December CET

[rich1]

Looks like the Atlantic is going to finally shunt away the real cold stuff that has managed to linger around our region for the last week around the 15th does seem to have a fair chance of being blown away and that means that the CET will rise probably a lot back towards average if that pattern holds for any length of time.

Is what we would expect to happen in the normal run of things, but not so sure this december is in the normal run of things...the divergence in the output says to me that they are struggling a bit with the pattern for the end of next week. It wont stay cold forever but one thing I have noticed in recent times is for mild spells to be downgraded in much the same way as cold spells have been in recent winters. I think this Decembers CET will struggle to get out of the 3's at best, and as far as actual weather, uncertainty kicks in very early, which makes a change from bartlettised years where you can predict 10 days ahead no bother

[Optimus Prime]

Well I don't know what Kolds on about, the 12z is an very cold run, the period 7th-15th averages just 1.1c (well over 3c below normal)

Current CET is 2.7c according to Hadley and The CET by the 15th would end up at 1.8c this is 3.5c below the 71-000 average for the first half of December and even 3.1c below the 61-90 norm.

This would make it the coldest first half of December since 1981. And the coldest 15 days of any winter month since the first half of January 1997 (that was 1.0c for the first half)

It would then require the second half to average 8.3c for the month to come in average. It happened in 1987 with 8.6c. A CET above 6.0c would be absolutely unlikely.

Edited December 7, 2008 by Optimus Prime

[Duncan McAlister]

I probably haven't done this totally accurately, but the 12z gives a CET of 2.3 by the 20th.

If it's anywhere near right, the CET could still be in the 2's by the 20th - a real turn-up for the books and a welcome one for most on here I'm sure!

It's game on for a sub-10C year IMO

Edited December 7, 2008 by Duncan McAlister

[kold weather]

The 12z GFS, OP is also one of the coldest runs from beyond the 12th compared with the ECM/UKMO which bring the Atlantic back in to some extent. Also note I only said towards average, I didn't say I think it would reach average, just come up from where it will be by the 15th, which to be fair is actually very reasonable statement to make.

Does look like being a very cold first 10 days to December, after that though we shall see. IF the high can just hold on like it does on the 12z GFS then we are on for a very below average December but we have to wait and see.

I still think 3.5-4.5 is the best estimate, certainly do have a shot at below 2001 if we can just shunt the Atlantic out long enough.

Edited December 7, 2008 by kold weather

[Kentish Man]

First week of December stats from Climate UK

CET: (Dec 1- 7): 1.7°C (-3.9 degC)

E&W Rain: (Dec 1- 7): 21.6mm ( 95 per cent)

E&W Sun: (Dec 1- 7): 32.3hr (299 per cent)

© Philip Eden

Apart from the cold we've all talked about it has been unusually sunny.

[Nick H]

E&W Sun: (Dec 1- 7): 32.3hr (299 per cent)

© Philip Eden

Apart from the cold we've all talked about it has been unusually sunny.

Sunniest Dec ever is 2001 with 75hrs18min. We'll be well over half way to that figure by the end of Wed 10th.

[Duncan McAlister]

Hadley down to 2.6, I must admit I thought it would have taken a bigger hit but yesterday came in at 1.8, higher than I expected.

[Gavin P]

Almost one degrees differance now between Hadley and Manley. Quite unusual to see such a large deviation between the two. I'd expect at least a 0.5c reduction from Hadley at the end of the month.

Edited December 8, 2008 by Gavin P

[Joneseye]

Almost one degrees differance now between Hadley and Manley. Quite unusual to see such a large deviation between the two. I'd expect at least a 0.5c reduction from Hadley at the end of the month.

Hi Gavin,

I think it has been mentioned before that Hadley tend to have higher stations than Manley, or maybe it was the other way round? Whilst we have not had an inversion as such this month, one would expect the lower stations to have had more in the way of frost under clear skies with very little wind.

Regards

Ian

[North-Easterly Blast]

Decembers in which the second half had a higher CET value than the first half since World War 2:

1945, 1947, 1949, 1951, 1952, 1954, 1957, 1958, 1959, 1960, 1966, 1971, 1973, 1974, 1975, 1977, 1980, 1982, 1983, 1987, 1988, 1989, 1990, 1991, 1997, 2002.

Decembers 1967, 1976 and 1998 had equal first and second halves.

