I’ve seen this phrase uttered more than once over the past couple of days thanks to high temperatures and humidity. But ask anyone to define a hot day and you’ll get a different answer every time.
Growing up in the 1970s / 80s redtop newspapers would use the phrase once the mercury was nudging 80F (26.7C). But to ‘scorch’ you need sunshine, preferably at least 10 hours of it. Considering statistics from the Heathrow airport climate station in west London there have been 463 scorchers since 1959, the most recent happening on July 5th with 29.5C recorded and 13.9 hours of sunshine. There have now been 9 scorchers this year, already matching the number that were recorded in 2014 and only 3 short of last year.
But even with last month’s heatwave this year has some way to go, however, to match the amount measured in 1976 and 1995: 31 days!
Though there were no records broken August 2016 goes down as a mighty fine summer month, the warmest for 12 years. The mean of 19.5C was 1.3C warmer than average and only 0.1C cooler than 2004.
The month ended a three-year run of poor or so-so Augusts: in terms of mean temperature the month was the 10th warmest in a local series going back to 1797.
It was another very dry month: just 11.9mm fell, 24 per cent of average, the driest August since 2003 and the 12th driest in the local record.
The month only falls down in terms of impressiveness when sunshine hours are considered. Some 192 hours were recorded, the 59th sunniest since 1797 – 1995 had 80hrs more sun.
Air frosts: 0, Ground frosts: 0
So what has September got in store weatherwise? The models on the 1st suggest the month will start mixed, though any precipitation will be below average. Temperatures remaining on the warm side.
Beyond the grasp of the models my long range outlook method is again hampered by a very dry August. However, the data I do have suggests an average month at 100 per cent probability.
A wetter than average month looks most likely at 75% probability.
The rainfall probability makes me wonder whether we are in for a very unsettled second half of September, the Atlantic cranking into life with the remnants of tropical storms and hurricanes having an ever-increasing influence as the month progresses.
So to sum up: mean 15.3C (average), rainfall 162mm (300%), sunshine 140 hours (100%).
My August outlook for temperature was good. I predicted a mean of 19C (outcome: 19.5C). It was drier than I thought: 30.3mm (outcome: 11.9mm). Sunshine was poor: 239 hours (outcome: 192 hours).
1st: Cloudy start to 1pm. Rain started at 5pm through to 10pm. A brief interlude before more light to moderate rain through the night 4.30am, then drizzle
2nd: Damp, miserable start – the rain became light to moderate in the early afternoon before drying up – very high dew points through the day.
3rd: Bright and breezy with variable cloud.
4th: Bright start with variable cloud and sunny spells.
5th: Good sunny spells all day – perfect summer’s day, not too much humidity – though an isolated shower passed over at 8pm.
6th: Sunny, clear start. Lots of sunny spells during the day.
7th: Bright start though very breezy. Cloud decreased through the day to leave a gorgeous late afternoon and evening.
8th: Sunny, clear start with lots of fair weather cumulus throughout the day. Cloudier spells mid afternoon.
9th: Sunny with fair weather cumulus up until noon then cloudy afternoon.
10th: Sunny with fair weather cumulus, variable throughout the day. Breezy.
11th: Cloudy start with very brief light rain, barely enough to damp ground. Some sunny intervals later and bright and warm.
12th: Sunny start with a few clouds. Turned gin clear at 11am and stayed clear all day. Feeling hot.
13th: Bright start but turning cloudier. Sunny intervals PM.
14th: Cloudy start breaking to some long sunny spells. Feeling very warm in the sun.
15th: Bright start soon turned sunny with a clearance at 1pm.
16th: Bright start though a lot of haze around. Sunnier later though still hazy.
17th: Sunny with patchy cloud to start, this clearing late morning to leave a clear if rather hazy afternoon.
18th: Sunny if a bit hazy to start, this tending to decrease to leave warm sunshine.
19th: Cloudy with rain threatening. Low cloud at Stansted. Brief rain in afternoon then cloudy.
20th: Dull and overcast at 9am. Burst of heavy rain at 10.15am clearing to sunny spells at noon 30. Rain between 7pm and 8pm and 3am and 4am.
