Relativistic

I don't want Winter to feel like it's ended early. Some of us like the dark, let it persist for as long as possible I say.

This might be of interest. I've plotted the dates of full Moons and the CET daily data together, for 2016. The first two full Moons of this year definitely coincided with temperature spikes. The fifth full Moon also saw a reasonable spike, and the plume in July coincided (perhaps the wrong word to use?) very nicely with the seventh full Moon of the year. The other full Moons occurred around slight spikes, but these are not as pronounced.

I'm surprised that such little fuss is being kicked up about the alleged 34.4C at Gravesend today. The hourly temperature readings for Gravesend on the Met Office website show nothing above 32.0C, surely it's got to be pretty bloody difficult to spike to 34.4C and sink back down again within an hour? http://www.metoffice.gov.uk/public/weather/observation/u10k8kx5v Perhaps it is possible but until the Met Office release more detailed readings (rather than just hourly ones) then I'm going to remain sceptical.

It's interesting to look at the mean CET for astronomical Summer (AS), which, for simplicity's sake, I have defined as being 21st June to 20th September for every year (obviously this isn't totally accurate). By taking the mean CET of every day within this range, provisionally the AS of 2016 has a mean of 16.7C. However, it looks as if by the 21st we may be up to 16.8C, which overall would rank 2016 as joint 14th warmest on record (going back to 1772). The other years that equalled this were 1779, 1868, 1899, 1959, and 1975. Interestingly, no AS has ever recorded a mean CET of 16.7C, despite the fact that there have been five years at 16.8C and six years at 16.6C. It's possible that 2016 will be the first year to do this. By calculating the meteorological Summer (MS) mean in the same way (simply take a mean of all days), we find that MS 2016 has a mean of 16.4C; quite a bit lower than a possible value of 16.8C for AS 2016. For a particular year this is not unusual however, and it's actually become more common in recent decades (starting circa 1920) for this to be the case. The graph below shows the value for a year's MS minus its AS (y axis, years are on the x axis). This is to be expected, since September has warmed since 1772 (especially so in recent decades), while June has not. Something that I thought was noteworthy when looking at Summers in this way was that 1995 was easily the warmest of the lot (17.7C), beating 2006 in second place (17.4C). Summer 1976 "only" ranks fifth (17.2C).

This says that temperatures only maxed out at 32C? http://www.metoffice.gov.uk/public/weather/observation/u10k8kx5v

With regards to breaking records, this hot spell couldn't have happened at a more perfect time. The 13th is the first day of September to have never recorded 30C (record prior to today was 28.3C), and neither have the 14th nor the 15th (records of 28.6C and 28.9C respectively). The records for the 16th and 17th (when we expect cooler air to move in) both breach the 31C mark!

Very interesting... September 1851 was generally cool. September 1795 (a 56 year gap from 1851) is the 5th hottest on the CET (16.0C). September 1740 was the only month warmer than average in 1740 (14.0C), the coldest year on the CET record. September 1685 is the 19th coldest on the CET record (11.5C). Perhaps this time we were on the "wrong" side of a meandering jet stream? It's an interesting pattern (and a good spot!) but it does become a little inconsistent.

I did construct an argument but did some calculations and realised that it was totally flawed! I have found this link though, which says the following: "For reasons not yet fully understood by scientists, it is thought that smaller particles (less than 100 micrometers) acquire a positive charge, while larger particles gain a negative charge." http://www.aharfield.co.uk/lightning-protection-services/how-lightning-is-formed So it looks as if it is still a mystery waiting to be solved.

Will be very interesting to watch the CET over the next few days, as we could achieve a three day spell with a mean of 20.0C+. If so, it would be the latest ever in a calendar year. The current latest is 7th-9th in 1898 (20.5C), so we may beat this by five or six days! This feat last occurred in 1906 (1st-3rd was 21.4C, the warmest such period on record). If 2016 pulls it off it will only be the sixth year ever to do so. (The others were 1780, 1824, 1880, 1898, and 1906.)

It's 8pm and almost totally dark here, even with perfectly clear skies. I went abroad for nearly a week and in that time we've lost nearly half an hour of daylight, was a bit of a shock being back today. We're really on the slide now.

I'll take unseasonably cold weather all year round. For October, I want the Thames to freeze over.

Makes a change. The wind picking up, the clouds rolling over, the rain pitter-pattering, and the earliest evening darkness in a long time. There's something so nice about it. Really in the mood for Autumn now...

December suffered a double whammy. The new average loses December 1981 (0.3C) and gains December 2015 (9.7C).

Once again this year, near record heat is being forecast. The week-long period as forecast above from the 5th-11th looks very warm indeed, and would have a mean of 19.0C. Only two years have had a September week as hot or hotter, these being 1898 (heat peaked 3rd-9th; this period holds the record for the hottest September week ever, at 20.0C), and 1906 (1st-7th was 19.0C). Of course, the 11th is a long way away yet, but even with a downgrade approaching 1C we'd end up in the top 10.

