Heatwave Summers: There’s more than 1976 & 1995

2018 has been a remarkable summer. On the back of the warmest May on record (since 1910) for the UK, we saw the 3rd warmest June (featuring the 2nd warmest daytime maxima) which was also the 5th sunniest and 9th driest (3rd driest for England). The first half of this summer has been the driest on record for the UK. Temperatures have remained consistently very warm, with localised regions seeing prolonged and sometimes record-breaking dry spells. Were it not for a wet spring, we might have more concerns than we already do about water supplies (with only United Utilities so far issuing a hosepipe ban). 2018 has yet to see a very hot spell, though that may change in the coming few weeks – climatologically the warmest time of the year (for example, the UK’s record temperature of 38.5°C was set on August 10th 2003).

But will this heatwave be remembered?

I pose this question because the manner in which this summer has been reported would seem to suggest we’ve only ever had one heatwave in the UK: 1976. At a push, maybe 1995 too. But the truth is, of course, far from that.

Even just last year featured a memorable heatwave. June 2017 saw 5 consecutive days of temperatures exceeding 30°C somewhere in the UK, with a peak of 34.5°C on June 21 marking the highest temperature recorded in June since…yes, you guessed it…1976.

Until this year, the driest first half of a summer was 2013, which also featured a 19-day streak of temperatures exceeding 28°C somewhere in the country during July (which was the 3rd warmest and 3rd sunniest). Yet, aside from the astute meteorological observer, no-one I speak to seems to remember it happening – something I find astonishing because of the contrast after the 2007-2012 spell of very wet summers!

Other remarkable summers have occurred in recent times. July 2006 is the warmest month on record for the UK, and set the warmest July maximum temperature record (later beaten in 2015). 2003 saw a severe heatwave across Europe which resulted in setting the UK’s all-time maximum temperature record of 38.5°C on August 10th, a month which went on to become the UK’s 5th warmest August. August 1997 was the 2nd warmest on record for the UK, only slightly behind 1995. And before 2006, July 1983 was the warmest month on record for the UK.

In terms of mean temperatures for the UK, 1976 is only 3rd (tied with 2003) with 2006 taking pole position. However, 1976 and 1995 are the top 2 in terms of maximum temperatures, followed by 2006 and 2003. Rainfall wise, the driest summers are 1995 and 1976, followed by 1983.

I can’t deny that the string of hot temperatures, and the truly “flaming” June of 1976, were incredible. The water shortages caused by the preceding hot summer of 1975 (even more forgotten, with a hotter August than 1976!) and dry 1975-6 winter, were historic. But other historic heatwaves have happened since.

So, will people look back and remember the dry and hot summer of 2018? Only time will tell, but the evidence of “forgotten” recent heatwaves seems to suggest it won’t get the recognition it deserves.

Perhaps it’s a generational thing.

Perhaps people don’t spend as much time outside anymore – as someone who’s outside a lot (aside from being a meteorologist) I have always noticed the warmer spells even in a poor summer.

Perhaps, because the summers preceding 1976 were so much poorer (the 1960s lacked anything that could be called a ‘heatwave’ summer), we’ve just become accustomed to warmer summers and there’s less of a ‘wow’ factor when a heatwave does come along.

Despite all of that, I’d like to think people will remember this summer due to England’s performance in the World Cup and how well it timed with the peak (so far) of the heatwave. If only we’d won it, then it would really be a magnificent combination!

I’ll close with this thought: has anyone ever said “Summer weather was so much worse when I was a child!”.

Thoughts upon finishing the MMet

Yesterday (May 11), at about 10:50am, I completed my Master’s Degree in Meteorology and Climate (MMet) at the University of Reading.

The exam – Oceanography (perhaps not the most typical way to end a meteorology degree, but I guess it highlights the diversity of the subject).

The way I finished it? Ending a question on the thermohaline circulation with, “And with that, I’ve finished my degree!”.

It’s a surreal feeling when it’s a moment that’s been coming for the last four years. It’s been a long slog. Like everyone who studies meteorology at university, I can confirm it’s a tough subject – full of concepts and equations that (for me at least!) have required a caffeine addiction (thanks, Taylors of Harrogate) and a lot of head scratching to understand to the required level. From linear algebra and differential equations, to fluid dynamics in the laboratory, boundary layer fieldwork… and hours of programming. The Reading degree is thorough, to say the least. But it was everything I could have wanted, and more. I finally have the understanding of the atmosphere (and, apparently, the oceans as well!) which I so craved when I first became interested in the clouds above my head.

