8 95 183.8 151
England 5.4 1.3 57.3 106 158.2 191
Wales 5.3 1.2 38.0 78 269.0 171
Scotland 3.5 0.9 27.2 76 205.3 116
N Ireland 4.5 0.3 37.3 84 170.7 147




Wind gusts and rainfall totals 4-5th February 2014

5 02 2014

Last night another major Atlantic depression affected the UK, bringing further heavy rain and severe gales.

Here are some of the highest gusts of wind and rainfall totals recorded at Met Office observing stations between 3pm yesterday and 8am today.

Location Area Height (m) Max gust (mph)
SCILLY: ST MARYS AIRPORT ISLES OF SCILLY 31 92
BERRY HEAD DEVON 58 91
CULDROSE CORNWALL 76 76
WIGHT: NEEDLES OLD BATTERY ISLE OF WIGHT 80 71
PLYMOUTH, MOUNTBATTEN DEVON 50 71
ABERPORTH DYFED 133 70
CARDINHAM, BODMIN CORNWALL 200 70
ISLE OF PORTLAND DORSET 52 70
ST BEES HEAD NO 2 CUMBRIA 124 68
CAMBORNE CORNWALL 87 67
CAPEL CURIG NO 3 GWYNEDD 216 66
GUERNSEY: AIRPORT GUERNSEY 101 64
ORLOCK HEAD DOWN 35 64
MILFORD HAVEN DYFED 44 63
POINT OF AYRE ISLE OF MAN 9 62
NORTH WYKE DEVON 177 61
JERSEY: AIRPORT JERSEY 84 61
PEMBREY SANDS DYFED 3 61
DUNKESWELL AERODROME DEVON 252 60
MUMBLES HEAD WEST GLAMORGAN 43 60
Location Area Rainfall (mm)
NORTH WYKE DEVON 33.4
CAMBORNE CORNWALL 25.2
DUNKESWELL AERODROME DEVON 24.6
CARDINHAM, BODMIN CORNWALL 24.4
BANAGHER, CAUGH HILL LONDONDERRY 24.0
KATESBRIDGE DOWN 23.8
HIGH WYCOMBE, HQAIR BUCKINGHAMSHIRE 21.4
LISCOMBE SOMERSET 21.4
EXETER AIRPORT DEVON 21.2
DALWHINNIE INVERNESS-SHIRE 18.6
ALICE HOLT LODGE HAMPSHIRE 18.4
OKEHAMPTON DEVON 17.9
CULDROSE CORNWALL 17.6
BENSON OXFORDSHIRE 17.6
ODIHAM HAMPSHIRE 17.2
BUDE CORNWALL 17.0
CARTERHOUSE ROXBURGHSHIRE 17.0
CHARLWOOD SURREY 17.0
UPPER LAMBOURN BERKSHIRE 16.8
TREDEGAR GWENT 16.6

Further severe gales and heavy rain are expected over the next few days and everyone is advised to stay up to date with the latest Met Office forecasts and National Severe Weather Warnings and be prepared that the weather may change or worsen, leading to disruption of your plans.





Saturday’s squally weather and reports of tornadoes

27 01 2014

On Saturday we saw a number of heavy rain showers group together in what’s known as a ‘squall line’ – a narrow band of thunderstorms, intense rain, hail, and frequent lightning accompanied by brief but very strong gusts of wind and possibly tornadoes.

Radar image showing the narrow band of showers moving across the UK.

Radar image showing the narrow band of showers moving across the UK.

This squall line swept across Wales and then moved south east across southern parts of England – bringing about 6mm of rain to places in a very short period of time with gusts of wind of around 60mph or more in places.

It  also had the characteristics of a cold front, with the temperature ahead of it being around 11°C, falling to 7°C once the squall line had passed.

There have been reports of possible weak tornadoes from some locations, however it’s hard to verify them without pictures or footage because these features are generally too small to be picked up by satellites or weather observation equipment.

It’s also worth noting that squally winds can often be mistaken for tornadoes because these gusts can be sudden and strong – potentially causing very localised damage.

You can see more information on tornadoes and how they form on our website.





UK Weather: How stormy has it been and why?

3 01 2014

Since the start of December the UK has seen a prolonged period of particularly unsettled weather, with a series of storms tracking in off the Atlantic bringing strong winds and heavy rain.

