Solar minimum is not far away as solar activity is designated at very low levels and 2019 is expected to be the year of true solar minimum. Therefore, for analogue 3 of Autumn 2018, I have decided to look at solar activity and specifically Autumns that took place during solar minimum or just before solar minimum. When we look at every one of those Autumns since 1851, we get the 500mb height anomaly reanalysis below. It shows a blocking area of above average heights to the south of Greenland and to the west of Ireland with below average heights over France. This forces the wind to come in from a northeasterly direction. In September, northeasterly winds would be average to rather cool but once you get into November, they become bitterly cold as the air comes from either the Arctic or Siberia flooding into Scandinavia. This happened in November 2010 and November 1919 for example.
If the Summer SSTs around us of now were to continue to November, they would make for a snow maker machine as the cold air comes from the northeast. What would be interesting is if a Scandi High takes off in November this year, there haven't been too many examples in modern times of such. Only one I can actually think of is 1993.
I have also made this table of the Autumn CETs in the analogue above. The darker the blue, the colder the anomaly. The brighter the red, the warmer the anomaly. The diff. column is the difference from the 1981-2010 averages. Quite scary honestly to see 1878 in there which contained one of the coldest Novembers on record, one of the coldest Winters on record (and exceptionally snowy too) and was followed by one of the coldest years on record in 1879 with not a single month warmer than average even by standards back then.
This analogue is quite different to the previous two although while the first one on warm Junes was unsettled, they were on the cool side.
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