What’s worth more, though, is the understanding of the sheer scale of the atmospheric science discipline, and just how much I don’t know. The most challenging class I took was Advanced Synoptic at the University of Oklahoma (taught by Howie Bluestein, all-round meteorology legend and someone who can plaster the whiteboard with the semi-geostrophic equations and make the whole thing less daunting than it should be!). I’d probably show the notes I made in this class to anyone who thinks that meteorology is just about standing in front of a weather map saying it might rain tomorrow. Here’s a brief look at them:

Deciding to study the MMet degree at Reading was the best decision I ever made, and it’s opened up a world of opportunities for me – both here and in Oklahoma, where I spent my third year. I’ll be studying for a PhD in Meteorology from September, sharing my time between Reading and Oklahoma yet again (which I’m super excited about).

Thank you to all the staff at Reading and OU for making it all worth it, and for sharing your knowledge in a consistently entertaining and passionate way. Thank you to all my fellow students and friends, who sufferred and celebrated through the degree with me. And, thanks to everyone on #WxTwitter – I’ve learnt a great deal from all of you!

I couldn’t recommend the MMet strongly enough to anyone with an interest in the atmosphere. You won’t regret it!

Reading Half Cancellation: Do people believe forecasts?

This year’s Reading Half Marathon was cancelled at ~6:40 AM on the day of the race (Sunday March 18) due to substantial snow in Reading and the surrounding area (indeed, across most of England…). The cancellation of the event only ~4 hours before runners would be taking to the course was far from ideal, with many having travelled from afar and stayed the night in Reading. As expected, there was much consternation on Twitter and Facebook, with runners venting their frustration at the last-minute cancellation. As both a meteorologist and a runner, this clash of my two favourite things was a bizarre experience.

The question is – was this last-minute chaos avoidable?

The answer, in my opinion, is a firm YES. And I believe the problem lies with the trusting of forecasts.

On March 13 (5 day lead time!), it became very clear from forecast models that the “Beast from the East” would be returning in time for the race. Cold temperatures were certain, but the extent and intensity of snow was more difficult to predict. I tweeted the Reading Half, enquiring under what circumstances the race would be held off:

I received no reply. As I had seen the Bath Half cancelled with the first “Beast” event earlier in the year, I was very aware that the same fate could befall the Reading race.

By Friday March 16, the Met Office had issued yellow warnings for snow in Reading with a more severe amber warning nearby. The forecasts for Reading (models such as the GFS, ARPEGE, etc.) indicated 3-5 cm of lying snow on Sunday morning. With the model consistency, the severity of the alerts from the Met Office and the huge distances people travel for the Reading Half, I was convinced enough at this point that the race should be cancelled:

Still, the race organisers made no mention of snow and just kept mentioning cold weather. They were determined to ‘plough on’ (pun intended). The announcements were mainly that they were “gritting the route” – which is all fair enough, but hardly going to work very well with significant snowfall, and not going to help those travelling from afar.

Come Saturday, the Met Office forecasts had become worse for Reading, with heavy snow indicated all night. Forecast models still suggested 3-5 cm lying snow on Sunday morning across the south. Runners began to feel less at ease with the idea of it going ahead, and those travelling far wanted clarity.

By Saturday evening, with heavy snow already falling, the organisers cancelled the kids’ fun run, and left Half runners with the statement that a “final confirmation could not yet be made”. More bizarrely, they stated that “if conditions deteriorate further” then they would reconsider.

Prof. Mat Owens from the Reading Met department was just as confused as me, and expressed his feelings toward the race in a great tweet:

 

The forecast was for exactly that overnight deterioration to happen, and it was still the same message that had been said for days.

metoffice

Met Office forecast from 6 PM on Saturday indicating high likelihood of HEAVY SNOW.

I went to bed knowing the Half would be cancelled, yet having to “pretend” as though it were on…just in case it was…somehow. I woke up at 6:15 AM to the expected 3-6 cm of snow, and had to wait until 6:40 AM to find out it was indeed cancelled.

Now, before criticising too much, I want to say I love the Reading Half. I’ve run it twice, and both races being up there with the best experiences in my life. I’m aware it’s a tremendously big and important race.

However, why did it take until the snow was there, lying on the ground, covering the start line, the route and the finish line, with the M4 and M5 paralysed, for the organisers to believe the forecast? The situation that unfolded on Sunday morning was exactly as predicted. There must have been a moment on Sunday where the organisers said, “Oh…the forecasts were correct.”

