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

[Don]

 Metwatch I was 0.2C too high, but all good and glad it came in below my guess, rather than above!

[Dancerwithwings]

0.1c out is my best January guess yet since the competition started

In January my hearsay coldie heart seems to rule my head and my January guesses always tend to be around a whole 2c out…..but not this year  

[damianslaw]

An above average month, but not by much using more recent means, indeed very average taking the last 30 years, showing how mild many Januaries have been.

We did experience a decent cold 2 week period at least 6-20 Jan, with three ice days. Annoying that mild sector on the 16th! Certainly many a poorer Jan on the cold front from a Windermere perspective, aware for many it was a snowless month and no appreciable cold. 

Edited February 1 by damianslaw

[Frigid]

Not as mild as I expected, certainly looked like mid 5s a week ago. Same CET as 2022, and I suspect a similar sunshine amount too. Can only recall around 3-4 deluge days, mostly dry.

So an average January, quite challenging to get anything close to average these days. Though if the last 10 days were just average, the CET would've been much lower. 

[TheOgre]

Bog standard January by the looks of it by temperature and rainfall. A frosty spell, a mild spell and everything in between. Very similar to last year.

[Dancerwithwings]

 TheOgre 

“A frosty spell” ….The CET widely had lows of - 7c to - 10c 

Thats hardly bog standard

Edited February 1 by Dancerwithwings

[The PIT]

Sunny Sheffield finished at 4.7C +0.3C. Rainfall 77.2mm 103.8% of the monthly average. 43mm of that fell in the first three days.

[Summer8906]

 Metwatch Interesting it's average for 91-20, though that would obviously mean it's slightly mild by my chosen 30-year-period 1981-2010 (I choose that as it represents the majority of my earlier weather memories, which date from 1978, so is a good point of reference for personal experience).

Went rather too high myself, I was expecting a more prolonged mild wet spell with only shorter colder interludes, though I was expecting the coldest weather at the end of the month!

It does seem the January part of the mild spell was overcooked, I guess we'll see with the February part.

Still no particularly early flowering down here either, confirming it hasn't been as mild as all that. Earlier than some years, but nothing notable. For example, few crocuses out yet.

I wonder if the south was colder relative to normal, rather like 2017 and 2022? The mildness towards the end seemed more pronounced in the north, and I get the impression (I was away) that the cold spell showed a stronger deviation from the norm in the south.

"Boring" would be a good description for most of the 21st-31st, though! Very dull through the latter part of the month, aside from the 26th and to some extent the 27th and 28th.

I guess two short very wet spells (1st-4th and 21st-25th) may make it slightly wetter than average but it breaks the long sequence (since 1974) of Januaries featuring prolonged wet spells in years ending in 4.

Would be interesting to see the rainfall and sunshine figures. Guessing average sunshine with frequent sunny weather during the cold period balanced out by a dull start and long dull spell at the end?

Edited February 1 by Summer8906

[damianslaw]

 Summer8906 Not sure about the south being colder relative to average, more a case of the north being so especially the 2 week period 6-20th which went a bit unnoticed I feel. There were a handful of very mild days at the very start and in the latter part of the month but not prolonged. 

[Roger J Smith]

I edited table back in the thread for top CET averages 21st to 31st, turned out 2024 finished in 9th place (out of 253). The odd part of Jan 2024 was that three intervals were (1-5, 6-20 and 21-31) either well above or well below the overall average and there was no day within 0.5 of the outcome. It's quite unusual to see such a distribution. 

[damianslaw]

 Roger J Smith Didn't Dec 2022 do something of the same, though I suspect the 1-7th was close to average, but the 8-18 well below and 19-31 well above. 

[Roger J Smith]

It was very similar except there were several days in part one (1st, 4th, 6th) that were close to the average for Dec 2022, as it worked out the intervals were:

Dec 2022 ___________ Jan 2024

1-6 average 4.2 _____ 1-6 avg 6.6, (1-5 avg 7.2)

7-17 average -1.6____ 7-20 avg 1.4 (6-20 avg 1.7)

18-31 average 7.2 ___ 21-31 avg 7.6

Dec 2022 avg 3.2 ____ Jan 2024 avg 4.7

so I guess we'll have to see if Feb 2025 works out like this also to create a 13-month cycle.

[Roger J Smith]

EWP tracker finished on 96.6 mm. Only a small amount was added for rain across northern regions on 31st, however, I will just wait now until table value on 5 Feb is made known, as it could be different again. For now I will leave EWP scoring and ranks unadjusted but they would need a bit of work if final value is in range of 95 to 101. If final is 101 to 103 probably as is with slight edits. 

So check back on 5 Feb to find out EWP final scoring. If value is close to tracker 96.6 mm, dancerwithwings would take first place for January and do even better in the "best combined" with a second CET and first EWP. 

[damianslaw]

 Roger J Smith That 10 day spell in Dec 22 was very potent cold wise, suspect the last equivalent cold 10 day spell was Dec 10. Possibly 1-10 Feb 12 might have been similiar?

[Dancerwithwings]

 Roger J Smith

Thanks Roger…..The best January I’ve ever had…. combined

[WYorksWeather]

Belated congratulations to @Roger J Smith. The GFS projection you did from mid-month showed mid to high 4s, and that was where it ended up.

I'm not backing down from my view that it usually ends up milder than the GFS projections though .

[Roger J Smith]

Agreed, GFS + 0.5 is usually a good rule. 

I looked into 10-day averages for cold spells since 1979. 

