Are We In For A Hot Summer?

[SP1986]

I think I recall someone quite rightly suggesting that the summers of 2003 and 2006 were unusual events, possibly one in 15-20 year events and they are unlikely to happen for another 10 years at least. If they did happen then that would support an acceleration in extreme events, but I seriously doubt this. Perhaps this year we will see an 'average UK summer'? Not my opinion but average is something we havent seen for a while.

[SNOWPLOUGH]

One thing I feel could happen this summer is that the temperature won't reach 30C anywhere in the UK or Ireland,when was the last time this happened?

I think this summer will be cool,perhaps cold,but very sunny and possibly dry at the same time,high-pressure dominated.This is just a pure guess.

Also with such a long solar minimum maybe a cold winter to follow.

SP

Edited April 9, 2009 by SNOWPLOUGH

[GRHinPorts]

Theres really little link between what the weather does in Spring and what the following summer turns out like. Its just the same as trying to predict what winter will be like based on what Autumn does. Theres no link at all.

Take 2002 and 2003 for example. Both years saw very warm springs with almost identical means, the synoptics were even quite similar, yet the summers were vastly different.

2002:

March: 7.6C

April: 9.3C

May: 11.8C

Summer: 15.8C

2003:

March: 7.5C

April: 9.6C

May: 12.1C

Summer: 17.3C

Whether spring is mild or cold, wet or dry, blocked or unblocked, summer will do what it does and theres no proven link.

I distinctly remember watching a Christmas special of Gardeners World at the end of 2002 in which Alan Titchmarsh said he hoped we all enjoyed the spring of that year since it was one of the best he could ever remember.

And then lo and behold 2003 delivered a spring every bit as good.

**********************

With regard to this years summer I am a great believer in the British weather averaging itself out in the end.

Take 2007 as an example...I was never very confident of summer once we got to the end of April with a +8 differential in the CET (January +3, Feb & March +1 each, and April +3)...that was ridiculous warmth and I was pretty certain the summer would see a balancing act which it did.

Also in 1976, the year of the great drought, the years rainfall still came in pretty close to average when it tanked down the whole of Autumn.

This year we have seen a pretty cold start to the CET. Going on the 1971-00 averages we are just 0.5 of a degree down to end of March but as I have only lived in the UK since 1997 I have also looked at the average from then to now (* )and on that we are a huge -3 degrees down to the end of March. So I would expect a correction of some sorts in the remaining 9 months especially as 2008 was the 2nd coldest in the run since 1997.

One of the other things I have done is look at the differential for each month comparing the 1971-00 averages with the 1997-2008 ones. In the former series the CET averages out over each year at 9.75...whilst in the latter its 10.42...an annual differential of .67 degrees over the whole year. Now statistically you might expect that differential to be the same across all 12 months but this is far from the case. Some months (May, September and especially February) have been significantly wamer than the average differential (February almost twice as much even factoring in the cold 2009) whilst other months are falling short of the 0.67 differential. These include August and October slightly, July (amazingly when you consider the record heat of 2006) and December (which for all the complaints about warmer modern winters is the only month which has actually been colder (just at -0.03) over the past 12 years then it was between 1971-2000.

So based purely on a belief that things will average themselves out my prediction is that the best of the summer will come in in July and August (perhaps after a disappointing June). I also think the chances of a record mild December cannot be that far off which when it comes will no doubt produce much wailing and gnashing of teeth on here

* I chose to look at the CET averages for the years that I have actually witnessed because it helps to understand what I would call are anomolous months. For example the June of 1999 (at least here in the South) was a significantly nicer month (dry and sunny pretty much throughout - although with cool nights) than August of 2004 (pretty much wet and mild throughout) despite the latter month being over 3.5 degrees warmer.

