Roger J Smith

I mentioned back in the thread an error in CET data base where max was lower than min for 23 Dec 1884. This was resolved in v2.0.1.0, I just noticed it today and also found a new product on site explaining a few things about that and other issues. Look for the "release notes" link on the CET home page. Apparently at one location (Ross-on-Wye) used in original research on CET years ago, a notation of +5.1 was read as -15.1, no doubt handwriting issue in old tables consulted back when CET was first developed (as the old notes were likely in F deg, I don't know what looked like what, it would be about 5 F looking like 41 F). This error persisted all through the years, I brought it to their attention along with the EWP truncation errors already discussed and resolved earlier. The reason I noticed it was that in my excel file, I was studying daily ranges and ran a program to find the largest and smallest ones. To my surprise 23 Dec 1884 was a negative range (max lower than min). I knew that had to be wrong. So the reason was discovered and now we have corrected data for 23 Dec 1884 (max of -2.4 was adjusted to 4.6). They mention in the release notes making a few other small adjustments but except for those, about 99.9% of v2.0.1.0 daily data continue on from v2.0 data.

Not very late, in fact I was posting as you were, so I will call it last of non-late entries. Table adjusted. Late period starts now ... tick tock

Table of entries for December 2023 CET _ EWP __ FORECASTER (Order of entry) ____________ CET _ EWP _ FORECASTER (Order of entry) _________ 7.0 __ --- --- __ Typhoon John ( 11 ) ______________________ 4.8 _ 103.6 __ 1991-2020 average ___________________ 6.3 _ 108.0 __ davehsug ( 41 ) ___________________________ 4.8 __ 56.0 __ summer shower ( 28 ) _________________ 6.0 _ 136.0 __ virtualsphere ( 6 ) ________________________ 4.8 _ --- --- __ Mark Bayley ( 45 ) _______________________ 6.0 __ 50.0 __ syed2878 ( 16 ) ___________________________ 4.7 _ 115.0 __ WYorksWeather ( 33 ) __________________ 6.0 __ --- --- __ Froze were the Days ( 38 ) _______________ 5.9 __ --- --- __ Summer Sun ( 37 ) ________________________4.5 __ 97.4 __ 1981-2010 average ____________________ 5.8 __ 80.0 __ The PIT ( 18 ) ______________________________ 4.5 __ 60.0 __ Leo97t ( 26 ) ___________________________ 5.8 __ 87.0 __ Reef ( 32 ) _________________________________ 4.4 __ 85.0 __ Weather26 ( 2 ) ________________________ 5.7 _ 112.0 __ I remember Atlantic252 ( 27 ) ____________ 4.4 __ 77.0 __ Somerset girl ( 49 ) ____________________ 5.6 __ 74.0 __ summer blizzard ( 20 ) ____________________ 4.3 __ 99.0 __ Wold Topper ( 57 ) ____________________ 5.6 _ 129.0 __ noname_weather ( 39 ) ___________________ 4.2 __ 80.0 __ John88b ( 8 ) ___________________________ 5.5 _ 118.0 __ chilly milly ( 13 ) ___________________________ 4.2 __ 72.0 __ gazse9 ( 9 ) _____________________________ 5.4 _ 130.0 __ Don ( 34 ) _________________________________ 4.2 __ 88.0 __ summer18 ( 17 ) ________________________ 5.4 _ 120.0 __ J 10 ( 53 ) __________________________________ 4.2 __ 90.0 __ Mulzy ( 46 ) _____________________________ 5.3 _ 119.0 __ feb1991blizzard ( 30 ) _____________________4.1 __ 89.1 __ average of all data (CET 1659-2022, EWP 1766-2022) 5.3 _ 121.5 __ snowray ( 40 ) _____________________________4.1 __ 81.0 __ Alexis J9 ( 4 ) _____________________________ 5.3 _ 110.0 __ seaside60 ( L1-2 ) _________________________ 5.2 _ 135.0 __ Frigid ( 35 ) ________________________________ 4.1 __ 95.0 __ Metwatch ( 44 ) __________________________ 5.2 _ 110.0 __ Addicks Fan 1981 ( 48 ) ___________________ 4.0 _ 100.0 __ DR(S)NO ( 29 ) ____________________________ 5.2 _ 114.0 __ February1978 ( 55 ) _______________________ 4.0 __ --- --- __ damianslaw ( 43 ) _________________________ 5.1 __ 96.0 __ moorlander ( 7 ) ___________________________ 3.9 __ 51.0 __ shillitocettwo ( 22 ) ________________________ 5.1 __ 63.0 __ SteveB ( 10 ) _______________________________ 3.9 __ 75.0 __ daniel* ( 56 ) ______________________________ 5.1 __ 98.0 __ rwtwm ( 36 ) _______________________________ 3.8 __ 75.0 __ stewfox ( 12 ) _____________________________ 5.1 __ 67.0 __Mr Maunder ( 42 ) __________________________3.8 _ 105.0 __ Midlands Ice Age ( 50 ) ___________________ 5.0 __ 83.0 __ Bobd29 ( 3 ) ________________________________3.7 __ 81.0 __ Emmett Garland ( 31 ) ____________________ 5.0 __ 80.0 __ Earthshine ( 14 ) ____________________________3.6 __ 21.0 __ Neil N ( 21 ) ______________________________ ____ __ ____ __ ____ ____ ____ ________________________________3.6 __ 72.0 __ Weather Observer ( 51 ) __________________ ____ __ ____ __ ____ ____ ____ ________________________________3.3 __ --- --- __ Kentish Man ( 54 ) __________________ 4.9 _ 106.3 __ 1993-2022 average _________________________ 3.2 __ 71.0 __ jonboy ( 24 ) ______________________________ _____________________________________________________________3.1 _ 124.0 __ godber 1 ( 52 ) ___________________________ 4.9 __ 88.0 __ methuselah ( 5 ) _____________________________3.0 _ 110.0 __ Jeff C ( 1 ) _________________________________ 4.9 __ 59.0 __ dancerwithwings ( 19 ) ______________________ 2.9 __ 64.7 __ Roger J Smith ( 23 ) _______________________ ____ ____ __ __ __ ___ ___ ___ ___ ___ __________________________2.8 __ 64.0 __ Stationary Front ( 25 ) ____________________ ____ ____ __ __ __ ___ ___ ___ ___ ___ __________________________2.8 __104.0 __ Let It Snow! ( L1-1 ) ______________________ 4.8 __ 88.0 __ Consensus __________________________________ 2.4 _ 124.0 __ prolongedSnowLover ( 47 ) ______________ _____________________________________________________________2.0 __ 96.5 __ Polar Gael ( 15 ) __________________________ 57 on-time entries, and two 1d late so far, 59 total ... median (consensus) 4.8 C ---------- ========================== EWP forecasts in order 136_virt .. 135_Frig .. 130_Don .. 129_non .. 124_pSL, godb .. 121.5_snow .. 120_ J10 .. 119_feb91 .. 118_cm .. 115_WYorks .. 114_Feb78 .. 112_IRem .. 110_ Jeff, Add,sea^ .. 108_ dave .. 106.3 _93-22 .. 105_mia .. 104_LIS^ ..103.6 _91-20 .. 100_DR(S) .. 99_WT .. 98_rwtwm .. 97.4 _81-10 .. 96.5_PG .. 96_moor .. 95_Met .. 90_Mul .. 89.1 _all ...88_meth, sum18 .. 88.0_con .. 87_Reef .. 85_wx26 .. 83 _bobd .. 81_Al J9, EG .. 80_john, earth, PIT .. 77_sg .. 75_stew, dan .. 74_sb ... 72_gaz, WxOb .. 71_jon .. 67_MrM .. 64.7 _RJS .. 64_SF .. 63 _Ste .. 60_leo .. 59_dww .. 56_sumsh .. 51_shil .. 50_syed .. 21_NN _________ 51 on-time entries, and two late (^) 1d, 53 total ... median (consensus) 88.0 mm. ============================ << LATER ENTRIES will be added to end of Sunday, 3 Dec >>>

