July 2021 CET & EWP forecast contests

[Scorcher]

5 hours ago, Earthshine said:

Yep I remember July 2019 being a rather pleasant month here.  August 2020 had a fantastic first half but gradually petered away in the second half.  The CET for August 2020 was 19C+ for much of the month before a dramatic cool down later dragging the CET down.

Yes I thought the first half of last August was easily the best since 2003. As you say, it's a shame about the last third of the month which was very disappointing.

[damianslaw]

Despite the high CET, it looks a notably cool end to July.. 

[damianslaw]

Despite the high CET, it looks a notably cool end to July.. 

[Greyhound81]

On 24/07/2021 at 22:00, DAVID SNOW said:

And at months end a 0.5C  downward correction.

If not, then this justifies  my not bothering with Hadley CET  anymore, their daily figures are all over the place, and have been wrong now for many months.

In fact, i don't trust their data at all!

If you don't trust the CET, then what data do you trust?  I bet you was not saying this in April and May when we had below average temperatures.

[The PIT]

Sunny Sheffield down to 18.8C -2.0C below normal. Rainfall 63mm 98.6% of the monthly average

Looking like we will end up around 18.5C  to 18.7C using the local forecast however they tend to be too low by about two degrees.

A slightly cool look to end of the month for us but nothing drastic.

[Summer Sun]

18.6c to the 28th

2.6c above the 61 to 90 average
2.0c above the 81 to 10 average

___________________________

Current high this month 18.7c on the 23rd
Current low this month 16.7c on the 1st

[damianslaw]

CET has held at the same value past 5 days, quite surprised, here we haven't had a maxima higher than the CET value past 2-3 days.. would not be surprised to see notable downward adjustments by month's end.. may not finish in the 18s..

[The PIT]

1 hour ago, damianslaw said:

CET has held at the same value past 5 days, quite surprised, here we haven't had a maxima higher than the CET value past 2-3 days.. would not be surprised to see notable downward adjustments by month's end.. may not finish in the 18s..

Not surprising we are at the end of the month so it takes much larger changes than it would say after 5 days or 15 days to make much of a difference.

[damianslaw]

1 hour ago, The PIT said:

Not surprising we are at the end of the month so it takes much larger changes than it would say after 5 days or 15 days to make much of a difference.

If it sticks at the same value next couple of days, I'll be very surprised.

[The PIT]

Sunny Sheffield down to 18.7C +1.9C above normal. Rainfall 66.6mm 104.2% of the monthly average.

[Summer Sun]

18.5c to the 29th

2.4c above the 61 to 90 average
1.8c above the 81 to 10 average

___________________________

Current high this month 18.7c on the 23rd
Current low this month 16.7c on the 1st

[Earthshine]

If we end up on 17.7°C it would be the warmest month since July 2018 (and July 2013 before that).  That would be quite the correction downward, I'd expect more in the region 17.9-18.2°C.

[Weather-history]

On 28/07/2021 at 23:25, damianslaw said:

Despite the high CET, it looks a notably cool end to July.. 

Oddly the exact opposite of last year. 

[Roger J Smith]

Now looking like EWP could exceed 90 mm, it was 77 mm by 28th and added about 5 mm on 29th, with another 10 mm appearing likely today, small top up on the 31st could end up in the 95 mm range. 

(edit) the total only increased by 5 mm which seems a bit low for the map, but from there, another 4 mm on 30th implies 86 mm, today looks to be in the 1-2 mm range. Outcome around 88 mm perhaps. 

Edited July 31, 2021 by Roger J Smith

[North-Easterly Blast]

I think that the estimated provisional Hadley CET could be a little high this month - the Net Weather CET tracker is currently on 18.19*C, and this has for many years often been slightly higher than the final confirmed Hadley CET in general.  Metcheck have their tracker figure at just under 17.6 which has over the years often been close to the final Hadley CET, sometimes a little higher, sometimes a little lower.

This July has really been a warm month overall mainly due to a heatwave from about the 16th to 23rd, away from that spell the rest of this month has otherwise felt fairly average and nothing outstanding.  It has felt very much similar to July 2019 where an otherwise average month contained a notable five day heatwave.

