April 2024 C.E.T. and EWP contests

[Addicks Fan 1981]

Mods please put the above post in the moans thread.    

[Roger J Smith]

Dire or not, April 2024 is now top of the heap for running CET (was 0.1 back of 2011 after 12 days) ... to repeat an earlier post, top 20 include these: 

YEAR ___ CET 1-13 _ CET 1-14 ___ end result

2024 ___ 11.53 ___ 11.39 ___ ___ ?? ??

1778 ___ 11.19 ___ 10.71 ___ ____ 8.2

2011 ___ 11.18 ___ 11.08 ___ ___ 11.9

2020 ___ 10.89 ___ 10.54 ___ ___ 10.5

1926 ___ 10.59 ___ 10.47 ___ ____ 9.3

1999 ___ 10.58 ___ 10.04 ___ ____ 9.5

1894 ___ 10.42 ___ 10.29 ___ ____ 9.7

1815 ___ 10.42 ____ 9.93 ___ ____ 8.1

2014 ___ 10.35 ___ 10.31 ___ ___ 10.3

1995 ___ 10.24 ___ 10.23 ___ ____ 9.1

1835 ___ 10.15 ___ 10.06 ___ ____ 8.6

1943 ___ 10.14 ___ 10.30 ___ ___ 10.5

1865 ___ 10.05 ____ 9.99 ___ ___ 10.6

1798 ____ 9.97 ___ 10.04 ___ ___ 10.3

1792 ____ 9.95 ___ 10.16 ___ ___ 10.0

1803 ____ 9.93 ___ 10.07 ___ ____ 9.1

1827 ____ 9.90 ____ 9.83 ___ ____ 8.9

(1945 ____ 9.77 ____ 9.91 ___ ___ 10.1)

(1850 ____ 9.75 ____ 9.74 ___ ____ 9.0)

(2007 ____ 9.52 ___ 9.86 ____ ___ 11.3)

Last three are not next consecutive but of interest.

You might recall that I had a table of record warm 31-day intervals when 2024 broke a few back in Feb. 

We can now add 9 to 13 April as five additional such intervals taken down by 2024 (and no doubt also ending 14 Apr)

9.7 for 10-03 to 09-04 broke 9.6 in 1957. 

9.8, 10.0, 10.2 and 10.3 broke values of 9.6, 9.5, 9.5 and 9.6 set in 2017 ending 10-13 April. Looks to be a sure bet for interval 15-03 to 14-04 to fall also. 

In other words, if calendar months ended 9 to 13 April, 2024 would be warmest on record for them. 

 

Edited April 15 by Roger J Smith

[WYorksWeather]

Latest GFS seems to bring the high a bit further east, probably increases the chance of a warmup in the second half of the coming week. Probably not to the same extent as the last few days but should prevent the CET from falling away too much. Any finish below 10C is now unlikely in my opinion.

[Roger J Smith]

I agree, 75% of GFS dramatic cool-downs after seven days either fail to materialize or come in very weak and temporary. I don't know if it's a cumulative effect of climate warming overcoming what might have been good model development in an earlier setup, or a model flaw, but either way, it is well known even in "amateur" cli-met circles (people talk about it all the time on US weather forum too). Today (yesterday's running avg 11.5) could be our peak (hope not as it's also my forecast) but I would be surprised if we got much lower than 10.3 at any point.

Later on I will dive into the archives and see what happened in the April 2011 contest. (yes there was one ... this all started around 2006). 

[Roger J Smith]

Well I promised to take a look back, and on page 185 of "spring weather" forum I found April 2011 CET contest thread, back in those days Summer Blizzard compiled lists of forecasts and had this posted on 2nd April, I have only copied those above 11.0 (and a few late forecasts by one day noted were all in a range of 9.9 to 10.7). Long-timers will know that Craig Evans was later Lettucing Gutted and was famous for predicting high numbers all the time (after a few years of less exotic punts when we started). 

