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. 

For those taking part in the competition all CET predictions for both January and for 2021 as a whole should be sent directly to me via the forum private message system. Do not post them directly into the thread. 

Historic CET summary for January 

1981-2010 4.4C (30 years)  

1991-2020 4.7C (30 years)  

2001-2020 4.7C (last 20 years)  

Last January was very warm with a CET of 6.4C. The previous year was slightly below average at 4.0C. The last very cold January was 2010 with 1.4C. Could we challenge that this year?  

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

Direct link to larger version of the chart

Current model output   

First half of January looks cold. Lots of scatter by mid-month but that is quite normal at that range. General prognosis is cold for the foreseeable future.

GFS 850s 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=5&run=6&lid=ENS&bw=

ECM looks to be similar to GFS - i.e. cold. 

ECM ENS 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/3moutlook-jfm-v1.pdf

Probabilities favour something slightly above average for January. But the likelihood of a cold January is higher than in recent years. Precipitation  outlook is close to the mean - very slightly above average.

Here is a first look at the January CET tracker

Chart1

Chart2

I've gone cold but not excessively so. Had I gone for a crazy low CET the weather Gods would have seen to an exceptionally mild January because that's how the weather works in this country 😉

Liking the lack of comment on that CET tracker .

This certainly is a tricky start to the year for the competitors, with a cold pattern already in place prior to expected influence from a sudden stratospheric warming that will either sustain/intensify the cold setup or cause it to shift away from us.

It's snowing here (Leyland) as I put my entry in....

If so I will send my prediction in.

Yes. It is absolutely fine to send in predictions during the course of today.

Thanks!

PM just sent in and it's quite a month to predict No good just going for average plus a degree or so this month that's for sure. I imagine there will be quite a spread of predictions and I look forward to seeing what they are. I wonder if anyone will go for a sub-zero month? Unliikely of course but not completely beyond the bounds of possibilty.

Happy New Year everyone. Thanks everyone for your lovely comments and for joining the 2021 competition. We have just over 40 entries so far. If anyone would still like to join I will give you until the end of today to send me a PM.

Also if you have not yet made a prediction for the 2021 annual CET and would like to do so, I will keep this open for another couple of days.

Here are the predictions for January. A nice spread to start the year.

Chart 1

Met Office Hadley       0.5c.      Anomaly     -3.0c Provisional to 1st.

Metcheck                    1.23c     Anomaly     -2.92c

Netweather                 1.77c     Anomaly     -2.44c

Peasedown St John    1.4c       Anomaly     -3.5c.  

I've been led astray by cold looking output at the start of winter months that have then gone on to be average to mild too many times to trust this one not to flip in the second half!

And I'm surprised I'm so low down with 2.31C. I thought I was steering something of a middle course there, acknowledging the forecasts/models being cold for the reliable timeframe yet not getting away with the idea it would be a bitterly cold month.

I turned it around though to 3.2c and I’m not sure that was wise!  So good luck Col!  

Met Office Hadley       0.5c        Anomaly       -3.0c Provisional to 2nd

Metcheck                    1.14c      Anomaly       -3.01c

Netweather                 1.63c      Anomaly       -2.58c

Peasedown St John    1.27c      Anomaly       -3.69c.     

Here is the final prediction table for January plus the annual CET predictions. For the latter I had to make a couple of minor changes to the later predictions where there was a duplication, so we have a unique winner when we get to the end of the year. There are a number of very similar predictions in the high 10.6's

Table 1

Table 2

Ah crud, I forgot about the annual CET.

Met Office Hadley     1.0c     Anomaly       -2.4c provisional to 3rd.

Metcheck                  1.56c   Anomaly       -2.57c

Netweather               2.06c   Anomaly       -2.15c

Peasedown St John   1.5c    Anomaly       -3.4c.   

Given latest model output, I think your 3.2c will be nearer the mark than 2.3c

I'm fairly content with my 3.6c at this stage.

We shall see, it's only day 4 and I'm not panicking yet. The second half of the month is still up for grabs and there is always the 'wildcard' of the SSW towards the end of the month to consider. As long as I can 'bank' some reasonable cold during the first half, dull & dreary days of 3/4C and temps a little below freezing would be fine to offset somewhat milder weather later.

If you're closer to the mark than me, I won't be complaining 

Met Office Hadley        1.5c      Anomaly      -1.9c Provisional to 4th

Metcheck                      1.76c   Anomaly      -2.40c

Netweather                   2.38c   Anomaly      -1.83c

Peasedown St John     1.8c     Anomaly      -3.1c