Hurricane Joaquin lashes the Bahamas but will it hit the USA?

1 10 2015

In recent months attention has focused on the very active tropical cyclone season in the Pacific Ocean brought about primarily by the strong El Niño which has developed this year. Meanwhile, the Atlantic has been very quiet with most tropical storms remaining fairly weak and only two reaching hurricane strength until now.

However, Joaquin has become the third hurricane of the Atlantic season and the second to achieve ‘major’ status – category 3 or above on the Saffir-Simpson Hurricane Wind Scale. Joaquin is currently lashing the Bahamas with winds in excess of 100 mph near the centre of the hurricane. A storm surge of over two metres is possible and rainfall totals could be as high as 500 mm. Once the hurricane starts moving away from the islands the big question is whether it will make landfall over the US east coast.

Hurricane Joaquin at 1237 UTC on 01 October 2015 Image courtesy of the US Naval Research Laboratory [local copy at http://www-nwp/~frjh/tropicalcyclone/images/nhem15/joaquin_20151001_1237z.png]

Hurricane Joaquin at 1237 UTC on 01 October 2015
Image courtesy of the US Naval Research Laboratory

The forecasting conundrum

Joaquin is currently slow moving near the Bahamas and all computer models agree that a gradual turn north will happen in about two days time. However, beyond this point there is great uncertainty as to what will happen. Joaquin is being pulled in two directions. A developing trough of low pressure over the USA would act to pull Joaquin westwards towards the US coast. However, an area of low pressure to the east – including the remnants of Tropical Storm Ida – would act to pull Joaquin east away from the USA. The situation is finely balanced and any of several outcomes could happen.

One scenario is that Joaquin could make a turn north-westwards and make landfall near the Outer Banks of North Carolina at the weekend. Computer models are now mostly moving away from this as a likely outcome. Alternatively, Joaquin could take a mostly northwards track and reach New York and New England by early next week then continue up the eastern seaboard of Canada. Finally, a third scenario allows for the possibility that Joaquin could turn north-eastwards and avoid a US landfall altogether. We recommend that a close watch is kept on guidance issued by the National Hurricane Center in coming days for updates on which scenario is the most likely to occur.

Irrespective of whether or where Hurricane Joaquin makes landfall on the US east coast, large amounts of rain are expected in this area in the coming few days due to a slow-moving frontal zone. The impact of this will be exacerbated if Hurricane Joaquin does take a turn towards the USA in the next few days with further heavy rain accompanied by strong winds and a storm surge.

 Latest forecast track of Hurricane Joaquin from the National Hurricane Center

Latest forecast track of Hurricane Joaquin from the National Hurricane Center

Recent history of US landfalling hurricanes

Hurricane strikes on the USA have been fairly infrequent in recent years – particularly those at the stronger end of the scale. In 2014 Arthur crossed the Outer Banks of North Carolina as a category 2 hurricane. Going back to 2012, Isaac came ashore over Louisiana as a minimal category 1 hurricane. In 2011 Irene made landfall on the east coast of the USA also as a category 1 hurricane. The USA avoided hurricane strikes altogether in 2010 and 2009, but in 2008 three made landfall, the most significant of which was Hurricane Ike which caused a huge storm surge as it came ashore over Texas as a category 2 hurricane. However, you have to go back to 2005 to find the last ‘major’ hurricane strike on the USA (category 3 or above), when Hurricane Wilma hit Florida.

Hurricane Sandy (sometimes referred to as ‘Superstorm Sandy’) also caused much devastation to parts of the USA east coast in 2012. It is ranked as the second most costly hurricane in US history, although technically ceased to be a hurricane just prior to the time it made landfall.

Official warnings for the latest tropical cyclones in the Atlantic are produced 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. We also provide updates on current tropical storms via @metofficestorms on Twitter.

Will Joaquin affect the UK?

With the confidence around the exact track of Joaquin being so low, it is currently too early to tell if this system will affect the weather in the UK. There is, however, already high confidence that we will return to more autumnal and unsettled conditions across the UK early next week. Make sure you keep up-to-date with the Met Office five-day forecast.

Dry, sunny but cool September

30 09 2015

Two spells of settled weather during September have contributed to a rather dry and sunny but cool September.

Provisional statistics for the month show that after a wet end to August, September has been drier than average for much of the UK with figures up to the 28 September showing that there has been 53.3mm of rain, only 55% of the September average of 96.4mm.