The twelve coldest CET daily minima ... all but four are daily records (27 Nov 1904, 17 Nov 1930, 25 Nov 1952 are all second coldest values for date and 27 Nov 1915 is third coldest) ... can we join this exclusive club tonight? 1. __ -7.8 __ 24 Nov 1904 2. __ -7.0 __ 28 Nov 2010 3. __ -6.8 __ 23 Nov 1983 t4. __ -6.3 __ 27 Nov 1923 t4. __ -6.3 __ 29 Nov 2010 t6. __ -6.1 __ 17 Nov 1901 t6. __ -6.1 __ 27 Nov 1904 8. __ -5.9 __ 25 Nov 1923 t9. _ -5.8 ___ 16 Nov 1901 t9. _ -5.8 ___ 17 Nov 1930 t9. _ -5.8 ___ 27 Nov 1915 (CET legacy _ -5.8 _ 30 Nov 1919 was revised to -5.5 in v2.0) 12. __-5.7 ___25 Nov 1952 (note 23 Nov 1858 before daily minima records begin was very likely in this range as daily mean was -3.9 C).

The twelve coldest CET daily minima for Nov ... all but four are daily records (27 Nov 1904, 17 Nov 1930, 25 Nov 1952 are all second coldest values for date and 27 Nov 1915 is third coldest) ... can we join this exclusive club tonight? 1. __ -7.8 __ 24 Nov 1904 2. __ -7.0 __ 28 Nov 2010 3. __ -6.8 __ 23 Nov 1983 t4. __ -6.3 __ 27 Nov 1923 t4. __ -6.3 __ 29 Nov 2010 t6. __ -6.1 __ 17 Nov 1901 t6. __ -6.1 __ 27 Nov 1904 8. __ -5.9 __ 25 Nov 1923 t9. _ -5.8 ___ 16 Nov 1901 t9. _ -5.8 ___ 17 Nov 1930 t9. _ -5.8 ___ 27 Nov 1915 (CET legacy _ -5.8 _ 30 Nov 1919 was revised to -5.5 in v2.0) 12. __-5.7 ___25 Nov 1952 (note 23 Nov 1858 before daily minima records begin was very likely in this range as daily mean was -3.9 C).

Yesterday's report was 4.4 C and I thought I had seen different values (one colder) for previous two days than I see there today, either I got them wrong or they have been adjusted. This is why we only dropped to 7.9 C. I would guess closer to 7.5 now for outcome.

I can't say with any assurance that the CET records 1659 to 1771 are accurate or as accurate as later, but they do see to correspond to any other evidence available. There's martin Rowley's research into weather related historical evidence that he ties to CET values, and it all appears to fit reasonably well. You can see all that on his site, Premium Weather, just google UK weather 1700-1749 (as one example, he has it organized by half centuries) and it will be the first return on your search. And he has historical stuff going back into the period before 1,000 AD. It gets very anecdotal but at least we know which years were hot and which were cold, and to some extent wet and dry also. I would rate the CET as "moderately reliable" before 1720 and probably almost as reliable as after 1772 between 1721 and 1771, but as you say, we don't really know for sure and can never know, it's all we will have as a rough guide unless we get people returning from the grave and even they would not have the benefit of knowing our modern methods of measurement necessarily.

Today's CET report of 8.0 appears to be 7.95 rounded up so it could take a large drop on today's expected 2-3 C, 7.7 is possible on next report, if not 7.8. Best guess for result is 7.3 or 7.4. ... EWP added a few yesterday, not sure if all the reported values on 24h chart will apply, if so, about 4-5, but possibly a bit less if reporting periods don't overlap. Then not expected to add anything significant next 54h.

The big blizzard in Russia looks like a scene from the 1940s. Isn't this exactly why the Nazis failed to over-run the Soviet capital in Nov-Dec 1941? They got stopped by winter not Stalin, who used the delay to get his forces properly armed. CET values for winter 1941-42 are 5.6, 0.9 and 0.2. It was in fact very mild in Britain in mid-Dec 1941, and only began to turn very cold after Christmas. For predictions I will go with 2.9 C and 64.7 mm cold to dig in and resist a lot but not all of Atlantic's pushback. Winter storms could be epic around 26 to 28 Dec

I like the visuals but your data base only overlaps the daily data era 1772 to present, you could perhaps get the earlier monthly data for 1659 to 1771 to extend it back. If the graph above in quoted post were extended back you would see another peak around 1710-1739 and a cold interval centered on 1671-1700. I have all the graphs available too, on my excel file of CET data, so I could post them in future discussions. December got relatively quite cold in an interval from about 1841 to 1890 and was often coldest month of winters; that tendency actually appeared to shift even earlier with Nov taking a colder turn around decades 1901-1930. Then it was February often coldest in the period 1941-70. Recently it has been a case of which winter month sucked least, and the jury is still out on that one. It's strange that no Dec between 1677 and 1787, or 1797 to 1873, or (less strange) 1891 to 1980, was as cold as either 1981 or 2010. Those were intervals of 111, 87 and 90 Decembers that avoided going sub 0.2 C. This will be the 13th try since 2010 so you wonder how long this streak will be. Last Dec at 3.4 was coldest since 2010 so the comparable Dec futility benchmarks are: Longest previous streak all at or above 3.0 __ 16 1900-1915 (1906 was 3.0) longest all above 3.0 is 13, 1982 to 1994, 3.4 in 1992 coldest tied by 1997 to 2009, 3.1 in 2009 coldest; followed by 12, 1938 to 1949, 3.1 in 1946 coldest Longest previous streak all at or above 2.0 __ 31 _ 1684 to 1714 _ coldest 2.5 several Dec 22 _ 1743 to 1764 _ coldest 2.5 1759 23 _ 1893 to 1915 _ coldest 2.2 1899 28 _ 1982 to 2009 _ coldest 2.1 1995