Using v2.0.1.0 data I find following results: 

 

Coldest 10d intervals 1979 to 2024

Dec 17-26 2010 ____________-4.15

Jan 6-15 1982 ______________-3.95

Dec 10-19 1981 ____________-3.51 (subzero Dec 8-9 also, see continuation below)

Jan 9-18 1987 ______________-3.16 

Feb 10-19 1985 ____________-2.48

Nov 28-Dec 7 2010 ________-2.20 (-2.26 11d Nov 28-Dec 8 )

Feb 3-12 1991 _____________-2.12 (coldest portion of 29d spell, coldest non-overlap below ^)

Jan 9-18 1985 _____________ -1.98 (-2.11 Jan 7-18, 12d)

Dec 7-16 2022 _____________-1.88

Jan 1-10 2010 ______________-1.81

Feb 6-15 1986 ______________-1.76

Feb 20 - mar 1 1986 _______ -1.75

Jan 21-30 1979 _____________ -1.49 $$ (see next entry) (note also -0.4 for 7d Dec 17-23 1978 and -0.8 for 5d Nov 27-Dec 1 1978)

Dec 30 1978 - Jan 8 1979 ___ -1.37 ( 8d avg -2.5 Dec 30 to Jan 6) (two non-overlap intervals follow) $ and $$

Dec 31 1996 - Jan 9 1997 __ -0.98 * (second part of 20d cold spell)

Feb 2-11 2012 _____________ -0.98 

Jan 16-25 2013 _____________-0.82 

Dec 24 1995 - Jan 2 1996 __ -0.79 ( 7d avg -2.19 Dec 25-31)

Dec 29 2008 - Jan 7 2009 __ -0.72

Jan 24 - Feb 2 1996 _________-0.58 (coldest average but close to Jan 29-Feb 7 )

Dec 20-29 1981 ____________ -0.35 (coldest non-overlap, -0.8 9d Dec 20-28)

Feb 10-19 1979 ____________ -0.29

Jan 22-31 1992 _____________-0.23 

Dec 22-31 1992 ____________-0.22 (Dec 25 to Jan 3 1993 also -0.20)

Dec 6-15 1991 _____________ -0.20

Feb 22 - mar 3 2018 _______ -0.20

Dec 16-25 2009 ____________-0.14

Dec 26 1985 - Jan 5 1986 __+0.07

Jan 10-19 1980 ____________ +0.23

Feb 9-18 1983 _____________+0.32

Jan 11-20 1979 ____________ +0.57 ($ see above two non-overlapping intervals before, after)

Dec 23 2000 - Jan 1 2001 __+0.60 ( 6d avg -1.29 Dec 26-31)

Jan 3-12 2003 ______________+0.60

Feb 14-23 1994 ____________+0.68

Dec 30 2020-Jan 8 2021 ____+0.72

Feb 1-10 2009 ______________+0.73

Dec 21-30 1996 ____________ +0.75 (first part of cold 20d spell, no overlap w Dec 31-Jan 9 1997 above)**

Dec 29 2001 - Jan 7 2002 ___+0.87 ( 8d avg -0.08 Dec 29-Jan 5)

Nov 20-29 1993 ____________ +0.91 (equivalent to -1 or even -2 in Jan-Feb) (+1.56 Nov 24 - Dec 3 1989)

Feb 17-26 1981 _____________+0.95

mar 23 - Apr 1 2013 _______ +1.06 (considering normal values 6-7 C quite extreme)

Jan 24 - Feb 2 1991 ________ +1.08 ^ (coldest non-overlap to Feb 3-12 very cold spell)

Feb 6-15 2021 _____________ +1.09 ( 8d avg 0.01 7-14 Feb)

also close to criterion of +1.2 or lower include

(Feb 13-22 1984 +1.26) (Jan 18-27 1984 +1.32)

(Feb 20 to mar 1 2005 +1.63) (Jan 10-19 2024 +1.38)

** (96-97) various later ten-day averages are lower but overlap part of coldest portion Dec 31 to Jan 9. Jan 10 1997 was also +0.5

To give a longer context, -4.58 for 17-26 Jan 1963, -4.07 for 11-20 Feb 1929, and -3.36 for 16-25 Feb 1947; -5.87 for 5-14 Feb 1895. 

[summer blizzard]

Impressive for Dec 22 and really underlines the strength of Dec 10.

[Dancerwithwings]

 summer blizzard

Agreed…2010 was certainly and celebrated as exceptional, on par maybe with the incredible cold we had in 87… peeps soon forget how extreme them times were

[J10]

PDFs

Jan 2024 CET.xlsxJan 2023 Summary.pdfJan 2023 Summary Overall.pdf

Monthly Scores
Just the one spot on this month, noname_weather getting 4.7c spot on.
Two others 0.1c out, Dancerwithwings and Metwatch.

Seasonal Scores
Large changes in the Top 10, however Typhoon John stays on top.

Yearly Scores
Very similar to the Seasonal scores however Norrance egdes into the top 10.

 

[Roger J Smith]

EWP confirmed as 97.2 and previous scoring posts are adjusted. In annual scoring, J10 is in lead at 17.79 points, Noname_weather is second at 17.65, Don, WYorksWeather and JeffC are 3rd to 5th. All scoring can be found a few days back in the thread (posted Tuesday 30 Jan). 

Dancerwithwings (96.0) was top scorer for January, Weather26 (also 96.0, later entry) second, PIT (95.0), jonboy (99.0) and TillyS (95.0) are 3rd to 5th (jonboy 3rd lowest error but with a late penalty).