Edited April 9, 2009 by GRHinPorts

[Bottesford]

Haha, that is probably the only downpoint of summer, it is great during the day if you're like me and love soaring temps into the 30s, but night time temps in the low-mid 20s are very unpleasant, and even with the window open it is very hard to sleep

I only really like the soaring temps in order to create the warm evenings! 27c is the absolute most I need - and 25c is better really. But I like it 30c+ as that means it takes longer to cool off in the evenings. 23c is a great temp but if it only takes place whilst I'm in a stuffy office with it down to 17c or lower by the time I can relax then it's no use!

Best for me is 25c max 18c min and reasonably humid as it's neither too hot nor too cold for outdoor activities.

I don't have trouble sleeping in heat these days - shut the sun out during the day, get all the windows open at night and loose the huge duvet/pjs. The gentle warm and nice smelling breeze will cool you as you lie still - perhaps putting an ice pack under you're pillow if you're still warm. Invest in a fan if still cold!

Surely no more difficult to deal with than getting up to the freezing cold & dark for work on a January morning having been woken up an hour before as the heating cranks & creaks starting up. Not to mention the bone dry throat if it happens to be a milder morning but the heating is still burning away as if it were still -4 out there!

[Thundery wintry showers]

I find hot nights a problem because if I open the window lots of creepy crawlies (esp. mosquitoes) come in just as I go to bed, and being partially sighted it can take hours to hunt down the things, so I don't go to bed until a couple of hours later than I intended. If I leave them alone I get mosquitoes right in my eardrum.

However, I don't think warm evenings and uncomfortable hot nights always go hand-in-hand. A dry clear spell with little wind might have a very hot daytime maximum and continued warmth into the evening, yet once the sun goes down the temperature drops significantly leading to a fairly pleasant night. In contrast those hot humid spells with large amounts of cloud can give evenings that aren't particularly pleasant for outdoor activities, yet also give hot stuffy nights.

[Devon-Nelly]

I think theres a possible connection with the European monsoon and the british summer.

The euro monsoon normally occurs in stages from Mid-May till Mid or Late June, i've noticed in most years when a mostly settled May occurs a disturbed summer normally follows, more often so in June and July as the Monsoon arrives in the summer instead of late Spring.

But when the Euro monsoon kicks in as it normally does a typical or even warm summer normally follows.

It could be just utter nonsense but i believe there has to be some connection there and that some summers dont materialise very well due to other factors (e.g La Nina) developing/changing around that period.

[Thundery wintry showers]

The westerlies do tend to kick in during June, and it's those westerlies that tend to bring lots of frontal activity and cool cloudy wet weather to Britain and the "monsoon" to the near-Continent.

Often a late arrival of the westerlies does seem to lead into cool cloudy wet summers. For instance there were many examples in the 1960s and early 1970s, also 1986, 1988, 1992 & 1993 were fairly good examples.

However, in the summers of 1975, 1976 and 1995, the westerlies didn't get into gear in June (the cool cloudy weather of early June 1995 came from northerlies and a mid-Atlantic block), and they didn't really get going in July either, setting the UK up for a hot sunny August. And it can also happen the other way for August- take 2006 for example, when westerlies only briefly took over in late June, were almost entirely absent in July, but then got going in August.

Early arrivals of the westerlies also bring mixed results. Westerly dominated Junes in 1955, 1983, 1990 and 1991 were followed by hot July/August periods but westerly dominated Junes in 1987, 1998 and 2002 led into very "westerly" type summers.

[Solar Cycles]

Well just a case now, of who will be the first to post "Is summer over". :o

[Thundery wintry showers]

Global warming is measured best by mean temperature not max temperature. In much of northern and western Britain the summers of 2003 and 2006 were warmer than the summer of 1995, entirely due to much higher overnight minima. One often-overlooked aspect of Summer 1995 is that while the daytime maxima were generally outstandingly high, the overnight minima were unexceptional as clear skies led to relatively cool nights. In contrast the greater wind and cloud cover of Summer 2003 led to some warm stuffy nights.