EWP around 118-120 mm, the current weak outcome for the Wed-Thursday southern low implies only about five more mm to come; earlier runs were showing heavier precip and outcomes of 140-150 but now we're looking at closer to 123-125. Could change again, I suppose. CET has fallen sharply due to two days at 1.8, 1.9 means. Today appears closer to 4 C, Tuesday about same, Wed and Thurs back down to around 2 C? Those forecast values would give an outcome of 7.4 C.

So it could be a bit unclear what I was saying about intervals, the value for 24 Nov (Friday) in that case would be based on max: 0900 Friday 24 to 0900 Sat 25 min: 2100h Thurs 23 to 2100h Fri 24 and possibly even earlier for min, like 1800h 23rd to 1800h 24th ... you can see this is going to adjust more minima up, than it would adjust maxima down, compared to calendar day reporting. In a continuous warming situation over two days, you could even get a "day" with both max and min actually recorded on different days, min from previous day and max from next day. This hypothetical situation with just every three hours to simplify it, shows how that would happen: 2100h Jan 7, 19 BC ____ -20 C 2400h Jan 7, 19 BC ____ -15 C 0300h Jan 8, 19 BC ____ -10 C 0600h Jan 8, 19 BC _____ -7 C 0900h Jan 8, 19 BC _____ -4 C 1200h Jan 8, 19 BC _____ -2 C 1500h Jan 8, 19 BC _____ -1 C 1800h Jan 8, 19 BC _____ 0 C 2100h Jan 8, 19 BC _____ 1 C 2400h Jan 8, 19 BC _____ 1 C 0300h Jan 9, 19 BC _____ 2 C 0600h Jan 9, 19 BC _____ 4 C 0900h Jan 9, 19 BC _____ 7 C Reported max 7 C and min -20 C, calendar day would be 1 C and -15 C, ending 0900 for both would be 7 C and -4 C. Reported means would be -6.5, -7.0 and +1.5, so it makes a difference.

I think that is correct for reported max, min is an earlier 24h interval like 9 pm to 9 pm. So as you say, next six reports (incl today's values reported tomorrow) will be full-on cold. Unless there are odd trends, most days will reflect usual morning low and afternoon max in those reporting periods, but it won't catch a midnight low if it ends at 9 pm and it could catch a low evening value from a previous day. It is rare for max to occur overnight or into first part of next morning so that sort of data contamination would be rare. I don't know what protocols were in place for CET max and min periods before recent years. As with the choice of 1961-1990 for normals, it is quirky UK practice not followed in various other countries, can't say for all but I know for a fact US, Canada and Ireland use calendar day for reporting first order climate stats and have done so for a long time but back in the distant past they produced data from different time protocols similar to these UK protocols, and it meant that on occasion, a cold midnight low was not in data and there were never as many compensating errors in maxima, so data sets were adjusted and this caused a bit of a ruckus over "data manipulation" as it appeared to skeptics that the intent was to make the past look colder. I waded into that and said, look I am not a mainline AGW person myself but I know this is legit because you can see the data were not to modern standards, you get consecutive days with temperature gaps between ranges and that is not possible when your max and min are calendar day. (day 1 min and day 2 max will be same when a strong cold front moves in overnight).

Going back in CET records, these are the coldest consecutive judged by the value they both fell below (their average in brackets): Cold consecutive Dec _______________ notable cold average of two but not qualifying in first list 2009-10 __ 3.1 -0.7 __ 3.1 (avg 1.2) 1995-96 __ 2.1 2.7 ___ 2.7 (avg 2.4) __ 1981-82 avg 2.1 (0.1 4.1) 1962-63 __ 1.8 2.6 ___ 2.6 (avg 2.2) 1961-62 __ 2.2 1.8 ___ 2.2 (avg 2.0) __ 1927-28 avg 2.8 (2.1 3.4) (1916-17 __ 1.9 2.3 ___2.3 (avg 2.1)) __ 1889-90 avg 1.3 (3.3 -0.8) 1878-79 ___-0.3 0.7 ___0.7 (avg 0.2) __ 1886-87 avg 2.3 (1.9 2.6) (list now all significant close calls as 1878-79 is lowest for both values) (1869-70 ___ 2.8 0.6 __ 2.8 (avg 1.7)) __ 1874-75 avg 2.0 (-0.2 4.2) (1859-60 ___ 1.6 1.2 __ 1.6 (avg 1.4)) (1829-30 ___ 1.4 1.8 __ 1.8 (avg 1.6)) (1807-08 ___ 1.9 2.2 __ 2.2 (avg 2.1)) (1798-99 ___ 1.5 1.3 __ 1.5 (avg 1.4)) __ 1787-88 avg 1.8 (3.8 -0.3) __ 1783-84 avg 1.5 (2.7 0.3) before that, the lowest values 1685 to 1782 are all quite moderate: (1764-65 ___ 2.8 1.7 __ 2.8 (avg 2.3)) ___ 1727-28 avg 2.6 (3.6 1.6) and 1726-27 avg 2.7 (1.8 3.6) (1696-97) ___2.5 2.5 __ 2.5 (avg 2.5)) ___ 1715-16 avg 2.3 (1.5 3.0) earlier in the maunder min, we find lower values again (1676-77 ___ -0.5 2.0 __ 2.0 (avg 0.8)) ___ 1683-84 avg 2.3 (0.5 4.0) (1677-78) ___2.0 0.5 ___ 2.0 (avg 1.3) ____1678-79 avg 1.5 (0.5 2.5) ____ ____ ____ ____ ____ ____ ____ ____ ____ 1679-80 avg 1.8 (2.5 1.0), 1680-81 avg 2.0 (1.0 3.0) So, 2009-10 beat all but two pairs for low average CET. (1676-77 second lowest average) Since 2010 the lowest values not including 2010-2011 (-0.7 5.9) avg 2.5 are 5.7 4.9 for 2019-2020 for value exceeded (5.7), and 6.3 3.4 for 2021-22 for low two-year average of 4.9. Any value below 5.7 for 2023 will improve on both of those. ____________________________________________ Note, list is successively colder going back in records to 1878-79, with one notable case in brackets out of that sequence The list is not successively colder for average of two, in fact 2009-10 is colder for that, than all pairs since 1878-1879, edging out 1889-1890. I will post forecasts later and will then delete this post and place it in discussion portion after 2nd Dec.