Looks as though 2008 may well join the list. Getting a colder second half of course means more chance of colder weather around Christmas. We have been lucky in recent years in that there have only been two Decembers in the last 17 years with a warmer second half. There were a number of uncanny examples of warmer second halves in 1983, 1987 and 1991. 1987 (8.6) the warmest second half of December in the CET series. 1991 had a CET of 7.1 for the second half after 2.3 in the first half. 1983 was also a very mild second half of December (7.4). The second halves of Dec 1974 and 1988 had CETs of 8.5 and 8.2 respectively. The above list also shows that it is rare for a colder than average December overall to have a warmer second half - only 1952 and 1960 in that list were below 4*C for the CET, and even each half of Dec 1960 was 3.5 and 4.3 respectively.

Edited December 8, 2008 by North-Easterly Blast

[Michael Fishermans Friend]

I've got a sneaky feeling you can add this year to it, GFS is certainly showing somewhat milder conditions next week, but maybe HP close to the UK over Xmas maybe?

[Polar Continental]

A very cold first week at this station with a mean temperature of just 1.1c, my records don’t go back far enough to compare with anything beyond 2005, but this must be breaking some records now I would think.

Paul

[Kentish Man]

Hadley is on 2.6C today (Dec 1 - 8 )

Edited December 9, 2008 by Kentish Man

[Weather-history]

22nd Nov - 8th Dec CET: 3.2

compare that to

22nd Nov - Dec 8th 1879 CET: -1.1

22nd Nov - Dec 8th 1979 CET: 9.3

Edited December 9, 2008 by Mr_Data

[eddie]

The Hadley CET (1st-10th) is 2.7C.

[Weather-history]

I'm beginning to wonder if one or two places (Eskdalemuir for example) could turn out a sunnier December than August?

Virtually cloudless here currently, something that didn't happen in August!

[Optimus Prime]

Should be fairly interesting how cold the 1st half of December will come in as. Looks like today - 15th will average somewhere around 2.3c. With the current CET at 2.7c, maybe as low as 2.5c by the 15th with low maxima and so the coldest first half of December since 1991 (which averages 2.1c) 

What needs bearing in mind is the second half of December 1991 was very mild at 7.1c and so the month overall was only slightly cool. 

The second half would need to come in at 7.6c for December to be average (71-000) quite likely in a warming climate.

[Gavin P]

Dec 1991 was a rather differant pattern. The cold early on was more inversion cold and at no time was there much in the way of high latitude blocking.

[Stu_London]

The high res part of the 06z gives an outrun of 2.6C to 17th.

I would say the final figure should come in between 3.5C and 4.5C, although could be lower if the milder weather proves to be an FI illusion

[Shunter]

Phillip Eden site reporting 1.8c CET 1-10 Dec this morning. Not bad considering it was running at 8c this time last year !

[Gavin P]

No change on Hadley yesterday, despite it being very cold through much of CET land and starting with a hard frost;

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

A big end of month downward correction is coming, IMO.

[Kentish Man]

No change on Hadley yesterday, despite it being very cold through much of CET land and starting with a hard frost;

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

A big end of month downward correction is coming, IMO.

Yes I agree that is very likely. The Net Weather temp tracker is currently 2.63C as I write this, a drop of 0.2C over the last day or so. The frost barely came out of the ground yesterday. With Manley currently on 1.8C and Hadley on 2.7C a reasonable guess might place the "true" CET after correction at around 2.2C.

[Lettucing Gutted]

Should be fairly interesting how cold the 1st half of December will come in as. Looks like today - 15th will average somewhere around 2.3c. With the current CET at 2.7c, maybe as low as 2.5c by the 15th with low maxima and so the coldest first half of December since 1991 (which averages 2.1c) 

It would be very nice to hear Tamara's thoughts on this remarkable sustained cold spell.

[Matty M]

The Dublin Airport Mean for December 1-10th is 2.5c

Mean Average for December from 61-90 is 5.9c

So running 3.4c below average.

Edited December 11, 2008 by Matty M

[Nick L]

No change on Hadley yesterday, despite it being very cold through much of CET land and starting with a hard frost;

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

A big end of month downward correction is coming, IMO.

Yep. Seems to be rising on slightly less cold days and not budging at all on considerably colder days.

My December average so far is 0.6c, incredible!

Edited December 11, 2008 by nick2702