Northern and western Scotland have been particularly dry with only 37% and 31% of the September average for rainfall having been recorded. In comparison, parts of eastern and southeast England have seen above average rainfall. Wales has seen 75mm of rain, 64% of average, while Northern Ireland recorded 51% of the September average for rainfall with a total of 47.1mm.

Many places have enjoyed a sunny month with 137 hours of sunshine recorded across the UK, this is 10% above the average for September.

However, despite the dry and sunny weather conditions, September has seen some rather cool days and nights. Mean temperatures across the UK up until the 28 September are 0.8C below normal with minimum temperatures across England and Wales around 1.5C below the September average. Five UK observing sites have already recorded their first frost of the season.

September 2015 rainfall amount

September 2015 rainfall amount

September 2015 sunshine anomaly

September 2015 sunshine anomaly












PROVISIONAL mean temperature sunshine duration precipitation
Sep-2015 Act Anm (8110) Act Anm (8110) Act Anm (8110)
degC degC hours % mm %
UK 11.9 -0.8 137.2 110 53.3 55
England 12.6 -1.1 152.5 111 52.8 76
Wales 11.8 -1.1 151.9 119 75.0 64
Scotland 10.8 -0.1 112.0 106 49.3 36
N Ireland 11.7 -0.7 113.9 100 47.1 51


The outlook for the first few days of October is for the fine, settled weather to continue before we see a transition towards more changeable weather next week with rain at times. Check out our five day forecast for more details.

Dry start to September for many

18 09 2015

You may think September has been a wet month so far but according to early provisional Met Office statistics, the month has started out drier and sunnier than average for many across the UK.

However the picture has been varied, some parts of southern and eastern England have already had over three quarters of their whole-month average rainfall for September. While northern and western areas have been drier, with little in the way of rain so far for much of Northern Ireland and Scotland away from eastern coasts.

Figures up to 16th September show there has been almost 30mm of rain across the UK, which is just 31% of the September average of 96mm. We would normally expect about half of the average monthly rainfall to have fallen by this point in the month. While there has been almost 72 hours of sunshine, 58% of the monthly average of 125 hours, with some north-western areas being especially sunny so far this month.

01 -16 Sept 2015 Rainfall Amount

01 -16 Sept 2015 Rainfall Amount

Looking at individual countries, Scotland has been the driest with almost 21mm of rain, 15% of average, followed by Northern Ireland with almost 24mm of rain, 26% of average. England is the wettest country so far with almost 34mm 49% of average.  There was a dry anticyclonic spell for the UK lasting from 5th until 11th, since then there have been some noticeable falls of rain.

The UK mean temperature so far has been 12.2C, which is 0.4C below the full-month average.

EARLY mean temperature sunshine duration precipitation
Sep-2015 Act Anm (8110) Act Anm (8110) Act Anm (8110)
degC degC hours % mm %
UK 12.2 -0.4 71.8 58 29.8 31
England 13.0 -0.8 78.2 57 33.8 49
Wales 12.3 -0.6 73.2 57 42.2 36
Scotland 11.0 0.1 63.6 61 20.9 15
N Ireland 12.2 -0.2 56.1 49 23.9 26


While these figures are interesting, they don’t tell us where the month will end up overall. A few days of wet or cold weather could drastically alter the statistics, so we’ll have to wait for the full-month figures before making any judgements.

Meanwhile this weekend is looking fine and dry, with good spells of sunshine for many on Saturday and many places seeing settled weather continuing well into Sunday evening. Check out our five day forecast for more details.

So what happened to our summer?

28 08 2015

Our Chief Scientist Professor Dame Julia Slingo OBE FRS reflects on this summer’s weather and what has influenced it:

No-one can deny that we have had a pretty disappointing summer with a lot of unsettled weather and only a few warm spells, especially through July and August. Our weather has been dominated by low pressure over and to the west of the country that has brought us periods of heavy rain from the south – what we call the Spanish Plume. So what has been happening?

If we look beyond our shores there have been some big changes in the global climate this year. El Niño is in full flight, disturbing weather patterns around the world. The low pressure that has dominated our weather is part of a pattern of waves in the jet stream around the world that has brought crippling heat waves to places like Poland and Japan. And, looking back over past El Niños, you could have expected that a more unsettled summer might be on the cards for the UK. Closer to home the North Atlantic is more than 2 degrees colder than normal. It seems quite likely that the unusually cold North Atlantic has strengthened and pushed our jet stream south, also contributing to the low pressure systems that have dominated our weather.

