C.E.T. forecasts for December 2015 (start of 2015-16 competition year)

[Timmytour]

1 hour ago, Nick L said:

We've long run out of superlatives to describe this spell I think.

The ones that can be used in polite company anyway.....I've still a few choice words that I could use!  

[Timmytour]

Absolutely no question that this December will register a mean CET of greater than 4C and in the process run up the seventh successive winter month that does so.

Perhaps we were due such a run......  previous runs of seven successive winter months were racked up in 1919-21, 1947-49, 1972-74, 1987-89, 1997-99 and 2003-05.

Unfortunately....the last five of these runs all went on to register an 8th successive month as well!  Maybe a little pointer for any January guesses

 

[Scorcher]

3 hours ago, summer blizzard said:

Agreed. I found March 2012 almost pornographic in terms of how perfect it was (maxima around 20C, stupid amounts of sunshine, no humidity) but it really highlights the difference between a large durinal range and the current cloudfest we have now.

The amazing thing about that month was that it could have been even warmer- we missed out on an earlier warm spell which originally looked like it could be record breaking, due to fog. I recall the near Continent had some very high temperatures during that period.

[Weather-history]

The difference between 26th November-27th December 2010 and 26th November-27th December 2015 is going to be huge.

26/11/10-27/11/10: -1.5C

26/11/15-27/11/15: ?

[Captain Shortwave]

One thing I have noticed with regards to the models is this which I thought is absolutely staggering.

Most of Southern England and the Midlands will not see single figure temperatures for the next 5 days (including nights with temperatures remaining in double figures until Sunday night when we finally see some cooler air move in).

[Weather-history]

7 hours ago, Relativistic Sting Jet said:

Take a look at 1795 and 1796.

1795 was the coldest January (and month) on the CET record, at -3.1C.

A year later in 1796, January recorded a CET of 7.3C.

That's a range of 10.4C! In a year!

Edit:
At the time, January 1796 was the warmest January on the CET record, and it still stands at joint second with 1921. So in the space of a year the warmest and coldest January's on record were recorded. Staggering really.

They say our weather is beginning to swing from one extreme to the other, but it's happened all before!

Anyway, to keep this on topic, to beat this remarkable swing December 2015 would have to record a CET of 9.8C or higher. A tall order.

There is something even more remarkable, 1796 started exceptionally mild and  ended exceptionally cold.  Mildest January at the time and ended with the second coldest December.

[Scorcher]

 

2 hours ago, Weather-history said:

The difference between 26th November-27th December 2010 and 26th November-27th December 2015 is going to be huge.

26/11/10-27/11/10: -1.5C

26/11/15-27/11/15: ?

I think if you take off the minus and put a zero between the 1 and the decimal point, you might not be far off.

[Roger J Smith]

Speaking of that temperature gradient, over in Ireland the mean so far at Shannon is 9.4 C but only 6.5 C at Markree in Sligo. There was snow in parts of the north on Saturday and a low of -3.1 at Markree on Sunday morning. Otherwise, the gradient in Ireland has been running about 1-2 degrees all month (which is normal) but it was closer to seven degrees on Saturday and the minimum on Sunday. I imagine it's similar for Northern Ireland, a lot of the apparent gradient can be explained by the weekend storm track.

Meanwhile, current GFS 12z output for 25th to 31st indicates a highly variable pattern with an interruption in the record warmth now timed for 26th-27th and the 31st looking rather cold too. Other days would be in the 8 to 10 range (at least). So estimating 6.5 as a mean for the seven days which gives an outcome of 9.0 before corrections. I'm pretty much ready to throw in the towel but I think it's still more likely than not that Craig's 9.0 will be high rather than low (not that it matters much).

Edited December 15, 2015 by Roger J Smith

[Peter H]

If this keeps up until the end of the month and there's no reason why it shouldn't according to the models, then something above 9.0 is surely a possibility.

What's the record high CET for December ?

[jvenge]

2 hours ago, Peter H said:

If this keeps up until the end of the month and there's no reason why it shouldn't according to the models, then something above 9.0 is surely a possibility.

What's the record high CET for December ?

8.1 from 1934 and 1974.

