April 2021 C.E.T. and EWP forecast contests

[North-Easterly Blast]

1 minute ago, North-Easterly Blast said:

Well last month was a cause of celebration in that it has given us the first significantly below average April (first sub 7*C) in 32 years.  The absence of cold Aprils in recent times is certainly a remarkable statistic when you consider that between 1990 and 2020 the April CET was never lower than 7.2.  A 32 year run without the April CET going under 7*C (or 7.2 to be precise) is unprecedented in the 360+ year long record.  The April 2021 CET was 6.43*C to be precise.  The mean minimum was also the coldest in the list since 1878, although prior to that in the CET record we cannot be certain that it was the lowest ever.  The absence of cold Aprils must be the most remarkable of most if not any month in the year in the last 30 odd years, and congratulations to favourable weather patterns setting up that we have finally cracked it.

 

[Roger J Smith]

From the table of forecasts, this is the unofficial CET rankings for April (with the usual caveat that late penalties have the effect of dropping scores by about one or two ranks per day late) ... subject to verification by J10 in later scoring results ... EWP forecasts are shown and the number in brackets is order of entry into the contest. 

This is the third time (according to my checking back) that all forecasts were above the outcome. The other times were March 2013 and August 2014. A report on that can be found earlier in the thread.

 

 

Rank __ CET _ (EWP) _  Forecaster 

_ 01 ___ 6.8 __ 75.0 __ Godber.1 ( 46 ) ______________

_ 02 ___ 6.8 __ 90.0 __ daniel* ( 56, 29.5 ) ___________

_ 03 ___ 6.9 __ 48.2 __ Roger J Smith ( 27 ) __________

_ 04 ___ 7.0 __ 68.0 __ Walsall Wood Snow ( 44 ) ____

_ 05 ___ 7.1 __ 36.1 __ Polar Gael ( 11 ) ______________

_ 06*___7.2 __ ------ __ Kentish Man ( L1-3 ) __________

_ 07 ___ 7.3 __ ------ __ Quicksilver1989 ( 55 ) ________

_ 08 ___ 7.5 __ 55.0 __ syed2878 ( 20 ) _______________

_ 09 ___ 7.7 __ 77.0 __ Timmytour ( 8 ) ______________

_ 10 ___ 7.8 __ 65.0 __ Frigid ( 3 ) ____________________

_ 11 ___ 7.8 __ 77.0 __ Summer18 ( 14, 9.5 ) _________

_ 12 ___ 7.8 __ ------ __ Summer Sun ( 22 ) ____________

_ 13 ___ 7.8 __ 51.0 __ Reef ( 38 ) _____________________

_ 14 ___ 7.8 __ 85.0 __ davehsug ( 51 ) ________________

_ 15 ___ 7.9 __122.6__ Kirkcaldy Weather ( 17 ) _______

_ 16 ___ 7.9 __ 59.0 __ jonboy ( 25 ) ___________________

_ 17 ___ 7.9 __ 64.5 __ Midlands Ice Age ( 33 ) ________

_ 18 ___ 7.9 __ 70.0 __ Relativistic ( 39 ) _______________

_ 19 ___ 7.9 __ 55.0 __ Mulzy ( 45 ) ____________________

_ 20 ___ 7.9 __ ------ __ Duncan McAlister ( 58 ) ________

* counts as 8th for setting best combined ranks, 7th and 8th CET move up one for that.

______________________________________________________________

best combined is a tie, Polar Gael is 5th CET and 1st EWP (6 ranking points) and Roger J Smith is 3rd in both (also 6 ranking points).

third in this category is syed2878 who is 7th CET (under the modified rules for best combined) and 9th EWP (16 ranking points).

fourth is Reef who is 13th CET and 5th EWP (ahead of late penalty BFTP) (18 ranking points).