The windiest month since 1993

In order to compare the recent spell with the numerous stormy periods of weather in the past the Met Office’s National Climate Information Centre has done an analysis of the number of weather stations in the UK which have registered winds over certain thresholds since the start of December.

This measure suggests that December 2013 is the stormiest December in records dating back to 1969 and is one of the windiest calendar months for the UK since January 1993.

December was also a very wet month across the UK, particularly in Scotland where it was the wettest December and wettest month overall in the records dating back to 1910.

But why has this been the case?

Storms are expected in winter

First of all, we do generally expect to see stormy conditions in winter months. This is because we see a particularly big difference in temperature between the cold air in the Arctic and the warm air in the tropics at this time of year.

This contrast in temperatures means we see a strong jet stream, which is a narrow band of fast moving winds high up in the atmosphere.

The jet stream can guide storms as they come across the Atlantic, and it has been sitting in the right place to bring those storms to the UK over the past few weeks.

There’s also a close link between the jet stream and storms. The jet stream can add to the strength of storms, but then storms can also increase the strength of the jet stream. This positive feedback means storms can often cluster together over a period of time.

But why has it been particularly stormy?

Even accounting for the fact that it’s winter, the jet stream has been particularly strong over the past few weeks – but why is this the case?

It’s partly due to particularly warm and cold air being squeezed together in the mid-latitudes, where the UK sits. This could be due to nothing more than the natural variability which governs Atlantic weather.

However, looking at the broader picture, there is one factor which could increase the risk of a stormy start to winter and this is called the quasi-biennial oscillation (QBO for short).

This is a cycle, discovered by the Met Office in 1959, which involves a narrow band of fast moving winds (much like our jet stream) which sits about 15 miles up over the equator. The cycle sees these winds flip from easterly to westerly roughly every 14 months.

In 1975 Met Office researchers discovered that when the QBO is in its westerly phase, it tends to increase the westerlies in our own jet stream – meaning there’s a higher risk of a stronger, more persistent jet stream with more vigorous Atlantic storms. It has been in its westerly phase since early 2013 and we expect it to decline over the next few months.

This is just one factor among many, however, which needs to be considered – so it doesn’t mean that the westerly phase of the QBO will always bring us stormy winters.

What about climate change?

Climate models provide a broad range of projections about changes in storm track and frequency of storms. While there’s currently no evidence to suggest that the UK is increasing in storminess, this is an active area of research under the national climate capability.





Updated Wind and Rainfall totals for 18th to 19th December

19 12 2013

As forecast there were severe gales and heavy rain overnight. See the tables below for the strongest low level gusts and the largest rain totals across the UK.

We are expecting more stormy weather over the coming days, with spells of heavy rain and gales affecting the UK – with the heaviest rain affecting the west and south west and strongest winds affecting the far north. Warnings for each individual spell of wet and windy weather will be issued when we are confident they will provide useful and accurate advice.

UK MAX HOURLY GUST SPEED 18TH DEC 1800HRS – 19TH DEC 0700HRS

SITE NAME AREA ELEVATION MAX GUST SPEED (MPH)
WIGHT: NEEDLES OLD BATTERY ISLE OF WIGHT 80 94
SOUTH UIST RANGE WESTERN ISLES 4 90
TIREE ARGYLL 9 87
PLYMOUTH, MOUNTBATTEN DEVON 50 85
CASTLEDERG TYRONE 49 84
PEMBREY SANDS DYFED 3 82
CAPEL CURIG NO 3 GWYNEDD 216 81
STORNOWAY AIRPORT WESTERN ISLES 15 77
ALTNAHARRA NO 2 SUTHERLAND 81 77
FAIR ISLE SHETLAND 57 76

24 HOUR UK RAINFALL TOTALS 18TH DEC 0700HRS – 19TH DEC 0700HRS

SITE NAME AREA PRECIP        AMOUNT ( MM)
TREDEGAR GWENT 38.4
CARDINHAM, BODMIN CORNWALL 35
WHITECHURCH DYFED 34.4
TYNDRUM PERTHSHIRE 32.2
LIBANUS POWYS 30.8
SHAP CUMBRIA 30.6
OKEHAMPTON, DEVON 30.6
KESWICK CUMBRIA 28.8
TULLOCH BRIDGE INVERNESS-SHIRE 27
BALA GWYNEDD 26.4




UPDATED: Wind and rainfall data 4 to 5 December 2013

5 12 2013

UPDATED TO INCLUDE LATEST WIND SPEEDS AS AT 3PM, 5 DECEMBER 2013

As forecast, there have been severe gales with widespread gusts of between 60 and 80mph across Scotland and northern parts of England. Some very high level mountain sites have reported speeds of over 140mph, but these are in very exposed areas and not representative of the winds most people have experienced.