21st: Bright start. Sunny intervals till 3pm then sunny spells.
22nd: Bright after earlier rain at 0719 then sunny spells.
23rd: Clear and sunny start with a few cirrus clouds through the day. Hot.
24th: Sunny, gin clear start. Patchy cirrus through the day. Hot.
25th: Lots of altocumulus and sunny spells but felt sultry due to high dew points.
26th: Cloudy start but gradually decreased to leave clear pm.
27th: Overcast but bright start. Brightness through the day but hazy. Some heavy storms further north.
28th: Overcast until early afternoon, 5 minute shower at 2pm then sunny intervals..
29th: Bright start then sunny spells and cirro cumulus gradually clearing to leave a sunny evening and clear night.
30th: Clear and sunny start.
31st: Bright start though cloud filling in by 3pm, clearing again at 8.30pm
The past few days have offered a couple of perfect examples of how wind direction can have a massive effect on the resulting maximum temperature at this time of year.
Friday, August 12th and Monday, August 15th, were both very similar in that any morning cloud completely cleared by 11am. But while the wind blew from a SW’ly direction on Friday, nudging Wanstead up to a very warm 28.1C, by Monday the high pressure had drifted north, drawing in a cool NE’ly flow off the North Sea. The high temperature in Wanstead on Monday was nearly four degrees cooler at 24.4C.
Under these conditions temperatures will be warmer the further west you go, as the graphs below show.
There was plenty of interest in the weather last month even though the overall stats suggest July 2016 wasn’t that remarkable.
Most notable was temperature: the warmest minimum on record for this area (21.1C) was recorded during the early hours of the 20th – coming hours after the hottest day of the year: 33.5C – the 14th hottest day on record. The mean temperature of 19.5C was a degree warmer than average, the 18th warmest July since 1797.
Rainfall was very sparse. A total of 17.3mm fell during the month, that’s 40 per cent of average, the driest for six years and the 19th driest in the series going back to 1797.
After a very dull start to the month sunshine was always going to struggle: just under 172 hours were recorded – that’s 89 per cent of average and marginally down on last July.
Air frosts: 0, Ground frosts: 0
So what has August in store weatherwise? The models on the 1st suggest the month will start with a mixture of sunshine and showers. At the end of this week there are indications of a change to warm and later very warm weather.
Beyond the grasp of the models my long range outlook method is hampered this month because of the very dry July. However, the data I do have suggests a rather warm month at 50 per cent probability. The ‘worst case’ scenario suggests something average, a contrast to the past couple of Augusts which have been poor. Perhaps we can look forward to another reasonable summer month, defined by plenty of fine, at times hot, weather – though anyone looking for unending days of 30C and higher will be disappointed.
A dryer than average month (possibly very dry) looks most likely at 50% probability. A very sunny month looks most probable.
So to sum up: mean 19C (0.8C above average), rainfall 30.3mm (60%), sunshine 239 hours (123%).
My July outlook for temperature was good. I predicted a mean of 18.8C (outcome: 19.5C). Rainfall was very poor: 50mm (outcome: 17.3mm). Sunshine not badr: 171.9 hours (outcome: 190 hours).
1st: Cloudy with sunny intervals. Some sharp showers.
2nd: Bright start though breezy. Very heavy shower at 1740.
3rd: Sunny though with lots of cumulus.
4th: Sunny, gin clear start though cumulus rolled in at 1.30pm.
5th: Cloudy start with very brief, very light drizzle though with sunny breaks developing.
6th: Hazy mix of cirrus and cumulus gradually decreased to a clear sky by 1pm. More cumulus bubbled up later but still mostly sunny and low humidity.
7th: Sunny start with lots of cumulus, cirrus and stratus around. Sunny spells through the day.
8th: Cloudy and breezy start.
9th: Bright start with sunny spells but also lots of cloud. Amazing sunset with fronts coming in.
1oth: Cloudy start with light rain spreading in but only lasting for 40 minutes. Some sunshine in the afternoon though was breezy.
11th: Cloudy start with heavy showers early afternoon.
12th: Sunny start though with plenty of cloud which bubbled up and gave heavy showers from 11.30am. More showers in the afternoon – miserable.