 

 

 

 

[Timmytour]

25 minutes ago, North-Easterly Blast said:

Well last month was a cause of celebration in that it has given us the first significantly below average April (first sub 7*C) in 32 years.  The absence of cold Aprils in recent times is certainly a remarkable statistic when you consider that between 1990 and 2020 the April CET was never lower than 7.2.  A 32 year run without the April CET going under 7*C (or 7.2 to be precise) is unprecedented in the 360+ year long record.  The April 2021 CET was 6.43*C to be precise.  The mean minimum was also the coldest in the list since 1878, although prior to that in the CET record we cannot be certain that it was the lowest ever.  The absence of cold Aprils must be the most remarkable of most if not any month in the year in the last 30 odd years, and congratulations that we have finally cracked it.

I'm definitely going for a CET of 5.9C  for December this year.....

[Timmytour]

Coldest four month start to a year for 8 years and 8th coldest start to a year since 1990.

The last time there were two successive starts that were colder was in 1986 and 1987, so next year could bring an end to a 35 year run. Remarkable when you consider that in the 10 years between and including 1978 and 1987, only 1981 and 1982 were warmer!

[LetItSnow!]

11 minutes ago, Timmytour said:

Coldest four month start to a year for 8 years and 8th coldest start to a year since 1990.

The last time there were two successive starts that were colder was in 1986 and 1987, so next year could bring an end to a 35 year run. Remarkable when you consider that in the 10 years between and including 1978 and 1987, only 1981 and 1982 were warmer!

Of course I could be proved miserably wrong but I’m feeling like this could be a sub-10degC year. Models showing a generally very cool/cold first half to May as well... Nice to see, but too early to tell. Here’s hope!

[Frigid]

I genuinely was surprised to see the CET come up as 6.4C, also the minimum CET being the coldest on record beating 1917 was very impressive indeed. Shows how cold it's been this April, akin to a typical winter month.

May looks to start cold as well, could we get our first sub 10c CET for May since '96??

[Timmytour]

April 2021 is the first month since March 2013 to register in the coldest 10% of mean CET's for the month

Along with December 2010 it is only the third such month this century to register in its coldest 10%

 

[damianslaw]

31 minutes ago, Timmytour said:

April 2021 is the first month since March 2013 to register in the coldest 10% of mean CET's for the month

Along with December 2010 it is only the third such month this century to register in its coldest 10%

 

Yes quite an exception of a month, not in the same league as Dec 2010 or March 2013, but notable all the same, depth of cold at night I would say more akin to the anomalies of those two very exceptional months. In an age when it is usually warm records we talk about, it makes a refreshing change.

May looks like starting on a notably cold note as well.

[Timmytour]

51 minutes ago, LetItSnow! said:

Of course I could be proved miserably wrong but I’m feeling like this could be a sub-10degC year. Models showing a generally very cool/cold first half to May as well... Nice to see, but too early to tell. Here’s hope!

 

39 minutes ago, Frigid said:

I genuinely was surprised to see the CET come up as 6.4C, also the minimum CET being the coldest on record beating 1917 was very impressive indeed. Shows how cold it's been this April, akin to a typical winter month.

May looks to start cold as well, could we get our first sub 10c CET for May since '96??

You guys are showing a distinct lack of ambition.

In the Annual CET thread I've been wondering if we could get below 9C this year  :)

[reef]

A remarkable month. For here it was actually the coldest on record, beating 1986 by 0.1C with a mean of 5.7C. I can only speculate but I imagine its probably the coldest here since 1917.

[The PIT]

Clocked in at 6.5C -2.3C below average. 7th coldest on record the coldest night time on record for us. 12 air frosts.

Rainfall 6.1mm 10.9% of the monthly average. 2nd driest on record. 8 days of measurable rain 4 days with tray.

[Frigid]

27 minutes ago, Timmytour said:

 

You guys are showing a distinct lack of ambition.