So could all this have been anticipated? Seasonal forecasts for this summer suggested that temperatures and rainfall would be near normal. However, as the season progressed all the leading models around the world failed to capture the signal for unsettled weather over the UK. We all know that forecasting months and seasons ahead is still in its infancy and much more research needs to be done. On the other hand our day-to-day forecasts have been really successful in allowing us to warn of bad weather, highlighting yet again the benefits of our research that has delivered year-on-year and decade-by-decade improvements in forecasting skill. Our 5-day forecast is now as accurate as our 1-day forecast was when I started my career. This enables us to make so many decisions that keep us safe, protect our property, keep our infrastructure running and even when to go out and enjoy the sunshine!

All of this cannot happen without improvements to research and technology, and this week the first phase of our new supercomputer went live, five weeks ahead of schedule. This will enable us to provide even more accurate and relevant weather and climate forecasts to all of us, our government, emergency responders, and our many other customers at home and abroad.

The news that the BBC has decided that the Met Office won’t be their main weather provider when the current contract ends has raised the question of where will the new provider get their information from. It’s important to understand that no weather forecasting organization, whether it is a National Met Service like the Met Office or an independent company, can provide a service without a forecast, and that it is the leading meteorological agencies, like the Met Office, that build and deliver those forecasts. So whoever the BBC chooses to deliver their weather services in future, you can be sure that Met Office observations and forecasts will continue to be at the heart of them. We are committed to driving forward the skill and usefulness of our forecasts and ensuring that all of us benefit from the advances the Met Office makes in the coming years with our new supercomputer.

Highest temperatures and rainfall over the weekend

23 08 2015

Over the past 24 hours the weather has delivered a mixture of hot sunshine, thunderstorms, hail and heavy rain as we highlighted earlier in the week.

As expected, sunny skies and warm air being pushed northwards from the continent allowed temperatures to climb across central and eastern parts of the UK, reaching maximums in the high 20s and low 30s on Saturday with a humid feel:

Table showing Maximum temperatures for Saturday 22 August 2015

Location Maximum Temperature in C
Gravesend 30.9
Kew Gardens 30.9
Heathrow 30.7
St James’s Park 30.7
Northolt 30.6

These high temperatures set off two areas of thunderstorms, one over central southern England and another over the Midlands, moving into northern England. These storms caused localised surface water flooding and flooding of some properties in North Yorkshire as up to 30mm of rain fell in an hour. There were also impacts to the York-Leeds rail line.

Across the northwest of the UK it was fresher and mainly dry with some sunshine, while the areas in between were rather cloudy with some rain.

Overnight, the heavy, thundery downpours continued to move northwards, while heavy rain also spread into western parts of the UK. By this morning at 10am the rainfall totals for the 24 hours were as follows:

Table showing rainfall totals for the 24 hours up until 10am on Sunday 23 August 2015

Location Rainfall in mm
Bramham 62.6
Ryhill 54.6
Tredegar 40.6
Linton-on-Ouse 39.8
Scolton Country Park 36.8

During today, the heavy rain has continued to spread north and eastwards with a mixture of sunny spells and heavy showers following across the south. Ahead of this, temperatures across eastern England have again peaked in the mid to high 20s.

Table showing rainfall totals bwtween 10am and 4pm on Sunday 23 August 2015

Location Rainfall in mm
Hereford 20.8
Llanbrynmair 20.4
Sarn 17.8
Lake Vyrnwy 17.2
Porthmadog 17.2

The changeable weather will continue as we head into next week. Met Office National Severe Weather Warnings have been issued and everyone is encouraged to keep up to date with forecasts and warnings over the next few days and to make plans accordingly.

Rain or shine this weekend?

20 08 2015

You may have heard that this weekend could be cloudy and wet…or sunny and dry, that’s because as with other weekends this summer there has been some uncertainty in the forecast.

After a mixed week of some sunshine, rain and showers it looks like we’ll see more of the same over the weekend as a frontal system interacts with warm, humid air spreading northwards from the continent.

We are now fairly confident that on Saturday the UK will be split weather wise. There’ll be bright and breezy weather in the north west with a few showers. Meanwhile the south east will be warm and humid, perhaps hot with temperatures in the high 20s which could set off a few isolated thunderstorms. In between we expect to see a band of cloud and rain which could be heavy and persistent at times.