UK MAX HOURLY GUST SPEED 4 DEC 1800HRS – 5 DEC 0600HRS
SITE NAME AREA ELEVATION MAX GUST SPEED (MPH)
ALTNAHARRA SUTHERLAND 81 93
LOCH GLASCARNOCH ROSS & CROMARTY 269 92
DRUMALBIN LANARKSHIRE 245 90
SOUTH UIST RANGE WESTERN ISLES 4 89
HIGH BRADFIELD SOUTH YORKSHIRE 395 87
EMLEY MOOR WEST YORKSHIRE 267 86
STORNOWAY AIRPORT WESTERN ISLES 15 85
ORLOCK HEAD DOWN 35 84
KINLOSS MORAY 5 83
SPADEADAM CUMBRIA 285 83
ESKDALEMUIR DUMFRIESSHIRE 236 83
SKYE: LUSA WESTERN ISLES 18 83
TIREE ARGYLL 9 82
DUNSTAFFNAGE ARGYLL 3 82
 MOUNTAIN SITES MAX GUST SPEED 4 DEC 1800HRS – 5 DEC 0600HRS
SITE NAME AREA ELEVATION MAX GUST SPEED (MPH)
AONACH MOR INVERNESS-SHIRE 1130 142
CAIRNWELL ABERDEENSHIRE 928 137
BEALACH NA BA ROSS & CROMARTY 773 116
GREAT DUN FELL CUMBRIA 847 113
GLEN OGLE PERTHSHIRE 564 106

It has been very wet in some areas overnight as well with 50.8mm of rain being recorded at Tyndrum, Perthshire and 42.4mm at Cluanie Inn, Ross & Cromarty.





Typhoon Haiyan makes landfall over the Philippines

8 11 2013

As predicted Typhoon Haiyan made landfall late yesterday evening (UK time) over the central Philippines.

Typhoon Haiyan will have caused catastrophic damage near the centre of its track through the Philippine islands of Samar, Leyte and Panay. In addition to the strong winds, the storm surge and heavy rain will also have caused major impacts in these regions. The typhoon is now moving out into the South China Sea. Over the next couple of days it is likely to lose some strength before making another landfall in northern parts of Vietnam on Sunday, although is still expected to be a typhoon.

Typhoon Haiyan at 2230 UTC on 07 November 2013 as it made landfall. Image from NOAA.

Typhoon Haiyan at 2230 UTC on 07 November 2013 as it made landfall. Image from NOAA.

At the time of landfall the estimated central pressure of the typhoon was 895 mb and sustained winds averaged over one minute estimated at 195 mph with higher gusts. These estimates are based on well attested satellite techniques, but without observations exactly in the path of the eye of the typhoon it is impossible to confirm their accuracy. However, this is likely to make Haiyan one of the most intense tropical cyclones to make landfall in history.

Forecast track of Typhoon Haiyan from the Japan Meteorological Agency. (http://www.jma.go.jp/en/typh/images/zooml/1330-00.png) NOAA.

Forecast track of Typhoon Haiyan from the Japan Meteorological Agency.

In 1969 Hurricane Camille made landfall over the southern USA with sustained winds near 190 mph and in 1935 a hurricane which passed over the Florida Keys had an observed central pressure of 892 mb.

In terms of all time records, Typhoon Tip in 1979 holds the record for the lowest pressure in a tropical cyclone measured at 870 mb and the strongest wind gust ever recorded in a tropical cyclone was 253 mph in Cyclone Olivia off the north-west coast of Australia in 1996. As things stand these records seem likely to remain for the time being.

Regional warnings for Typhoon Haiyan are produced by the Japanese Meteological Agency (JMA) and the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA). The Met Office routinely supplies predictions of typhoon 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 model data and guidance is also used by Project NOAH in part for warning the government and the Filipino population.

