This thread is for all comments, discussion and analysis of temperatures in the UK during October, with particular emphasis on the Central England Temperature (CET), for the simple reason that it is the longest running temperature series in the world with over 360 years of data. But you can comment on any interesting temperature statistics or data from across the UK, including your own back yard.  

September has been a close to average month.  

For those taking part in the competition all CET predictions for October should be sent directly to me via the forum private message system. Do not post them directly into the thread. 

The deadline for predictions is 2359 on Monday evening (30th). 

Now on to some data for October

Historic CET summary for October

1971-2000 10.4C (30 years)  

1981-2010 10.7C (30 years)  

1999-2018 11.2C (last 20 years)  

October last year was average with 10.6C. Prior to that we have a run of quite warm October's especially 2017 with 12.4C and 2013 and 2014 both with 12.5C. 2008 and 2012 were both cool with 9.7C. 

Here is a chart of the October CET for all years since 1961: 

Direct link to chart

Latest model output 850hPa and T2m temperatures - 29 Sep 

SHORT RANGE (2 weeks)

GEFS (06z) - Lots of scatter

https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gfs&var=2&run=06&lid=ENS&bw=

T2m temperatures look fairly average after a short cold snap initially

https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gfs&var=5&run=6&lid=ENS&bw=

GEM ENS (00z) - Similar to GFS although the ENS mean is higher. But huge scatter.

https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gem&var=2&run=0&lid=ENS&bw=

T2m's  

https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gem&var=5&run=0&lid=ENS&bw=

The 00z ECM ENS T2m temperatures for De Bilt are similar to the other models

http://cdn.knmi.nl/knmi/map/page/weer/waarschuwingen_verwachtingen/ensemble/detail/ensemble-verwachtingen-detail10.png

LONGER RANGE

Met Office contingency planners outlook  

Not yet issued

Monthly outlook at BBC website

Cool start but potentially turning milder later in the month (but this assumes that hurricane activity starts to wind down)

https://www.bbc.co.uk/weather/outlook  

ECM 

A cool start in the east and then just generally fairly average for the rest of the month

meTz20190926_0000+26400.png

meTz20190926_0000+43200.png

meTz20190926_0000+60000.png

meTz20190926_0000+76800.png

CFS

Close to or slightly above average

cfs-8-10-2019.png

JMA

Looks fairly westerly based on the 500mb height anomalies for the next 28 days

Y201909.D2512.png 

Bid is placed. I like to get in early.

Big news!

I estimated more than slightly below the long-term average. I can't recall when I last did that... .

How many will go around 12.5c. ??? 

How many will go around 12.5c. ??? 

Big news!

I estimated more than slightly below the long-term average. I can't recall when I last did that... .

Big shout that after months above average. I went the other way. Hmmm 

Met Office Hadley           13.4c.       Anomaly     1.1c. Provisional to 1st.

Metcheck                        10.73c      Anomaly     0.42c

Netweather                     13.76c      Anomaly     2.9c

I think we are long overdue a cold October with the cet significantly below average,sub 10c at least.The past few Octobers have been consistently warm.IMBY frost in October is a distant memory and have noticed in recent years the trees are turning later and later and major leaf fall now does not occur until 2nd half of November/early December.

I think we are long overdue a cold October with the cet significantly below average,sub 10c at least.The past few Octobers have been consistently warm.IMBY frost in October is a distant memory and have noticed in recent years the trees are turning later and later and major leaf fall now does not occur until 2nd half of November/early December.

Met Office Hadley          11.0c.        Anomaly         -1.2c. Provisional to 2nd.

Metcheck                        9.60c        Anomaly         -0.91c

Netweather                     10.78       Anomaly          0.38c 

Peasedown St John          12.25       Anomaly          0.25c. 

Met Office Hadley            10.0c.         Anomaly        -2.2c.  Provisional to 3rd.

Metcheck                         9.9c            Anomaly        -0.56c

Netweather                      10.1c          Anomaly        -0.31c

Peasedown St John            11.6c          Anomaly        -0.4c.       