13th: Bright and sunny to start that cloud gradually built before heavy showers hit at 2pm, these lighter over Aldersbrook.
14th: Sunny, bright start with sunny spells, tending to turn cloudier.
15th: Bright start but cloud piled in and breeze picked up.
16th: Sunny start with lots of cirro-cumulus. Cloud tended to build at times and a front passed over at 4pm. Warm evening and night.
17th: Bright start though with lots of heavy cumulus around. This tended to break up at intervals during the day, making it feel hot in the sun because of the high humidity.
18th: Sunny start with patchy cirrus and cumulus. This decreased as day wore on leaving a hot day. Felt almost airless with variable cloud.
19th: Sunny with decreasing cirrus to start to leave a gin clear day. Breeze picked up at noon meaning it wasn’t as warm as it could have been.
20th: Sunny but hazy start but with more of a breeze than yesterday. Cloud tended to fill in but then burnt off to leave another hot day.
21st: Sunny but cooler start than yesterday with lots of milky cumulus around.
22nd: Cloudy start after overnight rain. Sun breaking through at 12.30pm.
23rd: Cloudy start with spots of drizzle at 11am then slowy getting brighter with evening sunshine.
24th: Cloudy start with early showers breaking to sunny spells.
25th: Sunny start with variable amounts of cloud through the day. Feeling cooler.
26th: Sunny start though with cloud bubbling up through the morning. Overcast by 2pm.
27th: Cloudy and damp with light rain before and after obs time.
28th: Sunny periods with variable cumulus
29th: Cloudy start with brief rain showers in Chigwell. Sky broke to allow long sunny spells before it clouded over again. Rain shower at 9pm.
30th: Cloudy and overcast start. Long sunny spells into the afternoon.
31st: Sunny start though more cloud tending to bubble up in the afternoon.
Storm clouds gathering was a common sight in June 2016, but enough about the tumultuous political situation…
For anyone looking for summery weather there was little to cheer about. For sunshine the month was the dullest June in a record going back to 1797. Just 96 hrs were recorded – which is just over half what we can expect in an average June.
Most notable was the rainfall: just over 139mm fell which is 272 per cent of average, and the third wettest since 1797. Only 1903 and 1860 were wetter. The month also saw the record broken for highest daily rainfall in a 24-hour period. A multi-cell thunderstorm in the early hours of the 23rd saw 60.8mm fall, most of it in two hours, bringing flash floods to the surrounding area.
With the lack of sunshine and copious rainfall it is, perhaps, surprising that the mean temperature for the month finished just above average: 16.8C is 0.7C above the June average. The warmest day was the 10th with 25.3C recorded – only one other day saw the mercury exceed 25C – very unusual for this time of years.
Air frosts: 0, Ground frosts: 0
So what has July got in store weatherwise? The models on the 1st suggest more of the same weather that we have seen during the last third of June. Sunshine and showers with the occasional ridge possibly calming things down for a few hours.
Beyond the grasp of the models my long range outlook method suggests a rather warm month at 50 per cent – so given the cool start perhaps we can look forward to something summery in the final half to one third? Rainfall and sun looks inconclusive so I would guess average. Because of the high rainfall last month I think my long range method falls down.
A slightly wetter than average month looks most likely at 50% probability. Sunshine probably about average.
So to sum up: mean 18.8C (0.3C above average), rainfall 50mm, sunshine 190 hours.
My June outlook for temperature was good. I predicted a mean of 16.9C (outcome: 16.8C). Rainfall was very poor: 38mm (outcome: 139mm). Sunshine very poor: 178 hours (outcome: 96 hours).
1st: Cloudy and cool all day.
2nd: Cloudy and cold all day, brief brightness at 11am.
3rd: Cloudy and cool all day, limited brightness late morning. Cloudy overnight with limited breaks – air was very humid with warm front and visibility severely limited.
4th: Cloudy all day though cloud was lighter and air felt warmer because of the warm front that came in yesterday from Europe. Brief milky sunshine at 7pm.
5th: Cloudy up until 9.30am when the cloud began to thin. Sunny spells from 11am before a clearance at 1pm interspersed with occasional cloud.