The fact is, we can now forecast so accurately that a 1 day forecast is pretty much a certainty, unless it’s for a shower in a given location (which we might never be able to accurately predict). The reason we have made such advancements in forecasting power is precisely to avoid situations like this. It’s one of the greatest achievements of the human race. It’s also perhaps the most under-recognised.

What INFURIATES me, is that the announcement on the day claimed that conditions had deteriorated “more than forecasted”. That is, when it comes down to it, a lie. Either that, or whoever was providing the forecasts was not giving the best available forecast. They claimed to have been in contact with the Met Office…well, the Met Office forecasts I was looking at had expected exactly what happened.

 

Capture

The official race cancellation announcement stating that conditions “deteriorated more than forecasted overnight”.

In my opinion, the announcement was to try and make forecasters a scapegoat for poor event management, with too much concern for a false-alarm scenario: “what if we cancel it and then it doesn’t snow?”. I was lucky to have not been so badly affected by this as I live only 2-3 miles from the start line – for those who travelled, I feel deep sympathy.

I sincerely hope Reading Half have learnt their meteorological lesson. And I hope people begin to understand that, whilst of course sometimes the forecast goes wrong, we can now trust it in times like these – and that’s thanks to the pioneering work of many meteorologists, data assimilation scientists and computer programmers over the last few decades.

It really is quite amazing.

But if anyone knows what reasons they had to fully believe the race could safely go ahead until 6:40 AM on Sunday, then please let me know – I’m all ears.

So…why the stratosphere?

On February 23rd, I accepted an offer of a SCENARIO-funded PhD studentship in the Department of Meteorology at the University of Reading for the project “How can the stratosphere help us predict the weather several weeks ahead?“. The project is supervised by Andrew Charlton-Perez and Steve Woolnough at Reading and Jason Furtado at the University of Oklahoma – giving the exciting opportunity to spend some time working in the School of Meteorology at the National Weather Center and attend conferences in the USA.

It’s a big thing taking on a PhD and I felt it made sense I elaborate somewhat on why I’m interested in the stratosphere. I’ve been talking about the stratosphere a lot recently thanks to the first major Sudden Stratospheric Warming (SSW) in 5 years. I found myself presenting about the SSW in the Department’s weekly ‘Weather and Climate Discussion‘ in the presence of several Year 10 work experience students – hopefully attempting to inspire future stratosphere researchers as I myself embark on that journey! The timing of my PhD offer couldn’t have been better – what’s better than having an interview for a stratosphere-related PhD whilst there’s a big fat ridge sat over the Pole at 10 hPa?

Boundary Layer meteorologists have it easy explaining their interest: “it’s where we live!”. Tornado researchers simply find awe in the atmosphere’s most destructive phenomenon that you can go out and watch. But the stratosphere? It’s not even the ‘sphere’ where weather in the traditional sense occurs! So how did I get ‘into’ it?

January 2009 saw one of the strongest SSWs on record – a wave-2 vortex split event that reversed the 10 hPa 60°N zonal mean zonal wind from record-strong westerly to record-strong easterly. The Met Office announced the SSW and explained how this meant we were going to see cold conditions with a risk of snow. As a 13 year-old I hadn’t seen much in the way of snow (yet…) so this was very exciting! I was fascinated by this phenomenon and it immediately made me realise the atmosphere was far more complex and beautiful than I’d first thought (and I was already in love with it).

The Met Office news release was accompanied with this diagram:

met office ssw

I remember being captivated by this and had a thirst for a better understanding. I began asking questions: How does this happen? How do the stratosphere and troposphere interact? How does this lead to cold outbreaks in the UK? Why does this give increased predictability?

As time went on, I continued to find the stratosphere fascinating – the almost intangible nature of its dynamics – vertically propagating planetary waves, the Polar Vortex, the Polar Night Jet Stream, the Brewer-Dobson circulation…perhaps it was something to do with this being a less well-understood subject, and certainly one so complex it wasn’t often in the public eye. I had always been fascinated by the large-scale motions of the atmosphere – and it seemed in the stratosphere, I’d found the largest scale of all.

In the first year of my undergraduate Meteorology degree I attended an RMetS meeting entitled “Stratosphere-troposphere coupling in the Earth System: where next?“. Much of it went way over my head, but it didn’t put me off and made me want to know more! In second year, I gave a presentation on the unique 2015-16 Polar Vortex, whilst in third year I took a ‘Weather Briefings’ class with Steven Cavallo and always found myself talking about the Polar Vortex! At any opportunity, I’d talk about the stratosphere.