In the Annual CET thread I've been wondering if we could get below 9C this year  

Haha that would be noteworthy after such a warm year we had previous. Not often we get sub 9 Annual CETs. Something to watch over the next few months

[Optimus Prime]

1 hour ago, damianslaw said:

Yes quite an exception of a month, not in the same league as Dec 2010 or March 2013, but notable all the same, depth of cold at night I would say more akin to the anomalies of those two very exceptional months. In an age when it is usually warm records we talk about, it makes a refreshing change.

May looks like starting on a notably cold note as well.

Technically, with the mean minimum being by a decent stretch, the coldest on record, it's comparable to all of the other years that hold the top spot (1963, 1895, 1986, 2010 etc...)

Should be mentioned that the mean maxima is bang on the average for the 61-90 ref period, but considerably below the most recent 30 year comparison.

 

[Frigid]

Just noticed the coldest min CET (1.0c, 2021) and warmest min CET for April (6.5c, 2011) are 10 years apart. An interesting statistic if you ask me. 

[North-Easterly Blast]

2 hours ago, Timmytour said:

 

You guys are showing a distinct lack of ambition.

In the Annual CET thread I've been wondering if we could get below 9C this year  

Getting an annual CET below 9*C this year would be highly unlikely in my opinion, as even at this stage it would most likely require a second half like 1993 or a repeat of Dec 2010 at the end of the year.

[North-Easterly Blast]

2 hours ago, Frigid said:

I genuinely was surprised to see the CET come up as 6.4C, also the minimum CET being the coldest on record beating 1917 was very impressive indeed. Shows how cold it's been this April, akin to a typical winter month.

May looks to start cold as well, could we get our first sub 10c CET for May since '96??

Yes it is very true that although we did have some relatively cool Mays in 2010, 2013 and 2015, there has not been a really cool May since 1996.  May 1996 was certainly notably cold, and up there in the rankings with the likes of March 2013, but the lowest May CET since then was 10.4*C in 2013.  

[Man With Beard]

4 hours ago, Roger J Smith said:

From the table of forecasts, this is the unofficial CET rankings for April (with the usual caveat that late penalties have the effect of dropping scores by about one or two ranks per day late) ... subject to verification by J10 in later scoring results ... EWP forecasts are shown and the number in brackets is order of entry into the contest. 

This is the third time (according to my checking back) that all forecasts were above the outcome. The other times were March 2013 and August 2014. A report on that can be found earlier in the thread.

 

 

Rank __ CET _ (EWP) _  Forecaster 

_ 01 ___ 6.8 __ 75.0 __ Godber.1 ( 46 ) ______________

_ 02 ___ 6.8 __ 90.0 __ daniel* ( 56, 29.5 ) ___________

_ 03 ___ 6.9 __ 48.2 __ Roger J Smith ( 27 ) __________

_ 04 ___ 7.0 __ 68.0 __ Walsall Wood Snow ( 44 ) ____

_ 05 ___ 7.1 __ 36.1 __ Polar Gael ( 11 ) ______________

_ 06*___7.2 __ ------ __ Kentish Man ( L1-3 ) __________

_ 07 ___ 7.3 __ ------ __ Quicksilver1989 ( 55 ) ________

_ 08 ___ 7.5 __ 55.0 __ syed2878 ( 20 ) _______________

_ 09 ___ 7.7 __ 77.0 __ Timmytour ( 8 ) ______________

_ 10 ___ 7.8 __ 65.0 __ Frigid ( 3 ) ____________________

_ 11 ___ 7.8 __ 77.0 __ Summer18 ( 14, 9.5 ) _________

_ 12 ___ 7.8 __ ------ __ Summer Sun ( 22 ) ____________

_ 13 ___ 7.8 __ 51.0 __ Reef ( 38 ) _____________________

_ 14 ___ 7.8 __ 85.0 __ davehsug ( 51 ) ________________

_ 15 ___ 7.9 __122.6__ Kirkcaldy Weather ( 17 ) _______

_ 16 ___ 7.9 __ 59.0 __ jonboy ( 25 ) ___________________

_ 17 ___ 7.9 __ 64.5 __ Midlands Ice Age ( 33 ) ________

_ 18 ___ 7.9 __ 70.0 __ Relativistic ( 39 ) _______________

_ 19 ___ 7.9 __ 55.0 __ Mulzy ( 45 ) ____________________

_ 20 ___ 7.9 __ ------ __ Duncan McAlister ( 58 ) ________

* counts as 8th for setting best combined ranks, 7th and 8th CET move up one for that.

