Relativistic

July to November: 1807 (17.1C to 2.9C, 14.2C drop); August to November: 1807 (16.9C to 2.9C, 14.0C drop); September to November: 1795 (16.0C to 4.5C, 11.5C drop); October to November: 1807 (11.4C to 2.9C, 8.5C drop).

You mean back.

Yes, only 5 subzero CET maxima in November. 27th 1890 (-0.3C) 28th 1890 (-0.5C) 24th 1904 (-0.3C) 23rd 1993 (-0.5C) 28th 2010 (-1.0C) So the earliest proper ice day on record is 23rd November 1993.

The earliest ice day was 7th November 1791 (-0.6C) (see RJS's post on page 1), although it's possible that October 1740 saw ice days (daily data isn't available unfortunately). The 28th November 2010 was the only day to break a date record in that month (-4.0C). The same date saw the record low November CET maximum (-1.0C).

An interesting statistic from last November is that the first half (1st-15th) was the second warmest on record (11.4C), behind 1938 (12.0C). The 10 warmest first halves of Novembers are as follows. 1. 1938: 12.0 2. 2015: 11.4 3. 1994: 10.6 =4. 2011: 10.5 =4. 1978: 10.5 6.1818: 10.4 =7. 1817: 10.0 =7. 1899: 10.0 =9. 1852: 9.9 =9. 1982: 9.9 So why am I saying this? The value for the half-month 16th-31st December 2015 was 10.4C. The second half of December 2015 would rank joint 6th place in the list of warmest first halves of November! That's just bonkers! It also trounces all second halves of November, the warmest of which was 1994 (9.6C).

The mornings have been very dark in Brum the last few days. Old Joe (the uni clocktower) has his clock face lit when it's dark enough (I assume it's on a sensor), and it's staying lit to around 8am at the moment. Probably aided by overcast skies mind. I am enjoying these dark mornings, but won't be sad when the clocks go back. That change in the evening darkness marks the start of my favourite time of year for daylight hours, ending at the beginning February.

3.6C. Extremely cold.

Temperature overnight fell to 14C in my room, no heating on yet. However, relative humidity is around 80% and my textbooks are curling up because of the moisture. Will have to turn it on at some point to stop damp patches and mould. Really doesn't help that no sunshine gets into my room at this time of year.

The 21.3C value on the 14th was the joint seventh warmest September day in recorded history (the 8th in 1898 was also 21.3C). Only the 21st in 2006 was as warm/ warmer at a later stage in the month (21.4C). We also got the latest 3-day period ever to have a mean of 20C or above: the 13th-15th averaged 20.3C. The next latest was 7th-9th 1898 (20.5C), so this record jumped almost a week. At 17.5C, the first half (1st-15th) was the third warmest on record, behind 1865 (18.1C) and 1898 (17.6C). At 14.6C, the second half (16th-30th) was a less remarkable (although still noteworthy) joint 14th warmest on record. Other years to record this figure were 1795, 1875, and 1999. The record is 16.5C, in 2006. By minima, September 2016 was third warmest on record (12.1C), behind 1949 (12.2C) and 2006 (12.8C). By maxima, September 2016 was seventh warmest on record (20.0C). The record is held by 2006, at 20.9C. Below shows the mean CET to each date for 2016, and how these values compare to the five warmest Septembers for which daily data is available:

Looks like September has been confirmed at 16.0C, making it joint 5th warmest with 1795. Let's hope this isn't a bad sign for Winter 2016, January 1796 was the third mildest on record (7.3C)

Indeed, the 31st July 2015 was the 5th coldest July minimum in CET history!

I actually emailed the Met Office about this just after it happened, and yesterday I received a reply. "The following is from a climatologist within our National Climate Information Centre. I agree that the difference between the highest hourly value and the daily maximum seems quite large. However we have studied the 1-minute data from Gravesend and are confident that the observations are correct. What appears to have happened is that the wind direction veered from around 60 degrees to around 120 degrees for a period of around 20 minutes (between 14:10 and 14:30) and that as a result the temperature rose fairly steadily to eventually reach 34.4 deg C and then dropped away again. It seems to be coincidence that this peak occurred between two successive hourly observations. I will discuss this with my colleagues and hopefully we will be able to add another graph and/or commentary to our event summary to provide support for the observations. This may take a week or so. For information, the existing summary is here: http://www.metoffice.gov.uk/climate/uk/interesting/september2016_temperature " Hopefully that should clear things up.

We’re two thirds of the way through the month now, and using the provisional figures we’ve dropped below 2006. This puts us in 5th position. Warmest Septembers to the 20th: 1. 1865: 17.8 2. 1898: 17.4 3. 1795: 17.0 4. 2006: 16.9 5. 2016: 16.8 6. 1780: 16.7 =7. 1926: 16.4 =7. 1947: 16.4 =7. 1949: 16.4 10. 1929: 16.2 Below I have plotted, for the 5 warmest Septembers for which we have daily data, the mean CETs to each date in the month. Alongside them I have plotted September 2016. September 2016 still right in the mix. I'll update this at the end of the month, or before should anything noteworthy occur.