Overnight and into Sunday the wet weather is expected to become more widespread across England and Wales and move into Scotland with some heavy rain at times.


At the moment, central and western parts of the UK seem most likely to see the heaviest, most persistent rainfall as the frontal system pivots. However, this pivot position could change over the coming days, and this is critical because it will determine whether we need to issue weather warnings.

Once we have more certainty where the most persistent, heavy rain will be we will review whether a Met Office National Severe Weather Warning is required. Therefore, as ever, it is best to check the latest forecast if you have plans for the weekend.

Tony Berry, Visitor Experience Director at the National Trust said: “Despite the unsettled weather this weekend, there’s still loads to do at National Trust places across the country. From windswept coastal paths and woodlands to hundreds of historic houses and gardens, there’s always something to explore come rain or shine. We’ve got a whole host of activities to wear the kids out too, with everything from pirate adventures and fossil hunts (just remember to pack the waterproofs and wellies) to storytelling and wild art. And throughout August we’ll be bringing the coast to a whole host of cities across the UK in the form of a giant shell – Shellsphere – where passers-by will have the opportunity to see, smell, hear and taste the sea.”

Next week, we’ll continue to see a combination of drier, sunny days with cloudier spells and some rain or showers at times but it will be warmer than recently.

Wet and dull July

31 07 2015

UPDATE: The figures below have now been updated to include data from the 1-31 July 2015.

July 2015 was cool, dull and wet across the UK according to Met Office statistics for 1-31 July.

The month began with a record-breaking heatwave, with hot, humid air moving in from the continent.  36.7 °C was recorded at Heathrow 1 July, the highest recorded temperature in the UK since August 2003.

However the rest of the month has been characterized by cooler and often more unsettled conditions, particularly in the north, as a result of a westerly Atlantic air flow.  Rainfall has been above average in most areas, particularly across parts of East Anglia, central and eastern Scotland.

MeantempJuly2015 RainfallJuly2015

minimum temperature mean temperature sunshine duration precipitation
Jul 1 – 31 2015 Act (°C)   Diff from avg (°C)   Act (°C) Diff from avg (°C) Act (hrs) % of avg Act (mm) % of avg
UK 10.3 -0.6 14.4 -0.7 164.8 96 109.5 140
England 11.2 -0.4 15.8 -0.5 191.9 99   82.3 131
Wales 10.8 -0.3 14.4 -0.8 175.1 98 112.4 121
Scotland 8.7 -0.9 12.2 -1.0 125.3 89 152.4 153
N Ireland 9.6 -1.1 13.3 -1.3 117.4 84 116.8 144

The south-east has seen some drier and more settled weather with temperatures near average, although there has also been some changeable weather here with over 20mm of rain falling on the 24 July and some cooler temperatures and strong winds on 26 and 27 July.

Elsewhere temperatures have been below average, particularly in the west and north, and it has been a rather dull month with sunshine totals being below average across much of the country.

Data from the Met Office’s UK digitised records dating back to 1910. You can explore our climate data on our website.

A summer forecasting challenge for Friday

22 07 2015

Forecasting rainfall for the UK during the summer has always posed a more difficult challenge than other times of year – and the weather for this Friday is a perfect example.

The various computer models the Met Office uses to forecast the weather differ on how a low pressure system forming to the west of the UK will behave.

We know that it will bring some wind and rain to the southern half of the UK, but there is no consensus on exactly which track it will take across the country and precisely when it will arrive.

Below you can see the area most likely to see some persistent rain during Friday and into Saturday. There is a 30% chance that rainfall could extend further north than this. The system is likely to bring up to 15-25 mm of rain and winds of up to 30 mph, mainly in exposed areas.

Forecast uncertainties 24-25-July

Currently there are no plans to issue a weather warning for this event, but clearly it has the potential to affect people’s plans for Friday now summer holidays are in full swing.  You can hear more about Friday’s forecast in the video below.

We’ll be keeping a close eye on the situation as it develops to ensure everyone has the clearest picture of what’s likely for Friday, so it’s worth staying up to date with the forecast over the next couple of days.

The current situation is a good example of why summer is tricky because at this time of year the details are vitally important.

Will the showers be inland or at the coast, when will low cloud clear to let warm sunshine through? In winter this might not be so important, but in summer when many are outside making the most of all the UK has to offer it can make a huge difference to your day.