Edited July 30, 2021 by North-Easterly Blast

[North-Easterly Blast]

2 minutes ago, North-Easterly Blast said:

 

 

Edited July 30, 2021 by North-Easterly Blast

[DAVID SNOW]

On 28/07/2021 at 16:31, Quicksilver1989 said:

Only when monthly temperatures are above average it seems...

The CET has to be adjusted at the end of the month as at that point all of the data is collected and the adjustments make it homogenous with the rest of the 300+ year series.

Well you've got that totally wrong, i posted last month that the running CET seemed stuck for several days and was running too LOW and should have increased twice.

Obviously you'll want to have a look for yourself in the June CET thread, and get back to me.

Thanks.

[Derecho]

1 hour ago, DAVID SNOW said:

Well you've got that totally wrong, i posted last month that the running CET seemed stuck for several days and was running too LOW and should have increased twice.

Obviously you'll want to have a look for yourself in the June CET thread, and get back to me.

Thanks.

But it wasn't running too low, looking at when you posted...


and then we look at the provisional running mean vs actuals... 

 

Looks fine to me...

Edited July 30, 2021 by Quicksilver1989

[DAVID SNOW]

On 30/07/2021 at 16:31, Quicksilver1989 said:

But it wasn't running too low, looking at when you posted...


and then we look at the provisional running mean vs actuals... 

 

Looks fine to me...

Right or wrong i comment if the CET is too high OR too low, obviously not as you implied...........

Thanks.

[Methuselah]

23 minutes ago, DAVID SNOW said:

Right or wrong i comment if the CET is too high OR too low, obviously not as you implied...........

Thanks.

How do you know whether it's running high or low?

[The PIT]

Well today is going to make a dint in our average with a max preliminary max of 15.1C. Only knocking 0.2C of the average buts a lot at the end of the month.

[Timmytour]

3 hours ago, North-Easterly Blast said:

I think that the estimated provisional Hadley CET could be a little high this month - the Net Weather CET tracker is currently on 18.19*C, and this has for many years often been slightly higher than the final confirmed Hadley CET in general.  Metcheck have their tracker figure at just under 17.6 which has over the years often been close to the final Hadley CET, sometimes a little higher, sometimes a little lower.

This July has really been a warm month overall mainly due to a heatwave from about the 16th to 23rd, away from that spell the rest of this month has otherwise felt fairly average and nothing outstanding.  It has felt very much similar to July 2019 where an otherwise average month contained a notable five day heatwave.

Not sure I go along completely with your second paragraph.  I think prior to the heatwave the month was exceptionally warm when considering the cloudy weather that accompanied it for many of us.  I think this is what has given the month a lot of its impetus which the heatwave was able to build on. I've been struck with how warm the nights have been all month. 

While very nice, I'm not sure the heatwave was particularly exceptional, bar the minima.  For example it's pretty much certain that this month will end up a fair bit warmer than July 2019, but the latter delivered up a five day period of successive daily means above 20C and a maximum in excess of anything we saw this July..

I think the longest sustained run of daily mean CETs at or above 20C was between the 8th and 17th July in 1983.  followed by 9 in August 2003 and runs of 8 in the Augusts of 1947, 1995 and 1997 and the July of 1976.

It wouldn't surprise me if this July makes it into that list as well, not so much because of the heatwave but because of the relative high minima that we've seen.    

[Roger J Smith]

Most of these debates can be resolved if people would look into the phenomenon known as rounding. The running CET recently seemed stuck on 18.6 but I think it went from 18.64 to 18.56 in one day, which is basically a drop of 0.1 even though the rounded numbers stayed the same.

In any case, it is all moot (irrelevant shall we say) since the actual CET will be determined after the fact without reference to these provisionals, they could say any old thing and it would not change the outcome which as I posted earlier is probably determined from taking an average of three data points submitted a bit later in real time (and subtracting 0.2 as advertised due to a small urban heat island effect). 

It would be pointless to analyze the provisional data either in the month or afterwards, since those numbers more or less get flushed when the official numbers are posted. 

[damianslaw]

Expect another nudge down tomorrow, probably 18.3 degree and then another to finish at 18.2 degrees. Will see if there are any corrections, a common occurrence it seems. With any, a 50 50 whether we end up in the 17s or 18 and above. 

[The PIT]

Sunny Sheffield down to 18.5C +1.7C above normal. Rainfall up to 74.1mm 116.0% of the monthly average.

Looking like 18.4C will be our final figure.