[SP1986]

I agree there Ian, thats why 2003 sticks out in my mind more than 1995. Although my rather qualitative recollections of 1995 were playing football on a field in primary school and nearly every day seemed unbearably hot, I dont as such recall the night temperatures but I can imagine the relatively cool temperatures. 2003 I remember more clearly because it's more recent and I took quantitative measurements of that year. There were many cloudy night resulting in frequent minimas of 17-18C. I recorded an all time temperatures minimum record here when we recorded a minimum of 24.7C in July. Very remarkable and I don't think it's year that will be so easily surpassed at least here in the west.

[J07]

I remember August 2003 pretty well, I thought it was incredibly hot and incredibly humid. I found some figures though for Heathrow and was very surprised. It was hot, for sure, but nowhere near as humid as I thought I remembered. Most nights dipped below 20C at some point. Dewpoints of 20C+ were not as common as I thought. Humidities during the middle of the day were about 40% on the hottest days in early August.

Again, I suppose an example of where people from mid and higher latitudes mistake heat for humidity.

I did see one observation where Heathrow was 34/20. That is hot, but not humid. The dewpoint being over 17C makes it feel sticky, but this sort of thing would be very commonplace in the subtropics and would not be considered humid.

I did feel quite unwell during the worst of the period though, and perhaps it was exasperated by being unable to make the house cool. And I probably am not cut out for hot weather. If I can't handle those conditions, I would probably die if I moved to Brisbane, which isn't even in the tropics.

[SP1986]

I remember August 2003 pretty well, I thought it was incredibly hot and incredibly humid. I found some figures though for Heathrow and was very surprised. It was hot, for sure, but nowhere near as humid as I thought I remembered. Most nights dipped below 20C at some point. Dewpoints of 20C+ were not as common as I thought. Humidities during the middle of the day were about 40% on the hottest days in early August.

Again, I suppose an example of where people from mid and higher latitudes mistake heat for humidity.

I did see one observation where Heathrow was 34/20. That is hot, but not humid. The dewpoint being over 17C makes it feel sticky, but this sort of thing would be very commonplace in the subtropics and would not be considered humid.

I did feel quite unwell during the worst of the period though, and perhaps it was exasperated by being unable to make the house cool. And I probably am not cut out for hot weather. If I can't handle those conditions, I would probably die if I moved to Brisbane, which isn't even in the tropics.

I do remember quite well debating on here (in its first year), whether dewpoints would be high enough for thunderstorms and you're right - in reality they never went much above 17 or 18C. Of course when the sun is shining and the temperature is high and realtively high - it can certainly feel muggy. There was one exception in my experience - August 10th brought dewpoints of 22C on the morning of the thunderstorms.

[J07]

A further point to the previous post: I found only 3 nights in Heathrow with minima of at least 20C, and these were 20C exactly. I really expected more than that.

I think this adds to "The Myth of British Humidity". We think our hot summer weather is more humid than it actually is. I remember posting an NZ observation a while back where it was something like 35C with RH of about 10%. Someone responded saying that if it happened in the UK, the humidity would be about 70%. I think that is really unlikely, and borderline impossible. It would be 35/29, which would be horrendous even in a tropical wet season.

I also think that people believe we (as in the UK) get more 20C+ minima in summer than we believe. This is likely because if the temperature does not fall below, say 17C, it probably will feel very hot inside our houses and we will struggle to sleep. If we heard that the minimum was actually 17C, it would be hard to believe.

I was in south wales in August 2003, and am amazed to see that cardiff's high was 28C and low was 18C. In my memory, you could add a few more degrees to those and it would be believable. The dewpoint did reach 20C at one point though, which may explain why it felt so sticky.

July 2006 had a better range, which surprises me a little....I did not remember it being quite as humid. However, it did see 28/20 one day early in the month. That is really warm, and hard to bear. August 2003 worst TT/Td combination was 27/20, again which is sticky and hot. These correspond to relative humidities of 60-65%.