6th: A gloriously sunny day all the way through. A lovely evening too.
7th: Sunny start but cloud rolled in at 1.30pm with thunder heard all around Wanstead. Some serious flash flooding in Croydon. Highest official total was over 40mm in Kenley. Just 1.7mm during the day but trough brought rain at 5am, about 3mm.
8th: Sunny start but felt very humid and oppressive. A thunderstorm skirted Wanstead at 1.40pm with thunder and much rain in Chigwell, not much in Wanstead. More thunder at 2.10pm. Rain came and went for rest of day until 7pm – very little upper air movement. Mostly cloudy overnight.
9th: Cloudy start but some sunny spells developing.
10th: Cloudy start but soon decreased with long sunny spells developing. Lower humidity so felt pleasant.
11th: Cloudy and humid start with very heavy rain at 3pm. This lasted for 45 minutes. More rain fell sporadically through the day, evening and overnight.
12th: Cloudy after moderate rain. Showers and longer bursts of rain returned before a brief clearance at 3pm. More showers piled in with a real corker to the north of Wanstead.
13th: Damp start soon led to light rain, turning persistant at 11am. Then outbreaks of rain throughout the day, evening and overnight.
14th: Light rain to start but this quickly gave way to heavy showers all day. Some brightness at 6pm then turning drier overnight. Gin clear dawn.
15th: Sunny start but with lots of convective cloud. Some drizzle but a heavy shower stayed to the east of Ilford.
16th: Bright start with sunny spells, more breeze than recent days
17th: Lots of cloud around though sunny spells arrived early afternoon. Then showers between 5 and 6pm.
18th: Cloudy with spots of drizzle. Feeling cold all day – a maximum of only 16.5C.
19th: Sunny start but cloud gradually increasing all afternoon. Rain by nightfall that fell intermittently for hours. Rain again at obs time.
20th: Rain to start that lasted, with variable intensity, through the morning. Sunny spells from mid afternoon.
21st: Sunny start with just a few cirrus and cumulus, this tending to increase through the morning to leave an overcast afternoon. Cloudy overnight – a few spots of drizzle on school run as frontal wave started to move across UK.
22nd: Cloudy start with warm sector drizzle. Showers developed at 11pm, much thunder and lightning and the rain turned really heavy through the early hours.
23rd: Cloudy and humid to 1pm. Showers at 3pm.
24th: Sunny with variable cloud. Feeling humid in the sunshine.
25th: Bright start with sunny intervals. Light shower at midday. Thunderstorms at 2pm, 4pm and 9.30pm.
26th: Sunny spells though significant cloud at times. Rain between 4 and 6pm.
27th: Mostly cloudy though with some brightness after noon. Warmest point was in the evening at 7pm.
28th: Bright though cloudy start. Some sunny intervals but rain late afternoon into the evening. Cool overnight.
29th: Cloudy and breezy, some rain in the air early afternoon and again in the early hours
30th: Cloudy with slight breeze. Some light rain in the early hours.
The past week has produced the highest 24-hour rainfall total recorded in Wanstead since at least 1960. The multi-cell thunderstorm on Wednesday night saw 60.8mm fall, most of it in two hours, bringing flash floods to the surrounding area. The spectacular lightning and thunder that accompanied it was almost a side show such was the intensity of the rainfall.
I was unfortunate enough to be riding home right in the middle of the event: the entire length of the Mile End Road bore a resemblance to a shallow river, the heavy rainfall bouncing back off the Tarmac high enough to create what felt like a powerful drench shower.
The legacy of the downpours caused chaos in the morning and evening rush-hours. Many commuters were stranded at London terminals including Waterloo station because of flooded tracks, possibly robbing many of the chance of voting in the EU referendum. It will never be known if this would have had a bearing on the final result.
Many people think of June as a warm, summery month. The term Flaming June is regarded in most peoples’ subconscious as a reference to past weather. That it is a actually the name of a painting is often missed. Looking back through our local history there has been many notable events of thunderstorms and prolonged rainfall. In 1903 a record-breaking 59-hour deluge left vast swaths of the borough inundated.