EWP is currently close to 112 mm and last few runs were between 20-30 mm additional, so outcomes around 132-142. I already adjusted scoring table last night for 130 mm, any outcome in that range will produce similar results. It's quite close for positions 2 to 12 but snowray is probably safe already, only a really low outcome already passed could have threatened their lead. The exact value at end of Nov will determine rest of top ten in quite a close finish, so if you take a look, keep in mind none of the positions shown after the leader are a done deal yet. CET has as expected edged up on the last gasp of the mild regime, so the math tells us outcome is unlikely to be much lower than 7.5 C, even if the average for 24-30 Nov is 3.0 (and GFS says closer to 4.0), the outcome would be 7.4 C. For 4.0 it would be 7.6 C. It will set up a battle with 2022 for third and fourth warmest autumn (I made up a table for that early in the thread, on 6 Nov), but 2006 is safe now to hold on to first, and IIRC second (2011) required a value of 8.0 so that one could be safe also. It will end up quite close to last year's average (7.3). Actually since we're talking about it, here is the table reproduced below: Top 15 CET averages for autumn, and exact data to reveal 2023 options to tie ... Rank ____ Year _____ Avg ____ SEP _ OCT _ NOV ____ 2023 to tie _ 01 ____ 2006 _____ 12.6 ____ 16.9 _ 12.9 _ 8.0 ____ 8.7 _ 02 ____ 2011 _____ 12.4 ____ 15.1 _ 12.5 _ 9.5 ____ 8.0 _ 03 ____ 2022 _____ 12.1 ____ 14.4 _ 12.8 _ 9.2 ____ 7.3 _ 04 ____ 2014 _____ 12.0 ____ 15.1 _ 12.3 _ 8.5 ____ 6.8 _t05 ____ 1731 _____ 11.8 ____ 15.3 _ 12.3 _ 7.8 ____ 6.3 _t05 ____ 1730 _____ 11.8 ____ 15.3 _ 10.9 _ 9.2 ____ 6.3 _ 07 ____ 2021 _____ 11.7 ____ 16.0 _ 12.0 _ 7.2 ____ 6.1 _t08 ____ 1818 _____ 11.6 ____ 13.3 _ 12.0 _ 9.5 ____ 5.7 _t08 ____ 1729 _____ 11.6 ____ 16.6 _ 10.1 _ 8.1 ____ 5.7 _t10 ____ 1959 _____ 11.5 ____ 14.9 _ 12.6 _ 7.1 ____ 5.5 _t10 ____ 1949 _____ 11.5 ____ 16.3 _ 11.7 _ 6.6 ____ 5.5 _ 12 ____ 2005 _____ 11.5*____ 15.2 _ 13.0 _ 6.1 ____ 5.3 _ 13 ____ 2009 _____ 11.4 ____ 14.3 _ 11.4 _ 8.6 ____ 5.3 _t14 ____ 2001 _____ 11.4 ____ 13.4 _ 13.2 _ 7.5 ____ 5.0 _t14 ____ 1978 _____ 11.4 ____ 14.1 _ 11.7 _ 8.3 ____ 5.0 ------------------- (note: in above table, order is from metoffice table, ties are established by me if two-decimal average is a tie (or if total of three autumn months is same)). * ... even so, their calculations seem to be based on some kind of weighting, for example, 2005 works out to 11.43 in the equal weight system used in CET legacy with a two-decimal table. 2005 is actually tied with 2009 in terms of total, but as their system came to different one-decimal values, I did not show a tie for them. Notice three in a row in list 1729-31 and 2023 will repeat this feat. 2020 is listed as 30th (11.0), one of six and the last of them to appear. Interesting to see that warmest Sep and Oct are in list but warmest Nov (1994) was part of a 10.9 average and four years are listed 31st to 35th (will become 32nd to 36th after 2023 slides into top ten). 1994 is given as second last of those four so appears in 34th about to be 35th. ________________________ Also from a discussion back on page four, it was stated that to beat 2022 for annual CET, it would require Nov and Dec to total 15.0, so as we are headed for 7.5 or so, it will take a repeat of that for a very mild Dec, otherwise 2023 will be fighting it out with 2014 for second (and that would take a fairly high Dec outcome also).

EWP currently around 113 mm, GFS guidance not quite as dry as previous days, now adding 25-30 mm to total by end of Nov (for near 140 mm outcome) ... would take a real deluge in Dec near record values to get past second place for yearly rainfall now and first (after 140 verified) would require a new Dec record. Probably a top five to top ten range is more realistic. CET will likely edge up to 8.7 or even 8.8 before dropping away steadily after Friday, but I can't see it falling below 7.5; assuming 8.8 after 23 days, last seven would need to average 5.7 to drop average to 8.0, and 3.4 is needed to drop to 7.5; current GFS guidance suggests 7.8 or 7.9 is likely outcome. I won't be surprised if end of Nov disturbances intensify closer to time and bring a wintry mix of precip to central England around 28-30 Nov, so EWP could go a bit above projections, and it could edge up CET outcome if last two minima are forced up a bit.