A Thames freeze-over late on. A cold 7.9C.

30 years averages for 1st-21st March/ December: 1781-1810: 4.2/ 3.4 1791-1820: 4.6/ 3.5 1801-1830: 5.1/ 4.0 1811-1840: 5.2/ 4.6 1821-1850: 5.3/ 4.9 1831-1860: 5.0/ 4.6 1841-1870: 4.8/ 4.8 1851-1880: 5.0/ 4.3 1861-1890: 4.8/ 4.0 1871-1900: 4.9/ 3.9 1881-1910: 4.7/ 4.4 1891-1920: 5.0/ 4.9 1901-1930: 5.3/ 4.7 1911-1940: 5.3/ 4.6 1921-1950: 5.3/ 4.6 1931-1960: 5.3/ 4.8 1941-1970: 5.2/ 4.7 1951-1980: 5.2/ 4.9 1961-1990: 5.3/ 4.8 1971-2000: 6.0/ 5.2 1981-2010: 6.2/ 4.8 The averages have really diverged in recent years owing to December's cooling trend and March's warming trend. Many of the 30 year averages were quite similar, with the 1841-1870 averages both at 4.8C. No March averages were colder than their corresponding December averages.

Agree with some on here, it's still t-shirt and shorts weather for me here in Birmingham. If you're out and about 16C isn't cold at all.

I'm a serious weather enthusiast, I appreciate almost every weather type you can possibly think of (there is only one thing that springs to mind that I dislike). I'll admit that to like such weather is unusual among the general populace, but wouldn't you expect to find people who appreciate all kinds of weather on a weather forum? My oddness is just my enthusiasm, simple as. People who don't like cold are actually more "odd" among our community of weather enthusiasts here; the forum goes nuts in Winter, and by contrast in Summer it feels a bit dead. Personally, I love weather I can really feel and see, I love experiencing the elements. The atmosphere is a truly amazing thing. Today was great, I could feel the wind rushing over my skin and I could see the clouds rolling over, exhibiting chaotic and fascinating patterns as the air sloshed around high above. (As someone who studies theoretical physics, chaotic systems and complex fluid dynamics are just some of the things that really fascinate me. I love meteorology, and cloudy skies in particular, for these reasons.)

Days like today are some of the best of the year IMO. It's 14C, overcast and breezy, which for me is nigh on perfect for wearing a t shirt and shorts when you're out and about. Feels very fresh, you can feel the wind passing over your skin and keeping you at a comfortable temperature. Overheating is not a problem, and neither is sweating. I also love to look up on days like today, seeing the clouds roll over and looking at the myriad patterns that can be seen within them as they do. Wonderful stuff, and we should have more to come in the weeks ahead. Then we have the first frosts to look forward to, and very quickly we will descend into Winter...

First half is provisionally the third warmest on record (behind 1865 and 1898), even September 2006 was lower by this stage (17.2C).

You have to experience at least one in your lifetime though... Would you not agree?

Preferably the coldest on record, with exceptionally deep snows . How about a repeat of 1683/84? As the days get shorter it'll be harder to contain myself when it comes to Winter talk.

The provisional value for yesterday was 18.8C, which gives the mean for the 13th-15th as 19.8C, so just missing out. But corrections may see to that. Even if this was to be the final figure, nothing as warm has occurred as late in the year, so as short, sharp September hot spells go, it's been pretty remarkable. The most comparable transient hot spells were 17th-19th September 1926 (19.7C, perhaps a figure to aim to beat after corrections), and the 28th-30th September 2011 (19.5C, which, frankly, blows my mind).

Autumn, I welcome you with open arms! After what was one of the longest, driest and warmest Summers I can remember, to see the clouds rolling over and to hear the wind rushing through the trees is quite simply wonderful; the change is here (and hopefully it sticks around). So much fresher out there, not even 16.0C! Been out for a walk and I didn't sweat out an ocean's worth of water! I actually can't remember the last time we had a day as overcast as this. The downpour last night should help to ameliorate the situation with the ground, it's been like concrete for weeks. A friend of mine has had to be cautious when walking his dog in a nearby floodplain because it's legs were getting stuck down the enormous (both wide and deep) cracks that have opened up there.

The autumnal equinox this year occurs on the 22nd September at 2:21pm GMT (so 3:21pm BST). We're less than a week away , bring on Winter!

So provisionally we have 19.9C and 20.7C as the daily values for 13th and 14th respectively, requiring a value of 19.4C or higher today to achieve what would be provisionally the latest ever 3-day spell with a mean of over 20C. The provisional mean of 20.7C yesterday was the joint 13th warmest September day on record (the other being 4/9/1880). There are only two days on record that recorded higher daily means at a later date in the month: these were 19/9/1926 (20.9C) and 21/9/2006 (21.4C).