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 Unified Model and latest observed cloud cover and sea surface temperature. We also provide updates on current tropical storms via @metofficestorms on Twitter.





How powerful was Monday’s storm?

30 10 2013

The storm that swept across southern parts of the UK caused widespread disruption and included a gust of almost 100mph, but how does it compare to previous storms?

It’s not just the numbers

In terms of the severity of the winds, you don’t have to go far back to find a more powerful storm than this – in January 2012 we saw winds of over 100mph in Edinburgh for example.

There are two things that made this storm so significant. Firstly, the timing – arriving in October when the trees are in full leaf and therefore much more vulnerable to strong winds.

Secondly the track of this storm was key. Along the northern and western coasts of Scotland and northern Ireland winds of 70-80mph are not that exceptional because they are on the more usual track of Atlantic storms.

However, powerful Atlantic storms are seen much more rarely across southern parts of England and Wales – which means these areas are much more susceptible to strong winds.

All this combined meant that the storm had a significant impact – with fallen trees causing the majority of disruption.

Satellite image showing the storm tracking across the UK

Satellite image showing the storm tracking across the UK

When did we last see a storm like this?

With that in mind, to find a similar storm we’d have to look at those which affected southern parts of England at a time when leaves are still on the trees (likely to be autumn).

To find a storm of similar strength that fits these criteria you’d have to go back to 27 October 2002. That storm brought winds of similar, or higher speeds, affecting most of England and Wales, and leading to widespread impacts.

Where does Monday’s storm rank in the longer term records?

There are many different ways of comparing storms – from looking at the strongest gusts, to mean wind speeds, to the area affected or the severity of impacts.

The Met Office National Climate Information Centre (NCIC) looked at autumn storms in southern England over the past 40 years, analysing the number of weather stations across the region which recorded a gust of 60 knots (69mph) or more for each storm.

From this they put together the ranking below which suggests Monday’s storm was within the top 10 most powerful autumn storms in southern England in the past 40 years.

The storm of October 2002 comes top of this ranking – followed by the ‘Great Storm’ of 16 October 1987.

Mike Kendon, from the NCIC, said: “This is just one technique for analysing storms and doesn’t necessarily tell us how severe an impact any particular storm had. On 16 October 1987, the maximum gusts we saw were much more powerful than those seen in 2002, and it was those very powerful winds – of up to 115mph – which caused the majority of the damage.

“What our analysis does tell us is that Monday’s storm was certainly one of the most significant autumn storms for at least a decade in terms of its strength and its impacts – even if it’s not on a par with some of the most powerful or damaging storms we have seen in the UK’s historical records.”

DATE OF STORM

STATIONS WITH >69MPH GUST

27/10/2002

36

16/10/1987

28

28/10/1996

24

30/10/2000

21

11/11/1977

18

28/10/1989

18

28/10/2013

16

07/09/1974

14

24/10/1998

14

14/11/1977

13





Unsettled weather to come – but no repeat of ‘St Jude’ in sight

29 10 2013

There have been a few mentions in today’s media of another storm coming in for this weekend – with the Daily Express suggesting that a ‘new deadly storm’ is on the way.

It’s fair to say we are expecting a spell of unsettled autumnal weather over the next week, with some strong winds and heavy rain possible – but comparisons with the ‘St Jude’s Day storm’ (as some in the media have called it) are wide of the mark.

Currently forecasts suggest that we will see several low pressure systems affecting the country over the next week – which is a fairly typical picture for UK weather at this time of year.

These could bring gale force winds at times to some areas, but we don’t expect gusts to be anything like the exceptionally strong winds we saw on Monday. In fact, the winds are more likely to be similar to those we saw during the day last Sunday – the day before the big storm.

Of course, even gale force gusts do bring some risks and the Met Office will closely watch developments to assess any impacts.

The low pressure systems coming through over the next week are likely to lead to some rough seas and big waves around some coasts, as well as some heavy rain.

The Met Office, Environment Agency and Scottish Environment Protection Agency (SEPA) will be working together to monitor the risk of any impacts from these over the next few days.

Given the outlook for unsettled weather, we’d advise people to stay up to date with the latest forecasts and warnings from the Met Office and to sign up to receive free flood warnings from the Environment Agency and SEPA website.








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