CET would take quite a tumble near end of November if guidance is correct, likely to stay in 8s for a few more days but would be falling at a rate of about 0.3 per day towards end. Low 7 range is probably favoured at present. EWP at around 108 mm, GFS dry to end of Nov and adds only about 5 mm to it; if correct, will make for a close finish to contest as Bobd29, Summer Shower, Leo 97t and Weather Observer would all score well and current leader snowray, as well as Reef, would be adding only a little to their totals. I often post a preliminary scoring table, but it appears to be a photo finish where several of current top seven would win or finish second if they hit their forecast closest or top three scores, although Reef and JeffC are positioned too close to snowray to pass in any outcome and Summer Shower at 94.0 appears to be unable to gain on several higher forecasts now; instead of a preliminary table, I will post top scores after October and forecasts for Nov without any new scoring suggestions; the table of forecasts on page three shows 55 forecasts so scoring levels will be about 0.18 apart and at a finish of around 113 mm, only two or three low forecasts would join the higher set above 150 in being low scores, snowray probably needs to see a total closer to 130 mm to see off the challengers but without working it out in detail it looks like snowray could be safe in any event once a few additional raindrops hit the EWP gauge. Bobd29 had the only realistic chance of overtaking. (Nov 25 edit _ I have posted preliminary scoring now for 130.1 mm as we close in on an actual outcome.) (Dec 2 _ tracker ended at 127.7 for NOV, will wait for table value 5 Dec to edit again) ___________________________ Current EWP contest scores and Nov forecasts (scores now adjusted) Rank (prev) _ FORECASTER ________ n __ TOTAL PTS ___ AVG ERROR (rank)__ Nov forecast, score (rank) _01 __ 01 ___ snowray _____________12 ___ 84.56 ________ 28.42 ( 5 ) _ ( 6 ) ____157.0 ___ 5.14 (28) _02 __ 03 ___ bobd29 ______________12 ___ 79.29 ________ 27.85 ( 3 ) _ (t4) ____ 103.6 ___ 5.30 (27) _03 __ 08 ___ February1978 ________12 ___ 79.24 ________ 28.80 ( 6 ) _ (13) ___ 132.0 ___ 9.64 ( 3 ) _04 __ 02 ___ Reef _________________ 12 ___ 78.81 ________ 29.43 ( 8 ) _ ( 3 ) ____172.0 ___ 2.80 (41) _05 __ 06 ___ Leo97t _______________12 ___ 78.47 ________ 29.22 (10) _ (11) ____120.0 ___ 7.74 (14) _ (2nd ent) _06 __ 07 ___ Weather Observer ___12 ___ 78.18 ________ 29.29 (11) _ (12) ___ 121.0 ___ 8.20 (11) _07 __ 05 ___ Jeff C _________________12 ___ 77.79 ________ 29.06 ( 7 ) _ (10) ____145.0 ___ 6.66 (20) (2nd ent) _08 __ 09 ___ Summer Shower_____ 11 ___ 75.85 ________ 27.02* ( 1 )__( 1 ) ___ 94.0 ____3.46 (37) _09 __ 08 ___ virtualsphere ________ 12 ___ 75.83 ________ 28.22 ( 4 )_ ( 7 ) ____149.0 ___ 6.22 (22) _10 __ 14 ___ J 10 ___________________12 ___ 74.54 ________ 29.17 ( 9 ) _ (14)____130.0 ___10.00 ( 1 ) _11 __ 13 ___ DR(S)NO _____________ 12 ___ 71.83 ________ 31.90 (16) _ (18) ___ 117.1 ___ 7.12 (17) _12 __ 19 ___ Midlands Ice Age ____ 12 ___ 70.94 ________ 33.39 (19) _ (22) ____134.9 ___ 9.28 ( 5 ) _13 __ 11 ___ jonboy _______________12 ___ 70.35 ________ 32.82 (17) _ (17) ____162.0 ___ 4.42 (32) _14 __ 10 ___ Emmett Garland _____12 ___ 69.13 ________ 31.58 (14) _ ( 8 ) ____186.0 ___ 1.20 (49) _15 __ 16 ___prolongedSnowLover _12 ___ 69.08 ________ 29.90 (13) _ ( 9 ) ____103.0 ___ 4.92 (29) _16 __ 20 ___ seaside60 ____________12 ___ 68.50 ________ 35.10 (24) _ (30) ____ 120.0 ___ 7.24 (16) _(4th ent, 1d late) _17 __ 12 ___ Polar Gael ____________12 ___ 66.68 ________ 34.68 (22) _ (16) ____ 75.2 ___ 1.60 (47) _18 __ 18 ___ summer18 ___________ 12 ___ 66.34 ________ 31.75 (15) _ (15) ___ 101.0 ___ 4.54 (31) _19 __ 17 ___ Mulzy ________________ 12 ___ 66.43 ________ 34.67 (21) _ (20) ____ 97.0 ____ 3.72 (36) _(2nd ent) _20 __ 15 ___ Roger J Smith _________12 ___ 66.25 ________ 29.54 (12) _ ( 2 ) ____182.5 ___ 1.86 (46) _21 __ 21 ___ Stationary Front _____ 12 ___ 65.91 ________ 33.23 (18) _ (19) ____112.0 ___ 6.40 (21) _23 __ 22 ___ dancerwithwings _____12 ___ 62.94 ________ 36.90 (33) _ (28) ____ 97.0 ___ 3.82 (35) _22 __ 23 ___ Feb1991Blizzard _____ 12 ___ 61.42 ________ 35.83 (28) _ (t23) ____159.0 ___ 4.78 (30) _24 __ 24 ___ Wold Topper _________ 12 ___ 60.87 ________ 36.83 (32) _ (31) ____ 103.7 ___ 5.49 (26) _25 __ 27 ___ Mr Maunder __________12 ___ 59.42 ________ 36.82 (31) _ (32) ____111.0 ___ 6.04 (23) _26 __ 30 ___ Godber 1 _____________12 ___ 58.20 ________ 36.05 (29) _ (38) ____126.0 ___ 9.46 (4) _27 __ 32 ___ rwtwm _______________ 12 ___ 57.57 ________ 34.75 (23) _ (35) ____124.0 ___ 8.92 ( 7 ) _28 __ 26 ___ daniel* _______________ 12 ___ 56.24 ________ 42.23 (46) _ (42) ____ 80.0 ____ 2.20 (44) _29 __ 33 ___ The PIT _______________12 ___ 55.86 ________ 39.97 (44) _ (46) ____120.0 ___ 7.64 (15) _(3rd ent) _30 __ 25 ___ I Remember Atl252 ___11 ___ 55.49 ________ 39.08*(40) _ (29) ___188.0 ___ 1.00 (50) _31 __ 31 ___ summer8906 __________8 ___ 54.68 ________ 27.43*( 2 ) _ (t4) ___110.0 ___ 5.86 (24) _32 __ 36 ___ davehsug _____________12 ___ 52.81 ________ 38.67 (39) _ (43) ____124.0 ___ 7.26 (9) (2nd ent, 1d late) _33 __ 28 ___ Don __________________ 12 ___ 52.71 ________ 39.92 (43) _ (t33) ____185.0 ___ 1.46 (48) _34 __ 29 ___ Weather26 ___________ 11 ___ 52.41 ________ 37.25*(34) _ (t23) ___ 84.0 ____ 2.40 (43) _35 __ 38 ___ noname_weather_____11 ___ 50.37 ________ 36.08*(30) _(t33) ____121.0 ___ 8.10 (12) _ (2nd ent) _36 __ 34 ___ summer blizzard _____ 12 ___ 49.45 ________ 39.80 (41) _ (41) ____ 98.0 ___ 4.08 (34) (2nd ent) _37 __ 37 ___ Methuselah ___________12 ___ 48.05 ________ 40.92 (45) _ (45) ___ 107.0 ___ 5.68 (25) _38 __ 43 ___ stewfox ________________ 8 ___ 46.59 ________ 35.12*(25) _ (32) ___ 135.0 ___ 9.10 ( 6 ) _39 __ 35 ___ shillitocettwo _________12 ___ 45.10 ________ 49.32 (55) _ (51) ____ 44.0 ___ 0.00 (55) _40 __ 42 ___ Frigid _________________ 12 ___ 46.10 ________ 44.42 (50) _ (54) ____120.0 ___ 6.58 (13) _41 __ 40 ___ SteveB ________________12 ___ 44.62 ________ 44.21 (49) _ (47) ____ 98.0 ___ 4.18 (33) _42 __ 45 ___ Metwatch _____________11 ___ 44.85 ________ 42.72*(47) _(50) ____123.0 ___ 8.38 (10) _43 __ 46 ___ Moorlander ___________12 ___ 44.18 ________ 43.54 (48) _ (53) ____ 130.0 ___ 9.90 (2) _ (2nd ent) _44 __ 39 ___ Mapantz _______________ 8 ___ 42.18 ________ 35.38*(26) _ (26) ____ no fcst _45 __ 41 ___ Neil N _________________11 ___ 41.75 ________ 45.57*(52) _ (49) ___ 90.0 ___ 3.10 (39) _46 __ 44 ___ syed2878 _____________ 12 ___ 41.12 ________ 45.15 (51) _ (48) ____ 90.0 ___ 2.90 (41) (3rd ent) _47 __ 49 ___ chilly milly _____________12 ___34.34 ________ 51.94 (56) _ (56) _____ 79.0 ___ 2.00 (45) _48 __ 47 ___ DiagonalRedLine ______ 6 ___ 33.52 ________ 35.80*(27) _ (25) ____ no fcst _49 __ 53 ___ catbrainz _______________8 ___33.28 ________ 39.88*(42) _ (44) ____144.0 ___ 6.94 (18) _50 __ 48 ___ Norrance ______________ 8 ___ 32.65 ________ 37.50*(35) _ (37) ____ no fcst _51 __ 50 ___ freeze _________________ 5 ___ 31.95 ________ 33.56*(20) _ (21) ____ no fcst _52 __ 51 ___ B87 ____________________7 ___ 30.21 ________ 38.54*(38) _ (36) ____ 90.0 ___ 3.00 (40) _(2nd ent) _53 __ 52 ___ SLEETY ________________ 7 ___ 27.10 ________ 38.14*(37) _ (40) ____ no fcst _54 __ 54 ___ Earthshine ____________10 ___ 26.69 ________ 49.18*(54) _ (55) ____ 70.0 ___ 0.60 (52) _55 __ 55 ___ Cymro _________________ 4 ___ 26.11 ________ 36.88 (---) _ (---) ____ no fcst _56 __ 56 ___ sunny_vale ____________ 9 ___ 26.01 _________ 46.88 (53) _ (52) ____ 87.0 ___ 2.60 (42) _57 __ 57 ___ Kirkcaldy Weather _____ 5 ___ 19.01 ________ 37.60*(36) _ (39) ____ no fcst _58 __ 58 ___ Coventry Weather _____ 2 ____19.00 _________ 8.25 (---) _ (---) ____ no fcst _59 __ 59 ___ Blast From the Past ____ 4 ___ 18.63 _________44.13 (---) _ (---) ____ no fcst _60 __ 60 ___ Somerset Girl ___________4 ___ 17.95 _________49.03 (---) _ (---) ____ 60.0 ___ 0.20 (54) _61 __ 61 ___ Thundery Wintry Showers __ 4 ___ 17.04 ________ 32.58 (---) _ (---) ____ no fcst _62 __t66___ Alexis J 9 _______________ 2 ____16.76 _________ 8.65 (---) _ (---) _____145.0 ___ 6.76 (19) _63 __ 72 ___ mazelike ________________3 ____16.71 ________ 33.70 (---) _ (---) ____137.0 ___ 8.56 ( 8 ) __9 lev _64 __ 62 ___ Weather Enthusiast91 __2 ___ 15.86 ________ 21.25 ( ---) _ (---) ____ no fcst _67 __ 65 ___ john88b ________________ 3 ___ 11.92 ________ 31.40 ( --- ) _ (---) ___ 67.0 ___ 0.40 (53) _74 __ 77 ___ WYorksWeather _________2 ____ 7.68 ________ 63.65 (---) _ (---) ____190.0 ___ 0.80 (51) (only Nov entrants are shown after 62nd place in annual contest, table will later include all entrants for contest year) (only entrants with 5-9 entries have a ranked adjusted average error) ========================= (7.6) _(9.7) __ Consensus _____________ 12 ___ 76.40 _______ 31.58 (14.0) (17.9) __120.0 ___ 7.84 (13) (9.2) _(5.4) __ 1981-2010 average _____12 ___ 75.48 _______ 29.06 ( 7.1) _( 6.9) __100.4 ___ 4.50 (31.2) (10.7) (10.6) __1991-2020 average ____12 ___ 72.40 _______ 29.78 (12.7) _( 9.7) __106.1 ___ 5.62 (25.3) (12.1)(11.7) _ 1993-2022 average _____ 12 ___ 70.92 _______ 30.50 (13.3) _(11.1) __104.7 ___ 5.55 (25.7) ___________________________ (EWP forecasts in order) 1-2 130_J 10, Moor ... 3 132_Feb78 ... 4 126_godb ... 5 134.9_mia ... 6 135_stew ... 7-9 124_rwtwm, dave^ ... 8 (9) 137_maze ... 10 123_met ... 11-12 121_WxOb, non ... 13-16 120_Frig, leo, PIT, sea60^ ... 17 117.1_DR(S) ... 18 144_cat ... 19-20 145_Al-J9, Jeff ... 21 112_SF ... 22 149_virt ... 23 111_MrM ... 24 110_sum8906 ... 25 107_meth ... (25.3) 106.1_91-20 ... (25.7) 104.7_93-22 ... 26 103.7_WT ... 27 103.6 _bobd29 ... 28 157_snow ... 29 103_pSL ... 30 159_Feb91 .. 31 101_sum18 ... 31.2 100.4_81-10 ... 32 162_jon ... 33-34 98_Steve, sb ... 35-36 97_dww, mul ... 37 94_sumsh ... (37.1) 93.8_alldata ... 38-40 90_NN, B87, syed... 41 172_Reef ... 42 87_sv ... 43 84_wx26 ... 44 80_dan ... 45 79_cm ... 46 182.5_RJS ... 47 75.2_PG ... 48 185_Don ... 49 186_EG ... 50 188_I rem ... 51 190_WYorks ... 52 70_earth ... 53 67_john ... 54 60_sg ... 55 44_shil

