January 2024 CET and E.W.P. forecast contests

[Midlands Ice Age]

3 hours ago, Methuselah said:

Can't, for the life of me, see what the 'AGW people' having a thread has got to do with this one; this thread simply has data; make of that what you will? 

oh alright then... but it will let us see more of what has happened to the data  in the past. Something not easy to extract from the MO website. 

Do you think a new website would be useful?

 MIA

[Methuselah]

@Midlands Ice Age  I'm really not sure. 

[TillyS]

Big temperature rises this afternoon across central England. It is still 15C in some places at 19h00. Daily maxima are ‘open’ until 21h00 so I’m guessing the CET will see quite a hike.

 

[Roger J Smith]

Yes, CET will go up about 0.3 or 0.4 after a very mild day (9-11), 0.1 or 0.2 after not so mild (7-9). 

About discussion of content of thread, would say, let's just keep doing what we have been doing, the one point I was trying to underscore was to keep chat out of the forecast interval of each new contest thread, so it's good to have the chat in here and not good over in Feb until after 2nd. Don't want to be too rigid, a bit of banter will inevitably occur with the forecasts but I wouldn't want to see technical discussions about February cluttering up the flow of forecasts. If it's in January but discussing February, that's not a bad thing because most readers of this thread will have that next forecast on their mind and can get some ideas from the discussion. 

There is a historical weather section (forum) and one thread in there (presently on page two of menu) is my compilation of CET data analysis (with some EWP analysis added). If you never knew it was there, go take a look some rainy day when you have time to kill. It has all the daily records, warmest and coldest days of every year, rainfall records, heat waves, cold spells, etc. And there are lots of interesting historical weather threads to read over in that forum.

[Roger J Smith]

EWP update _ current value is near 75mm and GFS suggests 20mm grid average (a lot of places lower, but quite wet in n.w. England) to end of January, so an outcome near 95mm.

[WYorksWeather]

As a reminder - 21st-31st required averages:

To finish at 4.0C: 5.7C

To finish at 4.5C: 7.1C

To finish at 5.0C: 8.5C

To finish at 5.5C: 9.9C

To finish at 6.0C: 11.3C

Daily figures, from 21st

7.9, 8.5

Average so far: 8.2C

[Roger J Smith]

Daily CET records 23rd to 31st ...

23 Jan ... 11.6 (1834) 
24 Jan ... 10.6 (1782) 
25 Jan ... 11.6 (2016) 

26 Jan ... 10.0 (1834) 
27 Jan ... 10.5 (2016) 
28 Jan ..... 9.7 (1944,83) 
29 Jan ... 10.2 (1854,1966)
30 Jan ... 10.2 (2000)
31 Jan ... 10.7 (1868)

could see 26 and 28 go, at least. 

 

[WYorksWeather]

@Roger J Smith Today's absolute daily maximum (non-CET) has gone. 15.4C beats 15.2C.

[TillyS]

Double digit minima overnight 

[TillyS]

Temps are now dropping a notch under clearer skies. In fact, looks like it was warmer in the night than it will be in the day for some places. Not that unusual with frontal activity.

26th and 28th do indeed look like vulnerable records this week.

Edited January 24 by TillyS

[TillyS]

3.9C to the 23rd. 

Hadley lists this as 0.0C above the average but I’m assuming that’s because of rounding. The January mean is 3.8C isn’t it?

Met Office Hadley Centre Central England Temperature Data Download

WWW.METOFFICE.GOV.UK

 

Edited January 24 by TillyS

[WYorksWeather]

  @TillyS It's a rounding issue.

In two decimals, the current CET rounds to 3.85 per the Met Office. This must be above 3.850, otherwise it wouldn't round to 3.9 in one decimal. The normal CET to January rounds to 3.81.

Hence, the scenario is likely something like the following. Suppose the normal is 3.805, and the current value is 3.852. The difference between the two is 0.047 if calculated exactly, but when you round off to one decimal place the anomaly is 0.0.

Hope that makes sense!

[damianslaw]

A finish in the high 4s to mid 5s seems a good bet, with an exceptionally mild 21-31st period on the cards. It seems a long time since a notably cold last week to Jan occured, 2017 and 2019 were cold but not especially so, 2013 cold imploded on the 26th, 2010 probably last time, but the cold nowhere on same scale as earlier in the month. 2012 brought the cold in on the 28th I think, 2009 not until 31st. 