This weekend 200 years ago, during the Year Without a Summer, a powerful tornado, strong enough to carry away objects weighing 60lbs, tore through the Edgware Road area in west London. Luke Howard recorded the event in the Climate of London.
At two o’clock being a still sultry day a whirlwind passed over the nursery ground of Mr Henderson in the Edgware Road which lifted seven lights from the greenhouses and carried them to the height of the highest elm trees, each of the lights weighs 50 or 60lbs at least. At the same time two garden mats were carried to an immense height so that the eye could not distinguish them.
The following day “extremely heavy and prolonged rain from 9am (26th) to 9am on 27th gave 2.95 inches”. This total of over 52mm is notably high though not a record.
This weather was a continuation of what had been an awful May and June – cold with more than twice the average rainfall in June.
The weather then was not unlike what we have experienced this month. Indeed, a look at the weather throughout this year was similar as this graph shows.
Though the mean temperature at times bears a close resemblance this year is no comparison to 1816: The mean then was running at 6.2C, over 3 degrees colder than today.
Mean pressure was also lower being 992.1mb; the 2016 mean 9am pressure is 1010.6mb.
Perhaps not surprisingly this year’s rainfall actually trumps 200 years ago; the running total for rainfall here is 390.1mm, higher than the 309.6mm recorded in 1816.
The dreary summer and frequent thunderstorms of 1816 inspired Mary Shelley to write Frankenstein. A summer vacation in Switzerland led her to spend much of the time indoors. She, along with Lord Byron and John William Polidori entertained each other with a contest to write the scariest story of all. The unseasonal conditions, along with this dare, led to the creation of Shelley’s Frankenstein: The Modern Prometheus— as well as Polidori’s novella The Vampyre and Byron’s long-form poem, The Darkness.
It will be interesting to see if this June’s weather, along with momentous political changes here and in Europe, produce more fine fiction from the this and the next generation of writers.
The cold start to June may soon be a distant memory once summer proper gets going in east London. But rather than a succession of prolonged hot, dry spells it’s looking like the season overall will be broadly average – you will hear the old saying: ‘an English summer consists of three fine days and a thunderstorm’ more than once this year.
Looking at summers back to 1799 I’ve tried to find a pattern linked with a declining El Nino. And failed to find anything conclusive. With ENSO forecast to be approaching neutral by August I decided to discount it completely, instead relying on pattern matching of meteorological data from this area for March, April and May stretching back to 1799.
The mean for the spring season was 10C with 156.4mm of rain and 455 hours of sunshine.
If you take into account all years that were within +/- 10 per cent of these figures, for rainfall and then mean temperature, some 36 ‘best fit’ years emerged, far more than my previous two attempts to forecast summer. The years, ranging from 1805 through to 2007, saw all manner of summers – only one was a real corker, 1825, but most were fairly nondescript average affairs. As an average this summer could be expressed as: Mean: 16.7C (just above average) Rainfall: 166mm (exactly average) Sunshine: 546hrs (about average)
Or, expressed in probabilities, I concluded the following:
From the above you could deduce that the next three months will be slightly warmer than average, with average rainfall and sunshine.
Last year I tried to decipher, with fair success, when hot spells would occur. However, looking at the data of these 36 summers very warm, dry spells happened through the three months – it was impossible to find any exact pattern to when it would be warm and dry.
Instead I’ve broken down the summer into June, July and August probabilities.
Looking at June, considering this cool and cloudy start, I would guess that we can look forward to a few very warm, thundery spells – a repeat of the Spanish plumes of the past couple of years.
Considering the above data perhaps there is a greater than evens chance of some thundery activity – and the nature of thunderstorms mean you can get a deluge or stay relatively dry / average. Sunshine average.
On to July. After a ‘rather warm’ June I wonder if the ‘return of the westerlies’ will happen just in time to affect this month?
The above chart would suggest that July will be classically average overall. Fine, not too hot spells, with occasional depressions bringing cooler weather and showers.
On to August. This month has been a real disappointment the past couple of years. However, I think this year August may offer a bit more in the way of sunny weather.
Looking at the above probabilities there seems a fair chance of something average to rather warm overall. With rainfall below average and average sunshine I wonder if there will be two or three fine spells throughout August – perhaps more?