On behalf of J10 and myself, welcome to another new competition year with the winter season of 2023-24 fast approaching. Thanks also to Summer Sun and the PIT who contribute daily updates most of the time. ... and of course thanks to you, the loyal contest entrants and supporters. ... There has been a temperature (CET) forecast contest running on Net-weather since winter of 2005-2006, and the scoring system devised by J10 was introduced just a few years into that period. The EWP contest is newer, and has been going for six years now and began in Dec 2017 for the 2017-18 contest year. The contests include the CET forecast and the (optional) EWP forecast, with some guidance provided in two sections below ... CET averages and extremes for December --- all CET values 1981 to 2022 are in the table --- they are in highlighted type to make them easier to find --- --- --- bold type for warmest, italic for middle and underlined for the coldest thirds of these 42 most recent years. --- --- --- due to ties for 4.8 C there are 15 in total among the middle third and 12 for the coldest, 14 for the mildest. ... all values in the CET contest have been converted to v2.0, including the averages for various intervals. 13.0 ... warmest daily mean, 19th 2015 12.9 ... 2nd warmest daily mean, 31st 2021 12.7 ... previous (to 2015) warmest daily mean, 12th 1994 9.6 ... warmest December 2015 8.1 ... second warmest December 1934 7.9 ... third warmest December 1974 7.7 ... fourth warmest December 1852 7.6 ... fifth warmest December 1733 7.5 ... sixth warmest December 1710 7.4 ... tied seventh warmest Decembers 1828, 1843 7.3 ... 1988 (tied ninth warmest with 1857, 1898) 7.2 ... tied 12th warmest 1842, 1868, 1900 __ values and ties outside modern interval no longer noted, 7.0 and 7.1 have no instances in v2.0 __ 6.8 ... 2018 6.4 ... 2006 6.3 ... 2013, 2021 6.2 ... 1985, 1994 6.1 ... 1986 5.9 ... 2011, 2016 (in CET legacy there never was a 5.9 recorded, now also with 1977 there are three) 5.7 ... 1999, 2019 5.6 ... 2002 5.4 ... 1983, 1987, 1998, 2000 5.3 ... 1993, 2004 5.1 ... 1984, 2014 5.0 ... average for 2001-22 4.9 ... average for 1971-2000, 1993-2022, also 2007, 2020 4.8 ... average for 1991-2020, also 1999 4.7 ... 1989, 2012, 2017 4.6 ... average for 1901-2000 and 2003 4.5 ... average for 1961-90, 1981-2010 ... and 1991 4.3 ... 2005 4.1 ... 1982, 1990 4.1 ... average for 1659-2022 (all 364 years, 4.10 C) 4.0 ... average for 1801-1900 3.9 ... average for 1701-1800 3.5 ... 2008 3.4 ... 1992, 2001, 2022 3.4 ... average for 1659-1700 3.1 ... 2009 2.7 ... 1996 2.1 ... 1995 0.1 ... 1981 (8th coldest December) -0.2 ... 1874 (7th coldest December) -0.3 ... 1788, 1796, 1878 (tied 4th coldest Decembers) -0.5 ... third coldest December 1676 -0.7 ... second coldest December 2010 -0.8 ... coldest December 1890 -10.8 ... lowest daily mean 25th 1796 _______________________________________________ Enter your forecast before midnight on Thursday 30 November, or with the increasing late penalties for entries 1-3 Dec. (earlier material based on CET legacy temps ...) As you might expect, the Maunder period produced cold Decembers, the mean was as low as 3.2 (1665 to 1694). It then rose as high as 4.29 by 1709-38. There was a colder period than any in the Maunder; the lowest 30-year average was 3.09 from 1783 to 1812; rounded off 1784 to 1813 was equal. The running mean climbed as high as 4.61 for 1823-52 before falling back to 3.48 for 1867-96. Decembers in the first third of the 20th century were generally a bit milder than the mid-century period, means as high as 4.73 were reached in 1893-1922 and 1907-36. The lowest since those peaks was 4.33 for 1923-52. The last time that the running mean was 4.5 was 1957 to 1986. The table above tracks the changes since then, but worth noting that the cold December of 2010 dropped the running mean from 4.84 to 4.63 but it then went back up to 4.82 for 1982 to 2011 as that period dropped the cold December of 1981 (mean 0.3). 1981-2010 was the only 30-year mean at 4.6 after 1960-89. (note, v2.0 means have dropped 0.1 to 0.2 from CET legacy values, in recent decades. Dec 2000 dropped by a larger amount due to large adjustments during a cold spell near the end of the month -- this may explain why some of the values in the table appear to be "off" slightly from what you might recall from the CET legacy numbers, for example, 2015 used to average 9.7, and 1934 used to be tied with 1974 at 8.1 ... Dec 1981 has fallen from a mean of 0.3 to 0.1 in the new set). Note: updated to v2.0.1.0. _______ _ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _ ________ Optional EWP (Precip) Contest -- details The EWP contest now enters its seventh year. It remains entirely optional, in the first six years more than two-thirds of the regular temperature forecasters entered this second contest. (there were no precip-only forecasters). This fraction has increased to about 90 per cent and scoring for combined forecasts is now regularly included. The contest asks you to predict an amount in mm (not a percentage) for this statistic. Any forecasts entered as percentages are converted using 1991-2020 averages. A tracker (on EWP website) gives approximate values one day late, then you will have to be patient as Hadley EWP post their final numbers around the 5th of each month. Then the practice is to tweak the numbers through the following several months, but we ignore those later adjustments for contest scoring (it would be a lot of work and very little would change). For December, here are the averages and extremes for your guidance. Data (from the Hadley EWP tables) go back to 1766. The last fourteen December EWP amounts appear in the table below. Both 2010 and 2012 qualified as min and max values for the period 1981-2022. ... the average of these past fourteen Decembers is 110.5 mm. It can be seen from the 30-year normals and that last figure, that a general increasing trend is underway for Dec EWP. Max 1766-2022 ____193.9 mm (1876) Max since 1981 ___ 175.2 mm (2012) ____2020 _______ 159.2 mm ____2015 _______ 145.9 mm ____2013 _______ 134.2 mm ____2019 _______ 121.4 mm ____2018 _______ 116.0 mm ____2011 _______ 113.6 mm ____2017 _______ 113.4 mm _ mean 2009-22 __ 110.5 mm ____2009 _______ 109.1 mm _ mean 1993-2022 _ 106.3 mm ____2021 _______ 105.0 mm Mean 1991-2020 __103.6 mm ____2022 _______ 102.2 mm Mean 1981-2010 __ 97.4 mm Mean 1766-2022 __ 89.1 mm (all 257 years of data) ____2014 ________ 77.3 mm ____2016 ________ 41.3 mm Min since 1981 ___34.1 mm (2010) Min 1766-2022 ____ 8.9 mm (1788) ____________________________________________________ Note, the highest 30-year mean of December EWP was 106.6 mm (1896-1925). The lowest was 67.5 for 1864-1893. Since the peak value the lowest was 84.8 mm (1925-54). It has been gradually increasing since then and is now within 0.3 mm of the earlier peak. Although Dec 2022 had a near average total, it replaced 1992 in the recent 30-year average and added 23.6 mm to that value, resulting in a slight rise. For 1994-2023 to take over the lead, the value required will be about 181 mm because 1993 was quite a wet December at 172.1 mm. Your forecast should be in mm with one decimal allowed. If you enter a percentage, that will be applied to 1991-2020 mean of 103.6 mm to derive your contest entry. Any number that appears without a % sign or mm, will be taken as that number of mm, with .0 added. It will be up to you to clarify your contest entry. Deadlines are the same as the temperature contest. EWP late penalties are 0.3 points per day (scoring runs from zero to 10.0 points each month). ______________________________________________________ Note that in both contests, there is a scoring deduction applied to forecasts of similar rank submitted later than others. We encourage you to enter each month as the contest year results depend on entering at least ten of the twelve contests. There are seasonal sub-contests which is why we start the contest year in December rather than January. Once you have missed three contests, you are no longer scored in the main CET scoring table, and while the EWP does not divide into two tables, effectively by scoring no points for three contests you are probably not going to finish among the top 20-25 total points. Good luck !!