[The PIT]

Sunny Sheffield up to 3.8C -0.8C below average. Rainfall 66.6mm 89.5% of the monthly average.

[Roger J Smith]

Two CET daily maximum records have been set so far (not including today, 24th). 

21 Jan 12.5 C broke 1993 record of 12.4 (same in legacy and v2.0).

23 Jan 13.0 C broke 2018 record of 12.7 (CET v2.0) and while it tied 1884 CET legacy, that was reduced to 12.3 C in v2.0. 

I am updating my data base by checking all announced revisions in v2.0.1.0 (from v2.0) and so far I have finished checking daily means, they say 109 of these went up or down 0.1 and one on 23 Dec 1884 (which  was erroneous due to a source document misread) was corrected substantially -- that was way off because one of three locations used (Ross-on-Wye) had a daily max of +5.1 which was entered into CET records as -15.1. (as one third of daily max, it would make that erroneous by +6.7 and thus the daily mean would be +3.4 in error) ... This was noted as a possible error by me in 2020 when I had finished doing an analysis of daily ranges, and I found one where the max was lower than the min (if I had not done that analysis, I would never have suspected the error was there). I reported that plus some EWP errors due to truncation of files, which were also fixed. So anyway, the changes otherwise were relatively unimportant, but did affect two daily records. 15 June 1858 is now 22.7 (was 22.8 in v2.0), and also 3 Dec 1985 is now 12.1 (was 12.0 in v2.0). I am now looking at changes made to daily max and min; there may be fewer because I suspect some of the changes to means are due to changed rounding protocols and the max and min could remain unchanged. But I do expect to find some. If any affect daily records I will note those here. 

[WYorksWeather]

21st-31st required averages:

To finish at 4.0C: 5.7C

To finish at 4.5C: 7.1C

To finish at 5.0C: 8.5C

To finish at 5.5C: 9.9C

To finish at 6.0C: 11.3C

Daily figures, from 21st

7.9, 8.5, 8.6

Average so far: 8.3C

Summary

Still on a knife edge. Hard to see the overall daily average for these last 11 days coming in below 7C or above 10C, so still the 4.5C to 5.5C envelope appears to be the best bet.

[Summer Sun]

4.0c to the 23rd

0.2c above the 61 to 90 average
0.5c below the 81 to 10 average

[johncam]

  @Summer Sun where are thinking it will finish now 

[TillyS]

A finish in the low to mid 5’s looks pretty certain now. 5.2C might be about the landing point.

24 x 4.0C = 96

7 x 9.4C = 66

= 162 / 31 = 5.2C which would be 1.4C above the mean.

Edited January 25 by TillyS

[The PIT]

Sunny Sheffield up to 4C -0.6C below average. Rainfall unchanged.

[WYorksWeather]

21st-31st required averages:

To finish at 4.0C: 5.7C

To finish at 4.5C: 7.1C

To finish at 5.0C: 8.5C

To finish at 5.5C: 9.9C

To finish at 6.0C: 11.3C

Daily figures, from 21st

7.9, 8.5, 8.8, 8.4

Average so far: 8.4C

Summary

I think a couple of days will achieve 10C averages, but some closer to 8C, so a probable average for the 21st-31st of around 9C would be my guess, leading to a finish in the low 5s.

[Metwatch]

EWP is up to 80mm to the 23rd.

It looks to stay quite dry for the rest of the month, with the exception of North west England and Wales. So a final value of around 90mm to end this month?

 

Looking at the entries I think @Don and @moorlander  are looking to be the closest combined, but will depend on where the CET will make it. I still think 5.0 looks to be the highest possible value now, 5.1C if i'm really pushing it. Most confidence is in the 4.8 - 5.0C area. Although doesn't look to be bang on, I'm fairly happy with my entry as well.

Edited January 25 by Metwatch

[Don]

  @Metwatch Yes, it would be nice to be close for a change!

[Summer Sun]

4.2c to the 24th

0.4c above the 61 to 90 average
0.3c below the 81 to 10 average

[damianslaw]

A week to go, and with alot of very mild weather forecast, a probable finish in the 5s could now verify, somewhere in the 5-5.5 range, the above average months continue.