And with all of the meteorology sub-disciplines, most of which interest me on some level, the stratosphere was the one that stuck. I couldn’t be more happy to be researching it further, and helping to improve subseasonal forecasting. It’s a dream come true – especially since I’ll be able to return to Oklahoma, too!

I summed up my interest to the work experience students as:

“Isn’t it incredible that something so entirely abstract that happens 50 km above your head can directly influence the temperature of the wind blowing in your face?”

Winter 2013-14: When the Rain was Tropical

This morning, I watched as my aneroid barometer here in Harrogate, North Yorkshire slowly crawled upwards towards 1030 hPa. It’s a far cry from the forecast surface pressure in the next few weeks across the USA, but it’s also a far cry from what was happening on this day 4 years ago.

At least in Harrogate, 18 December 2013 marked the start of the infamously cyclonic winter of 2013-14. I took “daily” barometer observations throughout that winter. (Rather unscientifically, I don’t actually know what time each day I took these readings and it definitely wasn’t consistent – but it still serves as one record of the extraordinary winter.)

DJF2013-14

The transition on the 18th from a strong anticyclonic regime to the cyclonic “hell” that followed is clear, and I’ve shown that with 2 different averages (dashed lines). The period during February also pushed my barometer to its limits…the scale runs to 965 hPa, which is the minimum value I’d noted down during the winter (Feb 8th).

I distinctly remember the onset of the winter reminding me of the wet summer of 2012, as both came on the back of a dry spell (though 2012 was much more significant in that regard) [and believe it or not, I stood beside Thruscross Reservoir in early December 2013 and remarked of its low water levels that “if we don’t have significant rain soon, we’ve got a problem”…we ended up with a very different problem!]. The swing from extreme to extreme is a signature of how both events were driven by stationary amplified patterns in the jet stream – both before and afterwards – something which has been a subject of recent research in the context of climate change.

Based on analysis from a Met Office report and subsequent journal articles, an enhancement of convection in the equatorial western Pacific (plus a few other things en-route) played a strong role in driving the wet winter of 2013-14 in the United Kingdom. Isn’t it just fascinating to think of torrential tropical downpours in Indonesia – an entirely different kind of rain – driving wet day after wet day in the UK? I think this serves as a reminder to always enjoy the weather – there’s always some fantastic dynamics behind it, even if it is just another rainy day.

I co-authored a summary report of the winter whilst studying Synoptic Meteorology Laboratory at the University of Oklahoma last year, which if you’re interested is available here: Winter 2013-14 Summary. 

 

 

 

A Storm of Ex-Hurricane Communication

MODIS_20171016.jpg

MODIS imagery of Ophelia at landfall on Monday October 16, 2017.

It can’t have escaped the attention of many members of the general public that a storm by the name of Ophelia smashed into Ireland on Monday killing three. Met Eireann issued a RED warning 48 hours in advance of Ophelia’s arrival, which is unprecedented forewarning.

However, this post is not about the drool-worthy atmospheric dynamics that drove the storm nor its predictability, or its impact (or the bizarre yet stunning effect of advecting Iberian wildfire smoke and Saharan dust over the UK, resulting in orange skies).

I’m talking about communicating the threat.

Now, communicating weather isn’t easy. Meteorologists have to work out what they know first, then work out what the public need to know, what they understand, and then how this might be interpreted. This is then complicated nowadays by the world of social media, where meteorologists may tweet technical information which might get mis-represented by those less in the know.

Ophelia really brought storm communication to the forefront of my mind.

The term used by the NOAA National Hurricane Center to describe a storm of tropical origin that has undergone mid-latitude extratropical transition is ‘post-tropical’ (a term they picked up off the Canadian Hurricane Center, it should be said!). It’s a great phrase for meteorologists, I love it and advocated its use before NHC started using it operationally. Before I critique the communication any further, I should say I think NHC did a wonderful job with Ophelia, and I don’t think they could have done much better. I mean, they even had to change their graphics layouts because of Ophelia’s extreme north-eastern location!

My problem lies with the desire that BBC News, BBC Weather and to an extent, the Met Office, had with trying to emphasise that Ophelia wasn’t a hurricane, simply because it was no longer technically fitting that description. The phrases “ex-hurricane”, “tail-end”, “remnants” were used. The storm was “downgraded”. None of these phrases are suitable for communicating the severe threat, and some give the wrong impression entirely. Indeed, BBC News ran an article which said “The hurricane will be a storm when it arrives” which doesn’t really make any sense, other than perhaps suggesting it would be at Beaufort Force 10…storm force…which isn’t correct either.