But this stuff would be truly typical temperatures in the subtropics for several months of the year.

I know it seems odd to compare Britain to the subtropics, but I think we really overstate the humidity of our summers. Dewpoints of 20C+ are, and will remain, challenging to obtain, and clearly even in the most exceptional months are only attainable on a few days....

[SP1986]

The problem is its not always about dewpoints - relative humidity is one thing, actual humidity is another, and even if the dewpoint is 16 with a TT of 25C the humidity can be different, nearer 80% - It doesn't always follow the rule book as ive mid bogglingly found out a few times before

[J07]

25/16 gives a RH of 57%. I don't know what you mean by "actual humidity". Unless you mean specific humidity, which isn't really used much at all.

In order to get an RH of 80% with 25C you need dewpoints of between 21C and 22C.

[SP1986]

25/16 gives a RH of 57%. I don't know what you mean by "actual humidity". Unless you mean specific humidity, which isn't really used much at all.

In order to get an RH of 80% with 25C you need dewpoints of between 21C and 22C.

specific humidity yes - relative humidity is used to calculate dewpoints because it is relative to the dryness or moistness of the airmass - thats why is doesn't always give the true picture - especially if its sunny and humid for example - most of the time though its pretty much spot on because airmasses we get in the UK are usually cloudy and wet.

[J07]

But all these different measurements do not change the amount of water vapour in the air. It's just different ways of looking at the same issue. If the temperature is 25C and the RH is 57%: then the dewpoint is 16C, the specific humidity is blah, the wet bulb is blah, the absolute humidity is blah, the vapour pressure is blah....and so on. None of it changes the character of the airmass. True, they have their strengths and their weaknesses. But if we just stick to "absolute" measurements like TT and Td, and maybe Tw then we can compare across the world. If Darwin is 34/24, then we can directly compare that to Cardiff being 27/20.

Besides, the heat index and humidex tend to happily use just the RH or dewpoint combined with the dry bulb to calculate a "feels like" temperature. If they added more variables it would make little difference since they are all interdependent anyway.

[butler_son]

I'm dreading the summer. In 2006 my bedroom got to 40ºc and remained in the 30's till late October. I do not want to experience that again for a while!!!!!

That sounds very much like what I experience down here - it's certainly never cold in the height of summer, and my bedroom window is south-west facing (ish), so i get a very hot sun coming into my room, in excess of 30 easily unless I do some extreme ventilation! There have been times when it's just been unbearable, even when not even wearing a T-shirt, I'm still sweating buckets!

Though this won't stop me wanting a long hot summer! June 2006 again please! Not a day below 25, most over 30 I think...

[J07]

Though this won't stop me wanting a long hot summer! June 2006 again please! <_< Not a day below 25, most over 30 I think...

Alarm bells, ring-a-ding-a-ding!!!!!! A good month, but let's not get carried away.

Boscombe Down, which is near enough, had 23 days in June 2006 which failed to make 25C. 0 days of 30C were recorded.

Unless you meant July 2006? Which still had 14 days that did not make 25C, but 5 days of 30C or more.

Nottingham, 23 days that did not make 25C, 0 days over 30C in June 2006.

In July, 15 days that did not make 25C, 0 days of 30C or more.

....were in you in Spain or something?

[butler_son]

Alarm bells, ring-a-ding-a-ding!!!!!! A good month, but let's not get carried away.

Boscombe Down, which is near enough, had 23 days in June 2006 which failed to make 25C. 0 days of 30C were recorded.

Unless you meant July 2006? Which still had 14 days that did not make 25C, but 5 days of 30C or more.

Nottingham, 23 days that did not make 25C, 0 days over 30C in June 2006.

In July, 15 days that did not make 25C, 0 days of 30C or more.

....were in you in Spain or something?