It is difficult to visualize from recent years, but November was solo coldest month of nine (extended) winters: 1782-83 (2.3 1782), 1851-52 (3.1 1851), 1858-59 (4.3 1858), 1862-63 (3.2 1862), 1871-72 (3.4 1872), 1910-11 (3.2 1910), 1915-16 (2.8 1915), 1919-20 (3.3 1919), 1988-89 (5.0 1988), also tied coldest three winters: 1675-76 (4.5 1675 with Dec 1675) and 1923-24 (3.3 1923 with Feb 1924) and 1942-43 (4.9 1942 with Jan 1943) (so at least a share of 12 winters) ... It was also second 19 coldest times, 3 of those ties for second: second to Dec _ 1758-59 (5.7 vs 3.9), 1786-87 (3.3 vs 2.8), 1816-17 (3.9 vs 3.1), 1925-26 (3.6 vs 2.8), 1989-90 (6.0 vs 4.7), 2019-2020 (6.2 vs 5.7) second to Jan _ 1684-85 (3.0 vs 0.5), 1705-06 (3.9 vs 2.8), 1760-61 (5.7 vs 5.4), 1789-90 (4.6 vs 4.3), 1965-66 (4.5 vs 2.9), 2013-14 (6.1 vs 5.8), 2016-17 (5.5 vs 4.0) second to Feb _1750-51 (4.0 t Jan, vs 1.5), 1905-06 (4.9 t Dec, vs 3.1), 1993-94 (4.5 vs 3.2) second to mar _ 1746-47 (3.3 t Jan, vs 2.5), 1795-96 (4.5 vs 4.2), 1868-69 (4.9 vs 3.8),