There was even some egg-on-Twitter-faces when the Met Office tweeted that Ophelia was “now an ex-hurricane”. Simultaneously, NHC issued an advisory with the headline “OPHELIA STILL A HURRICANE”…which, given they’re the Atlantic’s official hurricane forecasting centre, means it was. The contradiction, in my eyes, is unacceptable and there were many tweets to the UKMO pointing this out.

Ophelia, with a likely sting jet, was capable of the same kind of damage as a landfalling tropical cyclone. It was in no way a ‘remnant’, and since it was still producing hurricane-force sustained winds, it was still Beaufort Force 12…i.e. a hurricane! I’m sure the people of Ireland will refer to it as ‘Hurricane Ophelia’. I don’t pretend to have the answers to this sort of situation, and certainly Ophelia was an unprecedented situation. But I think there should be consistency, and if a storm is severe enough, that shouldn’t be underplayed based on some sort of meteorological technicality. Do the public care about the difference between a symmetric warm-core cyclone versus an asymmetric warm-core cyclone when the impacts are similar?

Perhaps Post-Tropical Hurricane would work. Perhaps we should have some form of intensity scale for our named storms? Whatever happens, I think there can be improvement. These are the most severe weather events that these islands receive…why underplay them?

“How did you get into weather?”

Something often unique to meteorologists is our ability to pinpoint the moment in our lives when we were captivated by the weather.

I’ve been interested in weather since 2002, when I was 6 years old. My hometown of Harrogate, North Yorkshire is a few miles east of the Washburn Valley reservoirs (Lindley Wood, Swinsty, Fewston and Thruscross). When I was growing up, they were a place my family often visited on a weekend, and one day my Mum noticed that Thruscross Reservoir was to be featured in an episode of Wild Weather, a BBC series presented by Donal McIntyre about weather extremes. Given how much I loved the reservoirs, we tuned in to watch Donal get pummelled by water from Thruscross in order to demonstrate the sheer power of water in the context of flash-flooding.

I was hooked, and watched the rest of the series multiple times, discovering more and more about the atmosphere. I was particularly inspired by the global scale…jet streams guiding weather systems for thousands of miles, something which has stayed with me ever since. I always remember that this series was where I first learned of the oceanic ‘thermohaline conveyor’. The fact that weather and reservoirs combined to spike my interest is no coincidence, as I always wanted to see the reservoirs overflowing or at very low levels…so rainfall surplus or deficits had always been on my mind. Perhaps the only other thing aside from weather in which I’m known to have an excitable interest is dams!

That was the first aspect of my life which pushed me towards meteorology.

But the other aspect is that I grew up into a world of weather extremes, particularly in the UK but also on a global scale, thanks (in part) to climate change. I remember the headlines in the summer of 2003 as the UK and Europe baked in a record-breaking heatwave (the one and only time the UK has surpassed 100°F). 2004 was memorable for the Boscastle flash flood in August, but I also remember being captivated by the frequent (at the time, record-breaking) tropical cyclone landfalls on the US.

I spent the summer (and autumn) of 2005 tracking the Atlantic tropical cyclones, which turned out to be memorable for many record-breaking reasons. I remember having no Internet access on the day Katrina made landfall and being heart-broken I wasn’t able to follow what was clearly an unfolding disaster. I remember the moment the NHC issued the advisory showing Wilma as the most intense on record. I have the list of names for that season committed to memory. I just fell in love with it.

By this point I’d become known amongst friends as a weather obsessive, but still the inspiration from the meteorological world around me kept coming. In July 2006, Britain experienced its hottest month on record, and then in September a weak tornado struck Harrogate and nearby Leeds which was a tremendous experience that I reported to TORRO with observations from my sister, who at the time worked in the tallest building in Harrogate and watched the event unfold.

Then followed the 2007 wet summer in the UK (which lead to the partial failure of the Ulley Reservoir in South Yorkshire…very exciting!), the failed “BBQ summer” of 2009, the 2009-10 cold winter, the record-breaking cold of December 2010, the record-breaking wet summer of 2012…and so on. These extremes and others helped commit my interest and also spurred my interest in the jet stream, which will be the focus of my final year research project at the University of Reading.

I can’t imagine my life without an interest in the atmosphere; I often find it hard to think how one couldn’t be interested in trying to understand the chaos above our heads. With climate change a serious issue for everyone, it’s my hope that everyone will gain a little more understanding about the power and beauty of the skies.