______________________________________________________________

best combined is a tie, Polar Gael is 5th CET and 1st EWP (6 ranking points) and Roger J Smith is 3rd in both (also 6 ranking points).

third in this category is syed2878 who is 7th CET (under the modified rules for best combined) and 9th EWP (16 ranking points).

fourth is Reef who is 13th CET and 5th EWP (ahead of late penalty BFTP) (18 ranking points).

 

 

 

 

Great punt Roger! One of those months where you can make a big leap in the CET race if you get it right, as the pack's average error skyrockets!

[damianslaw]

Any stats for Scotland mean value for April, expect it to be very low indeed in the 5s.. 

[Weather-history]

43 minutes ago, damianslaw said:

Any stats for Scotland mean value for April, expect it to be very low indeed in the 5s.. 

It was 4.6C

1917, it was 3.1C

[Don]

7 hours ago, Weather-history said:

6.4C it is

https://www.metoffice.gov.uk/hadobs/hadcet/cetml1659on.dat

Yay, coldest April since 1986!  Always good to get a colder month these days!

[damianslaw]

5 hours ago, Weather-history said:

It was 4.6C

1917, it was 3.1C

Thanks much colder than many a winter month in England over last 20 years.

[Greyhound81]

What things are taken into consideration when the CET is adjusted downwards a the end of every month?  I read somewhere else that a 0.2 adjustment is made becuase of UHI.

[Roger J Smith]

I don't think there's much involved, they give us provisionals from stations that are easy to monitor then the final values from records being kept at three locations that maybe aren't that easy to access during the month. We find that these stations tend to run colder, especially in months with a lot of clear nights. As to the 0.2 correction, that is likely made at source to those three stations, I don't think any of the provisional values we see have been adjusted by that amount. The EWP is tracked similarly and then when they have time to go over the monthly totals they adjust the tracker value to something more permanent and that is subject to review for several months before the values finally settle about 4-5 months after each month ends (sometimes they change by up to 1 mm from one report to another, sometimes not). 

[Weather-history]

23 hours ago, Roger J Smith said:

Yes was that 1806? Just going by memory because I had a bit of a similar post back in the middle of the month. Only two of the driest Aprils were much under 40 mm, one around 20 and one around 30. And of course 2007 and 2011 are in the list of dry Aprils, many of the others IIRC were average in CET for their time and would seem a bit cool nowadays (around 8-8.5 seemed to be popular). 

In the driest rankings, I think you have go down to 1771 before you find an April with a colder CET (5.5C) and that is 42nd in the rankings will be 43 when April 2021 rainfall figure has been released. 

[Roger J Smith]

The EWP tracker reached 14 mm for April, but the final value set on the 5th could be a bit lower or higher. 14.0 mm would be 10th driest as would anything else down to about 12 mm. 

Noticed that the final CET numbers excluded one or two days that had barely broken 10 C in the preliminary figures, so now the max for the month is only 9.6 deg C and the only seven Aprils (since 1772) to have a lower maximum daily mean CET are these:

1809 (8.7), 1812 (8.8), 1989 (9.0), 1986 (9.1), 1782 (9.2), 1799 (9.3), 1879 (9.5), 

also sub-10 or 10.0: (1925 & 1941 9.6, 1973 9.7, 1860 9.9 1877 10.0). 

Even some very cold Aprils like 1837 and 1917 managed to break 10 C at least once.