About one-third of current "regulars" were active then and a few other names have changed. If you want to know what you said for April 2011, have a look at the thread, it's interesting near the end too, as people discussed a historic month that had blown away a recent high set in 2007. Using CET legacy at the time, the scoring was done from 11.8. It has since changed to 11.9 in v2.0. So another win for Craig (to go with Dec 2015 and perhaps one or two others). Craig won on first entry at the time but now would be undisputed first.

I was amused to find that I had the same forecast in 2011 as I did this year, I hope it does as well but as you see one enthusiast went as high as 12.9 in 2011 (and finished about 8th using CET legacy). 

11.0C: Tony H

11.1C: Don

11.2C: Glacier Point

11.5C: Roger J Smith

11.6C: Atlantic Flamethrower

12.0C: Craig Evans

12.9C: Backtrack

---------

I don't think anyone was complaining about April 2011, it was quite a dry and presumably sunny month and had pleasant warm spells all along its path. Near the discussion thread in the menu I noted a long-range forecast for summer 2011 that advertised a scorcher like 1976. Well ... the best weather of 2011 was probably in April and late Sep into early Oct. 

Not sure if Atlantic Flamethrower is still active on Net-weather, but software would change username I think (and display it in Apr 2011 post), and the post is still under that name. Glacier Point is still active, I believe, in model discussion threads. I will check that point about changed user names, as I know at least three entrants in Apr 2011 now use different handles -- this is why I didn't post below 11.0, as I don't want to get into that domain. I'll let username-change people identify themselves, but the Craig Evans - Lettucing Gutted legacy in our contests is probably universally known (and celebrated) anyway. There were a couple of other temporary handles used too. The only reason I use my middle initial is because before I joined there was a Roger Smith (not me) who had joined up, but I don't think they stayed around very long (I joined in 2005 and NW started around 2003, the contests date back to around early 2006). 

Wow, 13 years have gone by ... and we're still at it. 

[WYorksWeather]

 Roger J Smith Three main reasons, I think. The first is the lack of appreciation of the different averaging methods. People often just look at the model climatologies, which frequently are 1991-2020 or in the case of the ECM the last 20 years, and forget to subtract a degree or more from the average for most non-summer months if you want to compare back to 1961-1990.

Secondly, it's common to use 850hPa temperatures as a proxy for the surface - when we have warmer than usual SSTs that doesn't work as well, and in particular night-time minima will hold up. 

Finally, sometimes I think people just eyeball from the chart - high to the west so it's a north-westerly, therefore temperatures will be below average.  When actually, a 2024 north-westerly is probably still going to come out close to average when you compare back to 1961-1990.

[BlueSkies_do_I_see]

I remember April 2011 well, as I had just become a father for the first time a couple of weeks earlier. It was indeed a warm, sunny and pleasant month. The cloth nappies dried well on the line! 

It must have finished very strongly judging by Roger's running CET chart above showing 11.08 avg for the first 13 days and finish of 11.9C.

Which was sunniest April on record?

I'm thinking 2007/2011/2015/2020 would feature high up in the charts..

Edited April 14 by BlueSkies_do_I_see

[Derecho]

Latest 12z control from the EC is pretty nondescript with high pressure but on the chilly side for a small number of days. More so in the east with Stonyhurst or Pershore often being the warmest site.

Makes sense given the overall pattern and the cooler air from the continent grazing the SE. However the EC12z control was on the colder side of the ensemble mean from the 24th to the 29th.

So the CET drops down to 9.9C here. Early 10s guesses are looking good at the moment.

[Summer Sun]

11.4c to the 14th

3.5c above the 61 to 90 average
3.7c above the 81 to 10 average

[The PIT]

Sunny Sheffield at 10.3C +2.7C above average. Rainfall 54.1mm 96.4% of the monthly average.

Will pass the average today but after that doesn't look like much in the way of rainfall at the moment.