It's looking highly likely that it will be broken.

[Summer Sun]

9.2c to the 15th

4.3c above the 61 to 90 average

4.2c above the 81 to 10 average

Provisional joint daily high last set in 1898

[BornFromTheVoid]

Minimum today is 9.0C, while maxima look like hitting the mid 13s, so an increase to 9.3C is likely on tomorrows update.

After that, the 06z GFS has the CET at:

9.5C to the 17th (12.9: +8.5) [Record High: 11.6C]
9.7C to the 18th (12.1: +7.7) [Record High: 11.8C]
9.8C to the 19th (12.9: +8.6) [Record High: 11.6C]
9.9C to the 20th (11.9: +8.2) [Record High: 11.1C]
10.0C to the 21st (10.4: +6.2) [Record High: 11.4C]
10.0C to the 22nd (10.0: +5.5)
9.9C to the 23rd (8.6: +3.9)
9.8C to the 24th (7.8: +3.1)
9.8C to the 25th (8.6: +4.1)

A record mild month all but certain now, with the main question being whether we can stay above 9C or not.
The record daily average for the 16th is is 10.8C, so after a min of 9.0C we only need a max today of 12.6C to set a new record, so that's pretty much a given. A good chance of setting 5 consecutive daily records from today through to the 20th. Also, to get into the top 10 most +ve daily anomalies, at least +8.6C is required, something we might also achieve over the next few days.

[kev238]

Quite incredible statistics 

this month looks likely to be warmer than november though a cool down below 9 can't be ruled out as yet! 

[The PIT]

Sunny Sheffield back up to 7.8C pretty sure it will be 8c by the end of tomorrow. Pretty sure  unless models suddenly flip tomorrow we'll get a new record.

[Roger J Smith]

If there were five daily warm records consecutively, it would be a new record, oddly thanks in part to the record set on 1st July 2015. That terminated the former record of seven days 28 June to 4 July 1976 and left two three-day intervals which joined quite a few others in a list that I made in the historical CET thread:

https://forum.netweather.tv/topic/73431-daily-cet-average-values-1772-2011/?page=2

The record now anyway is the four day heat wave 28-31 July 1948. so that five days would represent a new record. There were six consecutive cold records at the end of January 1776 so it won't be a record in the absolute sense.

In that list, the only other December spell of three consecutive warm records was 27-29 Dec 1987. There have been three occasions with three consecutive cold records, in 1798, 1859, and 2010. The most recent spell of three consecutive warm records in any month was 28-30 Sep 2011. That also went five for six by 3 October with its most prolific day (1 Oct) being edged out by 1 Oct 1985. One of the records that is under threat in this five-day period was set last year, 11.8 on 18th Dec.

Edited December 16, 2015 by Roger J Smith

[Weather26]

 

3 hours ago, Roger J Smith said:

If there were five daily warm records consecutively, it would be a new record, oddly thanks in part to the record set on 1st July 2015. That terminated the former record of seven days 28 June to 4 July 1976 and left two three-day intervals which joined quite a few others in a list that I made in the historical CET thread:

https://forum.netweather.tv/topic/73431-daily-cet-average-values-1772-2011/?page=2

The record now anyway is the four day heat wave 28-31 July 1948. so that five days would represent a new record. There were six consecutive cold records at the end of January 1776 so it won't be a record in the absolute sense.

In that list, the only other December spell of three consecutive warm records was 27-29 Dec 1987. There have been three occasions with three consecutive cold records, in 1798, 1859, and 2010. The most recent spell of three consecutive warm records in any month was 28-30 Sep 2011. That also went five for six by 3 October with its most prolific day (1 Oct) being edged out by 1 Oct 1985. One of the records that is under threat in this five-day period was set last year, 11.8 on 18th Dec.

As you said 2 days ago it would be utterly hilarious if we get a white Christmas out of a very barmy month however unlikely this is beginning to sound.

[AderynCoch]

On 15/12/2015 at 8:18 AM, Nick L said:

Yes to say that Dec 2010 never looked likely to break the record is untrue. If it wasn't for that milder final few days it would have broken the record comfortably.

December 2015 is the anti-Christ to December 2010.

But those milder final few days were forecast some days in advance, so even with the cold we were having it still didn't look quite cold enough to break the record. We did of course get within 0.1C but only after a large downward correction. My point was that this time round we already knew the record was gone before we'd even reached the half-way point, partly due to the stupidly mild temperatures we've had to endure but also due to how much confidence there is that the pattern won't break before month's end. This never happens with cold spells: even when they do stick around there's always doubt in FI (maybe the models just aren't used to cold blocking and revert to Atlantic westerlies by default), and I'd venture that even 62/63 would never have been nailed-on to last that long with modern forecasting technology.

Try to imagine a December running at -2C mid-month with a bunch of -10C days forecast and a strong consensus for no change in the weather pattern and then you have something resembling the chalk to this month's cheese.

[Harve]

http://www.met.reading.ac.uk/~brugge/CURR.html

 

There are places on the south coast of England which are averaging 11c minimums so far this month? That's outrageous. I spent the first 18 years of my life in Derbyshire, granted at a high altitude, and hitting a 10c maximum just once in a winter month would be noteworthy. 

 

(The quote system seems to be bugged since the forum upgrade and I can't delete below without deleting my entire cache. Are there plans to change this?)

9 hours ago, BornFromTheVoid said:

9.8C to the 24th (7.8: +3.1)

[Weather-history]

To think we have lived through the 2nd coldest December on record and probably the mildest December on record.

I lived through February 1986 and 1990 and later 1998 and that was a 8.4C contrast. This will be even larger if December record falls, at least 8.9C if correct.

It could beat the February 1947/February 1990/98 contrast, January 1963/2007 contrast. They are the largest contrasts that anyone alive now could have lived through but there is a large interval between the two.

December 2010 and 2015 is only 5 years.

[North-Easterly Blast]

Of particular note is the fact that although December 2010 finished as the 2nd coldest on record, the cold had abated on the 27th / 28th, and the final four days were close to average.  From the 27th Nov - 27th Dec 2010; that period averaged -1.5*C, a full 0.7 colder than the all time December record.  This makes 2010 the coldest month's run up to Christmas since at least 1772. 

It now looks very likely when the figures are in, only five years later, this has swung to completely the opposite extreme, and we could well see the warmest month's run up to Christmas since at least 1772, and a similar period of dates to in 2010 being the warmest on record, in complete reversal to 2010, and very likely a 10*C+ difference between the two monthly periods.  So pre Xmas 2015 will almost certainly turn into the "evil twin" of pre Xmas 2010.

 

Edited December 17, 2015 by North-Easterly Blast

[Snowyowl9]

13c last night.

[Scorcher]

Even less signs of a cool down this morning from the op runs. Less week is looking less exceptionally mild than this week but still well above average with SW winds dominating if the ECM is to be believed. It says it all when the BBC are saying Friday is going to be a 'fresher' day with maxes still in double figures for most of the country!

This really is one of the most remarkable months of our time- up there with April 2011 in my view.

[Scorcher]

10 hours ago, Harve said:

http://www.met.reading.ac.uk/~brugge/CURR.html

 

There are places on the south coast of England which are averaging 11c minimums so far this month? That's outrageous. I spent the first 18 years of my life in Derbyshire, granted at a high altitude, and hitting a 10c maximum just once in a winter month would be noteworthy. 

 

(The quote system seems to be bugged since the forum upgrade and I can't delete below without deleting my entire cache. Are there plans to change this?)

Well to put that in perspective, it was 14C at Manchester Airport at 1 am. I'm pretty sure it would have been above 10C even at altitude in Derbyshire at the same time too.

[Summer Sun]

9.3c to the 16th

4.4c above the 61 to 90 average

4.3c above the 81 to 10 average

Provisional daily record

Edited December 17, 2015 by Summer Sun

[Man With Beard]

3 hours ago, Thunderbolt_ said:

I think every other mild winter month (you can even more or less add every mild November and March to that too) is going to look pretty puny once December 2015 has finished with us..

Yes indeed I was only just thinking, the December record is about 80% likely to go, but there's a very very small chance of getting close to the November record too, given some of the ensemble output I've seen!