So, all-in-all, summer looks a mixed bag. How this summer will fair obviously only time will tell. One could argue that what I’m forecasting is just climatology which has a good chance of being correct should no external influences, such as a huge eruption on Mount Etna, have a bearing on the end result.
* Taking into account the fact that temperatures in London are up to 0.66C warmer than they were 100 years ago I have added 0.66C to mean temperatures before 1915.
** Obviously, in the event of a series of direct hits from thunderstorms, my rainfall estimate could be hopelessly short – a symptom of abundant solar energy at this time of year which creates a ‘noisy’ atmosphere compared with winter.
*** The 1981-2010 average mean for summer in this region is 17.6C, with 144.9mm of rain and 564 hours of sunshine
Before I’m accused of going all Daily Express the following is based on winter statistics for the London area and other variables rather than the latest expert hopecast.
Even before looking at the data in depth the chart below shows that a warmer than average summer is more likely after a mild winter. The winter just gone was the third mildest in a record going back to 1797.
There are some real corkers in that list, including 1995 when this area recorded the driest August on record. Other notable summers included 1990 – England in the semi-finals of the World Cup and another notably fine August: the then hottest UK temperature was set that year when a maximum of 37.1C was recorded at Cheltenham – a record that lasted until 2003. The year 1989 also stands out with a notably sunny summer.
So far, so good. But what about rainfall? Some 145mm of rain fell this winter – pretty much on the nose average for this region. Combining warm winters with similarly average rainfall gives the following list.
Though some years have disappeared there are still some decent summers, and notably sunny too. The year 1975 stands out as does the sunniest summer on record, 1911! Both were also very dry summers.
Altough the teleconnection with El Nino is tentative in our part of the world the winter seemed to follow the pattern of most positive ENSO episodes, so it is worth having a look to see where the data goes. The latest forecast by NOAA suggests:
A transition to ENSO-neutral is likely during late Northern Hemisphere spring or early summer 2016, with a possible transition to La Niña conditions during the fall.*
If the forecast goes to plan the second ‘rainfall list’ would narrow further:
Viewed by graph reveals that ENSO values of all the years decreased over the course of the year. Series 1 is 1998, series 2 is 1983 etc.
In conclusion, the results would suggest that there is a 66% chance of a decent summer with below average rainfall and above average sunshine. In terms of details June 1st is still a very long off in meteorological terms – so whether it includes any heatwaves that would put it my premier league of hot spells is anyone’s guess at this range.
If it’s anything like 1959, 1975, 1983 or 1998, however, I think most folk will be happy.
*The above contradicts some forecasts which suggest a continuation of the general pattern that persisted during the winter: warm SSTs in the Atlantic / warm water south of the Grand Banks were largely responsible for the cyclonic westerly type of weather that caused the mild weather. In summer this would cause changeable weather rather than long spells of settled weather.
Summer 2015 has got quite a bad press over the past couple of weeks but it hasn’t really been that bad overall in this area. And, as ever with the weather, it wasn’t without interest.
Two extreme records were broken: The maximum on the 1st of July of 36.1C and the minimum on the 30th of July of 6.9C. There were also a couple of cracking thunderstorms.
Mean temperature for the three months was the lowest since 2012, the same year that saw more rain than this summer’s 167.7mm. Both 2012 and 2011 were a fair bit wetter than this summer and this season’s rainfall wasn’t a patch on some of the washout summers of my youth – both 1985 and 1987 were at least 150% wetter than summer 2015.
More notable was the lack of sunshine – it was the dullest summer since 2002.
Looking beyond Wanstead the perceived poor summer elsewhere was largely caused by cooler than normal sea temperatures west of Ireland, together with warmer water around the Azores. Simon Keeling explains this well here.
Three months ago I predicted that summer would be broadly average temperature-wise with average to slightly below average rainfall and average sunshine. So how did the forecast do?
In terms of temperature my predicted figure of 17.4C was 0.5C lower than the result. My rainfall prediction was only 76% of what actually fell and I over-estimated sunshine by 16%.
Despite some of the dire reviews of summer elsewhere in the UK there were some fine spells