Ah I see, no worries!

Weird, my program spits out 17.9C as the value to the 10th in 1795, with only 1865 (18.0C) and 1898 (18.2C) above it. Seems to be consistent with my spreadsheet as well... Whatever the case, both September 1865 and September 1898 started out very hot!

I have 1st-10th being the warmest in 1898 (at 18.2C), which was then 17.4C to the 20th, and finished at 15.2C? September 1852 finished at 12.9C. I also have the warmest 1st-20th period as 1865 at 17.8C, and 1852 in the same period as 13.8C? Forgive me if I've made a massive cock-up here!

We didn't quite make it with this one. We met the 17.0C+ criterion, but both the 23rd and 24th finished with daily means of 20.2C. Close, but no cigar. The second half (16th-31st) finished as the 15th warmest on record (17.6C), between 1807 (17.5C) and 1857 (17.7C).

It still sticks out like a sore thumb! Quite a turnaround given how cool it was prior to the heatwave.

I don't know if Crucible72 was referring to his/her own location, or the CET specifically, but it is true to say that for the CET zone this will be the first time all three Summer months have been above the 81-10 averages since 2003. In fact, for June, the CET was well above average, and places 64th warmest since the record began. Most of the warmth however was concentrated in the first half of the month, so perhaps people's opinions are skewed by the second half of the month. 1st-15th: 15.6C (61-90 mean is 13.7C, 81-10 mean is 13.8C) 16th-30th: 14.9C (61-90 mean is 14.6C, 81-10 mean is 15.1C) As you can see, the first half was well above the 81-10 average, the second half was a touch below. BFTV's post here may be of use for visualising this (the first graph): The nation as a whole was above average also:

So far we have one day this August whose provisional daily CET mean is greater than 20C (20.5C on the 23rd), and it's not impossible that this could end up sub-20C after corrections. With the possibility of this month ending up at 17C or above, I thought I'd look to see how many Augusts have managed an overall mean of 17C+, but not managed any 20C+ days. Only five Augusts have managed it: - 1801, overall mean CET of 17.1C. - 1802, 17.2C. - 1819, 17.4C. - 1944, 17.0C. - 1991, 17.1C. (It's worth noting that 17C+ Augusts average four 20C+ days. The most ever was 14 in 1997.) I'd say the odds of joining the club aren't in 2016's favour because there's still a good chance of finishing below 17C, and we also require a reasonably large downward correction of 0.6C on the 23rd (they do happen though).

Looks like, overall, a very warm second half of August. Combining the provisional data with your estimates for today and the days to come yields a second half CET (16th-31st) of 18.0C, which would place as the joint 7th warmest on record, with 1826. Those that rank above this are: 1947: 19.4C 1955: 19.3C 1984: 18.9C 1995: 18.6C 1997: 18.3C 1976: 18.3C Some very famous Summers there.

I actually take cold showers most days of the year (even in Winter) so my body has adapted to it. In weather like this it works temporarily but I soon warm up again. I'm not one to moan too much about the weather (I enjoy basically every weather type that everybody else hates) but the weather at the moment is the most unpleasant I can remember for perhaps four years (Jersey, late July 2012 heatwave).

Tell me about it. Earlier a nearby station hit 28.3C with a dew point of 19.1C. I'm now sitting in my room at 26C with the fan blasting my face and the windows wide open (both of which are seemingly making no difference whatsoever), and the dew point outside is 18C. Horrific.

I must be the only person in the south-east who wants to move away. The heat always seems to stick here. It seems to be a recurring theme this August, seeing temperature charts where the south-east corner is in the reds/ deep oranges. As to whether this Summer has been what most would describe as "good" (hot, dry, sunny), I would say the following for this location. It has certainly felt warm/ hot on a number of occasions (more often than I would expect, often maxing out at 24C), and has been extremely dry. The grass seems to be brown absolutely everywhere, which I expect to a certain extent for July and August but this year it seems to have been very noticeable. The ground is like concrete at the moment. A nearby floodplain had deep, gaping cracks forming in it last time I went there. In terms of sunshine July and August have felt much more normal. June was extremely cloudy but felt on the warm side still. The above is certainly not what I would expect given my experiences of past Summers. Granted my memory for weather events doesn't go back too far (2010... ish), but the only thing comparable seems to be July 2013, which seemed hot and dry for weeks. And that was the 10th hottest July on record (CET). I've said it before two or three times, but this talk of minima dragging up the averages simply isn't true, at least across the CET zone (which is pretty extensive). Both maxima and minima have been comfortably above average this Summer. I'll post the links once again (must be the third time now) just so that people can check for themselves. Min: http://www.metoffice.gov.uk/hadobs/hadcet/cet_info_min.html Max: http://www.metoffice.gov.uk/hadobs/hadcet/cet_info_max.html I know warm temperatures alone for most people don't constitute a good Summer, but the talk of minima skewing this Summer's averages is nonsense and keeps coming up in conversation, so I'm just pointing that out.