I think we are long overdue a cold October with the cet significantly below average,sub 10c at least.The past few Octobers have been consistently warm.IMBY frost in October is a distant memory and have noticed in recent years the trees are turning later and later and major leaf fall now does not occur until 2nd half of November/early December.

I'll welcome a cold month at any time from now on, as long as that then doesn't end up being "it" for our winter.

Met Office Hadley             10.4c.        Anomaly       -1.8c. Provisional to 4th.

Metcheck                          10.43c       Anomaly       -0.08c.

Netweather                       10.82c       Anomaly        0.43c

Peasedown St John            11.2c         Anomaly        -0.8c.   

Met Office Hadley          10.8c.        Anomaly          -1.4c  Provisional to 5th.

Metcheck                       10.80c        Anomaly          0.28c

Netweather                    11.19c        Anomaly          0.79c

Peasedown St John         11.8c         Anomaly         -0.2c

Latest tracker for October. After a couple of very cold days last week it is generally looking slightly above average for the foreseeable future. Mainly due to relatively mild nights I think.

By 20th the CET is estimated to be at 11.61C.

Chart 1

Chart 2

October predictions table will follow on Monday evening. I don't have any more time today.

There's been a bit of a westward shift in the mean position of the N. Atlantic trough next week, enough to keep the flow more from the southwest rather than allowing it to turn to the northwest.

It's enough to keep temps very close to average overall, as mild nights offset cool days - much as GW surmised. 

In the FV3 12z, not much changes for the following week either, with my rough CET estimate landing bang on average as of 22nd (to within 100th of a degree Celsius... not that this means anything, it's just quite the happening!).

Overall, the signals are difficult to discern for the 2nd half of Oct. The atmosphere isn't fully committing to either a Nina or a Nino-like regime, leaving is in a pattern that would usually be very benign for more than just temps, but isn't proving so for rain & wind due to the N. Atlantic troughs proving unusually large & intense (even for October). This may be linked to the exceptional warmth in the North Pacific Ocean.

It doesn't bode well for our winter. Long-range modelling suggests we either get hammered 2013-14 style, or snooze under unusually strong & persistent areas of high pressure as the LP track sets up anomalously west of usual.

Met Office Hadley            11.3c.       Anomaly        -1.0c. Provisional to 6th.

Metcheck                         10.97c      Anomaly        0.46c

Netweather                      11.48c      Anomaly        1.09c

Peasedown St John           11.56c.     Anomaly        -0.44c    

CET competition predictions - October

Here is the prediction table for October

Provided the CET is 11.03C or lower, Col will retain his lead.

If the CET is at or above 11.04C then GezM takes over at the top of the table, albeit only by a margin of 0.03C at most.

If the CET is 11.60C or more then Dingle Rob squeezes into second place and we would have a spread of just 0.03C between the top three in the table. 

So it looks like things could get even tighter at the top this month. Best outcome for Col is a CET at or below his prediction of 10.85C which gives him an increased lead of 0.37C.

I am itching to make a prediction with a big deviation from the mean. But like September I just don't see that happening this month. Looks very average once again. Hopefully November and December will bring greater opportunities.

Link to full sized table

Good luck guys!  It’s a really exciting competition with the top runners so close!  

At this stage I’m not confident with my 10.8c guess.  We seem to be stuck in a mild, damp spell under night time cloud, rather than the crisp bright weather I’d hoped for.  But it could all change, as our fickle weather so often does!   

Good luck guys!  It’s a really exciting competition with the top runners so close!  

At this stage I’m not confident with my 10.8c guess.  We seem to be stuck in a mild, damp spell under night time cloud, rather than the crisp bright weather I’d hoped for.  But it could all change, as our fickle weather so often does!   

I'm perfectly happy with my 10.85C prediction. Of course it's still early days yet but there is nothing in any of the output I've seen that suggests anything significantly deviating from an average month. Naturally the figure will be running rather above the monthly average during the 1st half of October but as the LTA falls so quickly during the month then assuming generally average conditions contine that will bring it back in.  I think for October watching the anomaly is a better guide than the actual figure.