First summer in 4 years without 34C being hit?

[qwertyK]

I believe this is the first summer in 4 years without 34C or 35C being hit somewhere in the UK. Maximum this year is 33C. This summer really is dissapointing, but at the same time, it's probably just average in terms of long term weather? Like looking at some of the tempreature anomalies in parts of europe, records being broken, its nice to have something thats not extreme here

[LetItSnow!]

I remember averaging out every yearly maximum temperature from every year from something like 1900 & the result was exactly 32.2degC. I think this years maximum temperature so far is about 32.4 or something like that, so a very normal yearly maximum temperature for the past 100-150 years. We’ll see if this gets broken but I don’t think it will personally. 

[Derecho]

9 minutes ago, LetItSnow! said:

I remember averaging out every yearly maximum temperature from every year from something like 1900 & the result was exactly 32.2degC. I think this years maximum temperature so far is about 32.4 or something like that, so a very normal yearly maximum temperature for the past 100-150 years. We’ll see if this gets broken but I don’t think it will personally. 

Knowing recent summer months, our maximum will be below 30C until the 31st of August where we get a sporadic 1 day heatwave that beats it (still clearly remember that unusually hot day at the end of July last year in an otherwise cool month).

You are probably right though. It's the lack of thundery plumes that I feel have been a let down this year.

Edited August 16, 2021 by Quicksilver1989

[LetItSnow!]

Here is a graph of every annual maximum temperature from 1875 to 2021 (as of now)

The average of all years combined is 32.3.

The graph provides insight into the variability. The latter part of the 19th century provided rapid swings in annual maxima. There were many years that topped out into the 33-35 region, particular the 1890s, but they were interspersed with much poorer years, like 1879 & 1890. Both notable, the first was a measly 26.8 & the latter only 28.3… recorded in September! Both summers were poor, but 1879 was extraordinarily poor. 
 

The first half of the 20th century saw a gradual incline in readings in the mid-thirties, though there were still years that failed to reach/exceed 30. A notable change started in 1962 & lasted until 1988. This period, bar the odd exception, saw an unusually high frequency of years that failed to reach 30, or barely scrape it. 1962-1967 is a good example. 

The trend shifted in 1989 with the first truly hot summer since 1983, then 1990 came & broke records. It then settled back to average between 1991 to 2002, then came the remarkable heatwaves in 2003 & 2006, but aside from these years, most years of the 2000s tended to record very normal annual maxima, this period lasting until 2014. In 2015, something very unusual started to occur. Alone, 2015, while notably hot, would not stick out too much like a sore thumb in the records, but it began a period from 2015 to 2020 that’s never been seen before in recorded history. You can see this clearly in the graph. 
 

If we assume that 2021 won’t exceed 32.2 then it will actually be ever so slightly below the all time average, therefor breaking that extraordinary run. If this happens then who’s to say if this is the start of more normal annual maxima over the next 5-20 years or just a blip. We’ll find out. 
 

Apologies if this is a little off topic, but you should know by now I love a statistical analysis!  

 

Side note: Some of the more extreme readings from pre-1940 make me wonder just what type of temperatures the same set up would give now. 1911 recorded 36.7!

[Sky High]

Thanks for the graph and insight. It will be interesting to see how the next few summers unfold. Were the last few years a blip and will we see a few cooler summers in the future?

[qwertyK]

Actually I think this would actually be 5 years not 4, as wasn’t 34C recorded in 2016 in September somewhere?

 

so theoretically we could get a spell of hot weather in September but it’d have to be pretty exceptional. It’d funny how Southern Europe is ridiculously hot in places yet none of that hot air has made its way north. 

[mb018538]

On 17/08/2021 at 09:32, qwertyK said:

Actually I think this would actually be 5 years not 4, as wasn’t 34C recorded in 2016 in September somewhere?

 

so theoretically we could get a spell of hot weather in September but it’d have to be pretty exceptional. It’d funny how Southern Europe is ridiculously hot in places yet none of that hot air has made its way north. 

34.4c at Gravesend on the 13th September 2016.

Hottest day of the year, hottest September day since 1911, first time above 90f in September since 1949, and first time since 1962 warmest day of the year was in September. Remarkably late for such heat.

Think we've been unlucky this year, the extent of heat available to the south has been higher than any year I can remember. North Africa has been running miles above average for months - the result of this has finally been felt in the last couple of weeks in Italy/Greece/Spain/Turkey etc.

[Typhoon John]

It would be interesting to see a second graph showing the number of days per year with maximum temperature over 30c.

[BruenSryan]

1 hour ago, Typhoon John said:

It would be interesting to see a second graph showing the number of days per year with maximum temperature over 30c.

Since 1960 (may have missed 1 or a few days in some earlier years).

The 1960-2020 average is 6.8 days.

Edited August 17, 2021 by BruenSryan

[Weather Enthusiast91]

4 hours ago, qwertyK said:

Actually I think this would actually be 5 years not 4, as wasn’t 34C recorded in 2016 in September somewhere?

 

so theoretically we could get a spell of hot weather in September but it’d have to be pretty exceptional. 

Yes, I can't see another spell like that happening in September again for a very very long time. Temps above 30 Celsius are difficult to achieve in high summer, let alone during early autumn.

So it's improbable but not impossible.

From a meterological point of view, that spell during Sept 2016 was amazing. As was the autumn 2011 heatwave.

Edited August 17, 2021 by Weather Enthusiast91

[qwertyK]

3 minutes ago, Weather Enthusiast91 said:

Yes, I can't see another spell like that happening in September again for a very very long time. Temps above 30 Celsius are difficult to achieve in high summer, let alone during early autumn.

So it's improbable but not impossible.

From a meterological point of view, that spell during Sept 2016 was amazing. As was the autumn 2011 heatwave.

October 2018 was also pretty warm. What’s the likelihood of this in the near future? I mean I can’t see it this year because that time it was after a very hot prolonged summer 

[Nick L]

4 minutes ago, Weather Enthusiast91 said:

Yes, I can't see another spell like that happening in September again for a very very long time. Temps above 30 Celsius are difficult to achieve in high summer, let alone during early autumn.

So it's improbable but not impossible.

From a meterological point of view, that spell during Sept 2016 was amazing. As was the autumn 2011 heatwave.

Not sure I agree with that in a warming world. We very narrowly missed out on 30C in OCTOBER not so long ago!

[qwertyK]

1 minute ago, Nick L said:

Not sure I agree with that in a warming world. We very narrowly missed out on 30C in OCTOBER not so long ago!

That was at the very start of the month though like the 1st and only occurred because of a build up or heat from September 

[cheeky_monkey]

5 hours ago, qwertyK said:

Actually I think this would actually be 5 years not 4, as wasn’t 34C recorded in 2016 in September somewhere?

 

so theoretically we could get a spell of hot weather in September but it’d have to be pretty exceptional. It’d funny how Southern Europe is ridiculously hot in places yet none of that hot air has made its way north. 

wouldn't that make it 2012 then..2015 reached 36c..sure 2014 reached 34c somewhere? as did 2013?

[qwertyK]

Just now, cheeky_monkey said:

wouldn't that make it 2012 then..2015 reached 36c..sure 2014 reached 34c somewhere? as did 2013?

Wow, maybe you’re right 

[BruenSryan]

2014 max was 90f (32.3C) on 18 July, not 34C. 2013 did reach 34C on 1 August.

[Hirudine]

In any normal time, I would have chalked this down as a blip of a colder summer, but with the current rapid change in global weather systems, you do have to wonder if this is the first signs of the AMOC shutting down.