EWP currently about 93 mm, GFS says 130-140 is most likely end point. Agree mid-7 outcome for CET looks plausible, will briefly rise to near 9 C over weekend and fall off in stages afterwards.

EWP is around 80 mm now and GFS only adds on about 20 more, but its cool, dry outlook would need to verify 10-15 days into the future, a big unknown that also affects CET projections. In the short term, CET could rise a bit to near 9.0 by 19th before falling away, into at least the 7s if not 6s eventually. But same doubt applies to any long-range trend, it's a wait and see on these outcomes.

Anyone going cold for Nov 2023 will be ecstatic over current GFS guidance, it drops CET steadily into 6s towards even upper 5 range. It may stay around 8 for a few days now before starting into a decline.

This is a really deep dive, but just so people know, the differential quoted for 61-90 is not done for one dec, but for two, and so you can see 0.1 changes day to day in the 61-90 end value if you're using one dec, for instance, if today was 8.64 and 61-90 average was 6.48 (not saying these are actual values) then they would say 2.2 above average even though in one dec it would be 2.1 (8.6 vs 6.5) so, since the website only shows one dec, you think the 61-90 average is 6.4 but actually it is 6.5 ... this happens on a few days and can go either way, so you can't always calculate the 61-90 average directly. I wasn't told this but figured it out back in 2022 when I was trying to figure out what was happening to the reporting when it changed on their site. At first I could see they had switched to end of June (when I was looking into it) but day to day the back-calculation to 61-90 kept changing up and down in a narrow range. So I worked out second dec and found out the cause. This end value results in chaos in spring and fall, less obvious in January and July when values are fairly flat. In spring it appears 61-90 CET is a lot higher than 81-10, at least for first half, the fact that 61-90 is about 0.5 colder than 81-10 at end starts to decrease the strange look before end (of April especially). In fall you get this large positive differential that persists to end because 61-90 is now about 0.5 lower than current averages. I can't believe they continue to use 61-90 and I wonder if 71-00 will ever get a period of usage or they would just go straight to 81-10 or 91-20? Perhaps in 2052 people will be wondering when the old 81-10 averages will get the hook. Let\s hope they can say "but it doesn't really bother us because 81-10 is 0.1 higher than 21-50" but I won't put any cash on that proposition.

Agreed but I will leave it to S Sun how he wants to organize his posts. I could work out 61-90 running averages too, and we would have a better basis for reporting. I prefer to have running averages because obviously Nov is going to be a lot higher for CET at start than finish, usually.

EWP is around 61-62 mm and GFS grid average is around 40 mm (mostly around 30 with larger amounts in west) so by 27 Nov if it verifies, around 100 mm near end of November. CET outlook is a blend of quite mild spells mid-week and near end of run, and cooler days now, and in between two mild spells. Would say mid 7 to possibly 8.0 look well positioned but a lot depends on later second mild spell not yet into reliable forecast range. FWIW maps for 27 Nov at end of run would suggest storm potential around 29 Nov.