Familiar features of our landscape such as hills, valleys or the sea can cause subtle variations in heat and moisture and therefore dominate the local weather outcome.  This can result in big differences in the weather in quite small areas, it can be sunny on the beach but raining inland or a village fair could be rained off while the next village down the road is dry.

At this time of year it’s always a good idea to keep a close eye on the forecast as the situation can change from day to day.

We’re always harnessing new science and technology to make forecasting ever more accurate and summer forecasting is a major focus for future gains.

Early July sees big rainfall contrasts

20 07 2015

After a hot and humid start to the month, when record daily maximum temperatures were recorded at several stations across the country on 1 July, it has been a fairly average month so far for the UK as a whole. However, on a regional scale there are some contrasts.

Using figures up to 15 July, mean temperatures have been close to or above average, with counties in eastern and southeastern England highest relative to average.

Meanwhile, for rainfall there are more notable variations, with eastern parts of England having received around or less than half the amount of rainfall that would be expected by mid-month. For example, Surrey and Sussex have both recorded less than 20% of the month’s average rainfall with 7.8mm and 9.9mm respectively. By the 15th of the month you would normally expect around 48% of the whole-month average.

This is in comparison with parts of Eastern Scotland where some places have already recorded more rainfall than the whole-July average. Aberdeenshire and Kincardineshire have already seen rainfall in excess of July’s average at 79mm and 106.6mm.

After the hot, sunny start to the month there have been periods of unsettled weather, with weather systems arriving from the Atlantic bringing rain or showers at times. This has been interspersed with drier, sunny spells.

With west or southwesterly winds dominating, there have been some rather cloudy days in the south, leading to mild nights.

The table below shows figures for the 1-15 July. You would normally expect about 48% of the full-month average for sunshine and rainfall at this point in the month.

Mean temperature Sunshine duration Rainfall
1-15 July
Act (°C) Diff from avg (°C) Act (hrs) % of avg Act (mm) % of avg
UK 15.5 0.4 88.0 51 46.9 60
England 17.0 0.7 103.7 54 30.5 49
Wales 15.4 0.2 89.2 50 56.4 61
Scotland 13.3 0.0 66.8 47 71.9 72
N Ireland 14.2 -0.4 57.7 41 45.9 57


Annual State of the Climate Report for 2014 published

16 07 2015

A report which looks at all the climate variables that can be measured for 2014 has been released today.

The annual ‘State of the Climate’ report has been published by the American Meteorological Society, presenting summaries for all so-called Essential Climate Variables (ECVs).

These include various types of greenhouse gases, temperatures throughout the atmosphere, ocean, and land, water cycle variables, ocean variables such as sea level and salinity, sea ice extent, permafrost temperatures and others. The majority of these reflect a planet that is continuing to warm.

The exceptional warmth of 2014 occurred against a backdrop of neutral to marginal El Niño conditions. Europe was especially warm and all land regions apart from North America showed above average frequency of warm extremes.

Annual average anomalies (difference to normal) for 2014 for surface temperature from the Met Office’s global temperature dataset, HadCRUT4 relative to a 1981-2010 climatology period.

Annual average anomalies (difference to normal) for 2014 for surface temperature from the Met Office’s global temperature dataset, HadCRUT4 relative to a 1981-2010 climatology period.

Over oceans, global sea surface temperatures and ocean heat content were also observed to be exceptionally warm and sea level exceptionally high.

The significant warmth is reflected strongly in regions of snow and ice. Arctic sea ice was well below average but above the exceptional lows seen in 2007, 2011 and 2012. Glacier volume is declining year on year – preliminary results for 2014 make it the 31st consecutive year of decline.

Long-lived greenhouse gases continued to increase, primarily owing to rising carbon dioxide (CO2) concentrations, in addition to methane (CH4), nitrous oxide (N2O) and other minor trace gases.

The Met Office’s Kate Willett, a lead chapter editor on the new report, said: “The comprehensive view of the different variables in the report enables a better understanding of the interconnectedness of our climate system.”

‘State of the Climate in 2014’ is the 25th consecutive instalment of the report, which is lead by scientists from NOAA’s National Centers for Environmental Information, along with 413 scientists from 58 countries.

Met Office scientist Kate Willett leads the Global Climate chapter and several other Met Office scientists contribute, using Met Office Hadley Centre climate data. All reports are freely available online.


Get every new post delivered to your Inbox.

Join 7,502 other followers

%d bloggers like this: