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Global Warming
30 December 2019 19:40:15

This thread is for all comments, discussion and analysis of temperatures in the UK during January, with particular emphasis on the Central England Temperature (CET), for the simple reason that it is the longest running temperature series in the world with over 360 years of data. But you can comment on any interesting temperature statistics or data from across the UK, including your own back yard. 


To make things a little more fun we also run a competition in this thread throughout the year. This is by no means the only focus of the thread and you don't need to participate in the competition to post here. But it is a bit of fun which many of us enjoy. 


The competition is run on a monthly basis and you can participate in just one or two or all of the months. For those who do take part throughout the year there is an annual competition which runs alongside the monthly competition. Full details are set out below. There are no changes from previous years so those familiar with the competition do not need to read through everything. I have decided it is just too time consuming to add any additional elements to the way in which the competition works.


For those taking part in the competition all CET predictions for January should be sent directly to me via the forum private message system. Do not post them directly into the thread.


You can also send me predictions for the average CET for 2020 as a whole if you wish along with your January prediction.


The deadline for predictions this month is 2359 on Wednesday evening (1 January). Normally the deadline is the last day of the month but given it is New Year's Eve most people will be otherwise engaged. So for this month only the deadline is extended by 24 hours.


To keep things simple there will be no late submission penalty system as such going forward (I haven't actually applied any penalties for the past couple of years). The hard deadline for submissions will be the second of the month every month but you can make your prediction at any time before that. You can adjust your prediction once only each month prior to the deadline. Entries after 2359 on the final day of the month (January excepted) will only be accepted at my discretion if I consider there is a reasonable excuse.


Here is a reminder of how the CET competitions work for the benefit of everyone but also anyone who would like to join in for the first time. All are welcome to participate.


How do the competitions work?


Each month a new thread is opened a few days in advance of the start of a new month. Your challenge is to predict the mean Central England Temperature (CET) for the following month. The CET is the longest running temperature series and goes back to the mid 1600's. Each month I post some statistics about the CET for that month in recent years as well as a summary of some of the latest model output and long range forecasts to provide some context to assist you in making your prediction. 


Predictions can be made either to one or two decimals (the actual data is published to two decimals). The closest person or persons to the final figure at the end of the month are declared the winner for that month. There are no prizes. This competition is just a bit of fun and the chance to amaze your fellow posters with your skill and foresight in predicting the weather (or you can just make a random guess!).


We use the Hadley data for the purposes of this competition which is maintained by the Met Office. Provisional figures are published daily with a final adjusted number usually issued on the first day of the following month.


In addition to the monthly competition there is an annual competition which runs throughout the year. The annual competition keeps a running total of the cumulative prediction errors from each month for each person. Absolute differences are used so it makes no difference if you overpredict or underpredict the CET in any given month. At the end of the year the person with the lowest cumulative prediction error after totalling each of the 12 months is declared the winner for the year. This is always a hard fought contest and requires a consistency of good predictions in order to win.


Summary of important points 


- Predictions can be made up to 23:59 on the final day of the month before the one to which the prediction relates. No entries will generally be accepted after this time unless I am late in opening up the thread. 


- All predictions should be made by private message to me. 


- Once you have sent your prediction you are only permitted to change it once prior to the deadline. Any subsequent amendments will be ignored.  


- You may make a prediction to either one or two decimals. You can predict the same figure as someone else.


- Where two members have the same cumulative prediction error for the year at the end of any month, the order of ranking in the competition table will be determined by which person has had the closest prediction to the actual CET in any month. If there is a still a tie I then look to the second closest prediction for each person and so on until the tie is broken. If the tie cannot be broken (very unlikely by December but can happen in the first couple of months of the year) then each person impacted is awarded the same position in the table. 


Missed predictions


If a person participating in the annual CET competition does not make a prediction in any one month (including January) their prediction error for that month will be calculated as follows:


- the upper quartile (75th percentile) of the prediction errors of all the people in the annual competition who did make a prediction for that month will be calculated at the end of the month; 


The result of the above calculation will be used as the CET prediction error for any person who misses a prediction in a particular month subject to one further point:


- If, for any person, their average monthly prediction error for all the previous months in the year to date is higher than the 75th percentile of errors (for those that did make a prediction) in the month the person in question made no prediction, then the average prediction error will be substituted instead of the 75th percentile figure. This override is only likely to apply to those people towards the foot of the table who have very made very large errors in previous months. 


One final important point. If you want to be included in the year long competition you may not miss more than two predictions during a calendar year. If a third prediction is missed that person will be eliminated from the annual competition (otherwise it would mean 25% or more of the annual error being calculated on non-existent predictions which would reduce the credibility of the competition too much). However, that person can continue to make predictions for the purpose of the monthly competition.


Now on to some data for January:


Historic CET summary for January


1971-2000 4.2C (30 years)


1981-2010 4.4C (30 years) 


1999-2018 4.6C (last 20 years)


We have not had a cold January since 2013 and that was only 0.7C below the 1971-2000 mean. There have been three years above 5C recently - 2014, 2016 and 2018. Last very cold January was 2010 with 1.4C. 


Here is a chart of the January CET for all years since 1961:


Direct link to larger version of the chart CHART


UserPostedImage


Current model output (at 12z 30 Dec)


GFS 850's -https://www.wetterzentrale.de/de/show_diagrams.php?model=gfs&var=2&geoid=49069&lid=ENS&bw=


GFS T2m - https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gfs&var=202&run=12&lid=ENS&bw=


ECM ENS T2m -http://cdn.knmi.nl/knmi/map/page/weer/waarschuwingen_verwachtingen/ensemble/detail/ensemble-verwachtingen-detail10.png


Met Office contingency planners outlook 


https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-jfm-v1.pdf


First look at January temperature tracker


Coming soon

ARTzeman
30 December 2019 22:55:57

Happy Predictions Folks. Mine is in but never get anywhere except near the bottom. Enjoy posting on the tread. 






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
Caz
  • Caz
  • Advanced Member
31 December 2019 05:20:34

Mine’s in!  


Good luck for the new year everyone. Here’s hoping all your predictions are good ones! But more importantly, just enjoy the ride!  


Market Warsop, North Nottinghamshire.
Join the fun and banter of the monthly CET competition.
SJV
  • SJV
  • Guest Topic Starter
31 December 2019 13:11:07
Good luck and Happy New Year to all!

I'm looking forward to fully participating in this years CET competition. My prediction is in 😁
Col
  • Col
  • Advanced Member
31 December 2019 13:40:04


Mine’s in!  


Good luck for the new year everyone. Here’s hoping all your predictions are good ones! But more importantly, just enjoy the ride!  


Originally Posted by: Caz 


Enjoy the ride? Well I certainly did that this year that's for sure! Unfortunately it ended up with me going far too low for December and doing a good 'Devon Loch' impression with regards to this years competition!


But onwards and upwards.... My prediction is in and unlike the last few months noboby will really care what it is 🙂 Glad to see the format hasn't changed. Some people were proposing various complications to the scoring system but it's good that it's being kept simple.


 


Col
Bolton, Lancashire
160m asl
Snow videos:
http://www.youtube.com/channel/UC3QvmL4UWBmHFMKWiwYm_gg
Windy Willow
31 December 2019 14:47:51

Good luck everyone! & Happy New Year!!


South Holland, Lincs 5m/16ft ASL

Don't feed the Trolls!! When starved of attention they return to their dark caves or the dark recesses of bridges and will turn back to stone, silent again!
Caz
  • Caz
  • Advanced Member
31 December 2019 16:46:40


Enjoy the ride? Well I certainly did that this year that's for sure! Unfortunately it ended up with me going far too low for December and doing a good 'Devon Loch' impression with regards to this years competition!


But onwards and upwards.... My prediction is in and unlike the last few months noboby will really care what it is 🙂 Glad to see the format hasn't changed. Some people were proposing various complications to the scoring system but it's good that it's being kept simple.


Originally Posted by: Col 

I think, letting someone else win is very noble of you Col!  
Seriously, you’ve had a brilliant run throughout the year!  Well done and good luck for the coming year!   


Market Warsop, North Nottinghamshire.
Join the fun and banter of the monthly CET competition.
Stormchaser
31 December 2019 20:52:23

Continued thanks for maintaining this competition, GW .


Best wishes to you and everyone else here for 2020; Happy New Year when it hits!


 


Looks to be getting off to a very tricky start, to make things interesting. The exact amount of influence from high pressure versus Atlantic lows throwing warm sectors our way will make a vast difference to the surface temps.


Estimates to 9th from recent GFS runs, to illustrate the huge range of possibilities:


12z of 29th: 3.6*C
06z of 30th: 6.7*C
12z of 30th: 5.4*C
00z of 31st: 3.6*C
12z of 31st: 6.9*C

That's 3.3*C of spread for just the first 9 days!


Could this be the most uncertain CET month we've ever taken on? 


If you have any problems or queries relating to TWO you can Email [email protected]

https://twitter.com/peacockreports 
2023's Homeland Extremes:
T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On
ARTzeman
01 January 2020 11:17:46

Day ONE.   Metcheck on 4.91c 


Peasedown presently on 5.9c.   






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
ARTzeman
02 January 2020 10:50:33

Met Office Hadley         5.8c        Anomaly       2.3c   Provisional to 1st.


Metcheck                      5.49c      Anomaly       1.33c


Netweather                   5.74c      Anomaly       1.55c


Peasedown  St John   6.75c     Anomaly    1.47c                          






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
ARTzeman
03 January 2020 10:48:28

Met Office Hadley         6.7c.        Anomaly      3.1c.  Provisional to 2nd.


Metcheck                      6.86c        Anomaly       2.70c


Netweather                   7.18c        Anomaly       2.99c


Peasedown St John     7.9c       Anomaly          2.62c.  






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
ARTzeman
04 January 2020 10:55:51

Met Office Hadley             6.7c       Anomaly       3.3c Provisional to 3rd.


Metcheck                          6.58c     Anomaly       2.43c


Netweather                       7.27c     Anomaly       3.08c


Peasedown St John         7.5c        Anomaly        2.22c.






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
ARTzeman
05 January 2020 11:07:24

Met Office Hadley           6.6c       Anomaly        3.2c. Provisional to 4th.


Metcheck                        6.60c     Anomaly        2.45c


Netweather                     7.15c     Anomaly        2.96c


Peasedown St John        7.4c       Anomaly         2.12c. 






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
Global Warming
05 January 2020 12:03:45

Here is the latest January CET tracker. Absolutely crazy figures here. We could well start off the new decade by breaking the all time January CET record which stands at 7.5C and was set in 1916. 


Latest tracker has us at 7.6C by the 18th. I have added in 1916 for comparison. That year started exceptionally mild and settled into the mid 7s by the end of the second week. We have started cooler this year (but still well above average) and should be into the mid 7s later this week, potentially holding fairly steady after that.


The wild card is the final week of the month. Some of the model output has been hinting at colder conditions being a possibility. But I would not bank on that. It will be difficult to dislodge the strong zonal flow we have at the moment. The long range models before the start of the winter mostly went for very mild conditions and have been proved right so far. Personally I think that will continue for the foreseeable.


We could well find that March is colder than December, January or February. The December QBO figure is in and it has fallen to just +1.66. So still westerly but likely to turn easterly during January. There is usually something of a lag before that switch starts to have a real impact. Hence why I think March could be the coldest month of the of the winter / early spring period. The QBO should be more favourable next winter. It often takes around 10-12 months to reach the lowest point in the easterly phase. So if January 2020 is the first easterly month the peak of the easterly flow may well be around the end of this year as we go into next winter.


https://www.esrl.noaa.gov/psd/data/correlation/qbo.data


My CET prediction calls for the January record to be broken.


UserPostedImage


CHART1


UserPostedImage


CHART2

Global Warming
05 January 2020 12:38:20

Here are the January predictions. We have 35 entries. Everyone has gone above average.


UserPostedImage


TABLE

Col
  • Col
  • Advanced Member
05 January 2020 12:49:04


Here are the January predictions. We have 35 entries. Everyone has gone above average.


UserPostedImage


TABLE


Originally Posted by: Global Warming 


Normally I would have said you'd really stuck your neck out with that prediction, but not this month.


Correctly calling a new monthly CET record would be no mean feat.


Col
Bolton, Lancashire
160m asl
Snow videos:
http://www.youtube.com/channel/UC3QvmL4UWBmHFMKWiwYm_gg
Spring Sun Winter Dread
05 January 2020 15:23:24
I certainly think I've gone too low and after the December we had in 2015, that January record of 7.5c looks like one which is inevitably destined for a tumble - and possibly by some margin- at some point with this year now looking not out of the question. February's 7.9c will also be smashed out of the park at some point I'm sure, it would have been last year were it not for the snow at the beginning and lack of mild cloudy nights.
Kind of depressing from a weather watching perspective but I'll take the lower heating bills!
Whether Idle
05 January 2020 15:29:17

I certainly think I've gone too low and after the December we had in 2015, that January record of 7.5c looks like one which is inevitably destined for a tumble - and possibly by some margin- at some point with this year now looking not out of the question. February's 7.9c will also be smashed out of the park at some point I'm sure, it would have been last year were it not for the snow at the beginning and lack of mild cloudy nights.
Kind of depressing from a weather watching perspective but I'll take the lower heating bills!

Originally Posted by: Spring Sun Winter Dread 


I wouldn’t be so sure. I’m expecting the first it 20 days to be broadly mild. But then I’m expecting a cooler final third, possibly cold at times. Hold your nerve soldier. 


Dover, 5m asl. Half a mile from the south coast.
Spring Sun Winter Dread
05 January 2020 18:00:33
It's true. However much of a weather expert you are and however hard you study the models, I can't help but think the last third of a month is basically a guessing game at the start of it
Caz
  • Caz
  • Advanced Member
05 January 2020 18:21:00

I’m certainly thinking I’ve gone too low with 5.2c!  


Market Warsop, North Nottinghamshire.
Join the fun and banter of the monthly CET competition.
GezM
  • GezM
  • Advanced Member
06 January 2020 11:12:42


I’m certainly thinking I’ve gone too low with 5.2c!  


Originally Posted by: Caz 


I foolishly put some faith in the Met Office 4 week outlook which has consistently forecast temperatures returning to nearer normal, possibly cold at times. So I was expecting a dip later in the month. Could still happen I suppose but now looking unlikely.


Living in St Albans, Herts (116m asl)
Working at Luton Airport, Beds (160m asl)
Stormchaser
06 January 2020 11:14:51

Wow GW, I'm impressed by your bravado!


I was seriously deliberating a very high estimate for this month, seeing that so much is in place for that, but kept getting this nasty feeling that if I did so, high pressure would manage to build just about far north enough to produce some cold inversion weather at times.


The risk of that increases as the month goes on, due to the seasonal vortex easing aided by the QBO turning more and more easterly.


 


So, I cowardly backed out of anything much more than a degree above the LTA. Let's see how much I regret it now, having told you what I might have done .


 



Liking your thinking regarding odds of March being the lowest-CET month. We really do need to see some good releases of cold air from the Arctic to reduce the snow cover deficits across the mid-latitudes in general, else the spring heat-up is going to be rampant with so little to oppose it.


If you have any problems or queries relating to TWO you can Email [email protected]

https://twitter.com/peacockreports 
2023's Homeland Extremes:
T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On
ARTzeman
06 January 2020 11:20:51

Met Office Hadley          6.7c.       Anomaly     3.2c Provisional to 6th


Metcheck                      6.74c        Anomaly    2.59c


Netweather                   7.25c        Anomaly    3.06c


Peasedown St John      7.5c       Anomaly        2.22c   






Some people walk in the rain.
Others just get wet.
I Just Blow my horn or trumpet
Bolty
06 January 2020 12:31:29
So January running higher than both November and December so far, and there's not much sign of any significant drop in that figure for the forseeable either. It would be incedible if January turned out to be the warmest month of the extended winter (November to March included). I wonder when the last time that happened was, if ever?
Scott
Blackrod, Lancashire (4 miles south of Chorley) at 156m asl.
My weather station 
Spring Sun Winter Dread
06 January 2020 13:51:00
In 1916 it was by some margin. Both November and March surrounding that winter were exceptionally cold. Must have been a very strange winter and nature must have got very confused

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