In analogue #9 for Autumn 2018, we looked at the Autumns that followed on from Junes with a QBO of -20 or less because June 2018 fell into that category of Junes. For analogue #10, we're doing a similar subject but this time on the Autumns that followed on from Julys with a QBO of -20 or less because July 2018 all fits into this category. In fact, July 2018's QBO of -29.10 was a record breaker with no other July since 1948 having as negative (so therefore easterly) a QBO during the month.
The Autumns that followed on from these Julys look quiet overall with not a lot going on but there lies some month to month variation that makes this reanalysis quite obsolete at some parts of the season.
The Septembers of these Autumns look very cold with blocking over the Arctic and out into the Atlantic. It'd be wet to the east of the UK but overall not soaking wet as the Atlantic is being blocked off but it would most certainly be cold. Of course this is September so we're not talking subzero temperatures during the day or anything but it'd be very cold relative to average (like daytime maxima struggling in the low teens on some or many days).
The Octobers look very anticyclonic and quiet with above average heights over top of us. There's also a lot of blocking over the Arctic which if the floodgates were to open to northerly winds, it would become very cold indeed, similar to September but as it is October, it would be even colder.
The Novembers look fairly quiet with above average heights (though weak) through the southern part of the British Isles from the Atlantic to Russia whilst there is below average heights over Iceland but also above average heights over the Arctic. Away from Scotland, November looks mainly dry but also mild. Quite a benign chart.
We'd be looking at a fairly average to cool Autumn temperature wise if the above charts were to verify but also rather quiet with not a lot taking place.