It was hot...I think I had some cheapo measuring thing back then tbh though! It was definitely June, and wasn't either of the 2 locations on the avatar...won't make a lot of difference, nearest places were Blandford Forum and Dorchester, DT11! I remember the heat just built and built, where I was was in the middle of a valley too. I'd be very surprised if 23 days failed to reach 25 degrees, and surprised if 30 wasn't reached once! Still, I'm no anorak, and I was 16/17 at the time... Either way, a repeat performance is very much allowed! <_<

EDIT: I've just had a look at the BBC Archive for the June 2006 summary and seems odd because I don't remember much rain whatsoever where I was...and it could well have been 2005 for all I can remember, but I reckon it was 2006...though I could well be wrong...

Edited April 12, 2009 by butler_son

[GRHinPorts]

It was hot...I think I had some cheapo measuring thing back then tbh though! It was definitely June, and wasn't either of the 2 locations on the avatar...won't make a lot of difference, nearest places were Blandford Forum and Dorchester, DT11! I remember the heat just built and built, where I was was in the middle of a valley too. I'd be very surprised if 23 days failed to reach 25 degrees, and surprised if 30 wasn't reached once! Still, I'm no anorak, and I was 16/17 at the time... Either way, a repeat performance is very much allowed!

EDIT: I've just had a look at the BBC Archive for the June 2006 summary and seems odd because I don't remember much rain whatsoever where I was...and it could well have been 2005 for all I can remember, but I reckon it was 2006...though I could well be wrong...

Both June of 2005 and 2006 were hot...In 2005 though it was the 2nd half that saw most of the heat (it was the warmest 2nd half of June since 1976) where as the first half was on the coolish side.

June 2006 here in the south was very hot pretty much throughout from my memory. May was a pretty grotty month but a big high pressure arrived on the 1st and stayed until about the 12th with day time temps regularly exceeding 25 and sometimes getting beyond 30. The period 12th-25th was then cooler with a storm arriving on the night of the 20th-21st but still some days would have reached 25. The month then ended with another hot spell where I would think most days reached 25 and some maybe 30.

Edited April 13, 2009 by GRHinPorts

[Thundery wintry showers]

June 2006 had a north-south split. The south was warm, dry and sunny for most of the month and it was locally the sunniest since 1975. However, I remember that in Leeds there was a very continental-style first 12 days, with consistent warm sunshine and occasional showers, and severe thunderstorms broke out on the 12th, and then the rest of the month was mainly dry and cloudy with westerly winds. Many other northern areas had a similar progression, and thus sunshine was only a little above normal.

In July 2006, the pattern of the 1st-12th June (frequent high pressure and southerly winds) persisted for most of the month, and in Leeds it was like spending a month in central continental Europe. Mean maximum temperature was 5C above normal and sunshine about 60% above, and there were also occasional showers and thunderstorms.

Strangely, I found the hot spells of June and July 2006 far more bearable than the less extreme heat at the end of July 2008- and I was living in the middle of a fairly large city (Leeds) in Summer 2006. Humidity and warm nights were probably the main factors in making the July 2008 heatwave unpleasant.

Second half June 2005 was remarkable in both Lancaster and Cleadon (where I spent roughly half-and-half of the period)- again, frequent hot sunshine and occasional thundery outbreaks, the storms of the 19th in Cleadon were particularly unusual in intensity for the North East.

[Derp Patrol]

Last year we hardly got any warm and settled weather here, apart from the end of July and sometime in August where it only just touched 30 for a day or two, and then it was only about 25-28C for about 10 days and then back to cloudy skies and rain

[GRHinPorts]

Last year we hardly got any warm and settled weather here, apart from the end of July and sometime in August where it only just touched 30 for a day or two, and then it was only about 25-28C for about 10 days and then back to cloudy skies and rain

Yes last year the only decent hot weather came in the first half of May when it regularly reached 25 degrees here in the South.

Although I do recall that hot spell you refer to at the end of July. It was very humid and pretty brief.

[willinkent]

I hope so........ i need to get rid of my pastyness....... ahhhhh............