Apologies for the delay - been rather busy in the past week.
A rather cool September. Would have been much cooler had it not been for a milder spell in the final week of the month.
Please post your CET predictions for October in this thread. Entries can be made until 23:59 on the 3rd (Tuesday evening) without penalty.
Historic summary for October
1971-2000 10.4C
1981-2010 10.7C
1997-2016 11.1C
2016 was an average October at 10.9C. There have been several warm Octobers in recent years with 2005, 2006, 2011, 2013 and 2014 all at 12.5C or above. 2008 and 2012 both saw 9.7C which was quite chilly. 2003 was the coldest in recent years with 9.2C.
Here is a chart of the October CET for all years since 1961:
Current model output
850's showing something of an upward spike in the first week of September based on the op runs followed by something a bit cooler. But the ENS show a different story - massive scatter. So difficult to say what we might see in the first half of September.
GFS - huge scatter
http://www.wetterzentrale.de/de/show_diagrams.php?model=gfs&var=2&geoid=1140&lid=ENS&bw=
GEM - also huge scatter
http://www.wetterzentrale.de/de/show_diagrams.php?model=gem&var=2&geoid=1140&lid=ENS&bw=
ECM - a gradual cooling trend
https://meteoijsselmuiden.nl/knmipluim
Multi op - shows a sine wave pattern suggesting generally unsettled conditions
http://www.wetterzentrale.de/de/show_diagrams.php?model=multi&var=2&geoid=1140&lid=OP&bw=
Met Office contingency planners outlook
Not yet available
Pattern Matching - JFF
Well interestingly the CET for the last 3 months is a very close match to 2010. Another good match for the last 2 months is 2007. Another match is 1992 as is 1987 and 1967.
The final 3 months of the year saw the following for the years mentioned above:
1967 - average October, cold November and December
1987 - cold October, average November and December
1992 - cold October, average November and cold December
2007 - all months close to average
2010 - average October, cold November and December
What is interesting about the 5 years above is there was not a single year with a warm month in the final 3 months. All were either average or cold. So after a very warm first half of 2017 I think we could see a much cooler second half with potentially a quite cool end to the year.
Latest CET tracker prediction for October
Looks close to average overall but most days slightly below after a warmish start