 

[Metwatch]

19 hours ago, BlueSkies_do_I_see said:

Which was sunniest April on record?

I'm thinking 2007/2011/2015/2020 would feature high up in the charts..

Top 10 sunniest Aprils for the UK via Roost Weather: http://starlingsroost.ddns.net/weather/ukobs/ukgraphs.php?type=monthlyregional&field=year&param=Sunshine&region=UK&month=4&anom=

And out of interest the rankings for central and southern England area only:

 

Edited April 15 by Metwatch

[Frigid]

 Metwatch The 2020/2021 pair is such an interesting quirk with one being very mild and one very cold. Both being the sunniest April's on record with 2021 just beating it. 

[Derecho]

1 hour ago, Frigid said:

The 2020/2021 pair is such an interesting quirk with one being very mild and one very cold. Both being the sunniest April's on record with 2021 just beating it.

I think April 2021 has to be synoptically one of the most unusual months I can remember.

[BlueSkies_do_I_see]

Thanks for posting this. Quite frankly I am surprised.. 2021 was incredible! I remember 2020 clearly but not 2021. But it surpassed it somehow.

Edited April 15 by BlueSkies_do_I_see

[BlueSkies_do_I_see]

 Derecho it wouldn't take a huge twist to drop into the high 9s C then if we picked up an easterly towards the end of the month perhaps?

Glad I stuck with 9.6C. It may not be too far out 

[Derecho]

 BlueSkies_do_I_see Yup it wouldn't take much. We will probably end up with a chilly east and mild west of the UK, so where that boundary ends up will have a big bearing on the CET as Pershore and Stonyhurst are more western sites.

[Addicks Fan 1981]

 BlueSkies_do_I_see this final warming of the stratosphere seems to be doing damage.   

[damianslaw]

 Derecho It will be countered, western parts will see colder mins given shelter from north and east winds. 

 Frigid Also interesting as they came during 'lockdown' periods, 2021 from memory was when we could meet outside in the freezing air!

[Derecho]

11 hours ago, damianslaw said:

It will be countered, western parts will see colder mins given shelter from north and east winds. 

Yes chilly minima will be present in the west, though if away from the chillier easterly feed it could get quite warm during the day in these areas....

... but looking at the model output this morning it does look a bit on the chilly side widely into the later stages of the month with less of an east-west split. A CET of under 10C is possible.

Edited April 16 by Derecho

[Summer Sun]

11.2c to the 15th

3.3c above the 61 to 90 average
3.5c above the 81 to 10 average

[Daniel*]

These are quite cool my prediction we fall within 0.5C of 1991-2020 normal. I can’t see this month finishing remotely exceptional rather ordinary overall. 

Edited April 16 by Daniel*

[Metwatch]

 Daniel*

I think those who have went for a CET in the high 9s should be getting more optimistic now, though any guesses below 9.5C, 9.4C still seems unlikely.

Edited April 16 by Metwatch

[WYorksWeather]

 Derecho Key seems to be the extent to which we see a temporary warmup this weekend partially countering or halting the drop in the CET through the middle of this week. Then remaining uncertainty is for the final couple of days - we have a couple of outlier runs taking off to very warm territory, but nothing too robust.

Perhaps 9.5C to 10.5C the favoured range?

[The PIT]

Sunny Sheffield down to 10.1C +2.4C above average. Rainfall 64.3mm 114.6% of the monthly average.

[Roger J Smith]

Looks like 15 April will end a three-day run for 2024 at top of running CET (15th edged out 2011 at 11.1 C), and a seven-day run for top of running 31-day average (10.03 passed 1945 at 9.8, which tied 1803 in one dec). As both will be same (running CET) or higher (31-d) to 16th, 2024 will stop breaking these, and as you're discussing, probably won't return for any more spoils unless that warm spell at around weekend range locks in rather than yielding to cooler synoptics from north and east. 

It has been snowing lightly here today after three days of 15-17 C sunshine, so it's a volatile time of year.