Another day, another analogue. We previously looked at Winters following warm Junes as an analogue for Winter 2018-19 due to the fact that June 2018 was a very warm month. Now this time, we'll be looking at the Winters that followed on from very dry Junes because June 2018 was not only very warm, it was also very dry and anticyclonic.
Here is the 500mb height anomaly reanalysis of the Winters that followed the top 20 driest Junes on record since 1910 (apart from 2018 obviously). There is blocking over Greenland and stretching back into Siberia (though weaker over there) with a trough over much of Europe. The trough is centred over Biscay and Iberia but it looks like a knife edge to me between very cold and snowy or very wet and windy. I'd think it looks like that because we have Winters like 2010-11 and 1988-89 which were very different to each other.
The temperature anomalies reanalysis show average temperatures over us proving my point above BUT notice the warm pool over Greenland and the very deep cold pool to the northeast of Europe including over Scandinavia? The warm pool over Greenland shows the blocking which the 500mb height anomaly reanalysis has. If we were to tap into that cold pool over Scandinavia, it'd be a very cold Winter indeed.
Here's the table of Winters following very dry Junes. It again only proves my point of the 500mb height anomaly reanalysis being a knife edge between mild, wet and windy or cold and snowy. You can see this clearly in the table below like 1988-89 vs 1962-63. Deviations are from 1981-2010 CET averages. The darker the blue, the colder the anomaly. The brighter the red, the warmer the anomaly.
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