This blog post is going to be about the fifth analogue for Winter 2018-19 and it's going to be on Winters that were preceded by cold Marches. This analogue was suggested by @joe_power3 on Twitter.
The 500mb height anomaly reanalysis from NOAA with these Winters shows a blocking area of high pressure over Greenland and Iceland. There is a trough of below average heights over the majority of Europe and some of that is getting up to the UK and Ireland. These below average heights provide the moisture for snow and it's most certainly a snowy and cold reanalysis, perhaps even exceptionally cold. The mean wind direction would be a northerly to northeasterly and is very December 2010-esque. I was very surprised with this reanalysis because when I originally thought of cold Marches, I could have sworn the results would be very mixed. For instance, March 1962 was followed by Winter 1962-63, the coldest Winter of the 20th century but March 2013 was followed by Winter 2013-14, the wettest Winter on record.
This is the December 2010 500mb height anomaly reanalysis as a comparison.
Looking at the individual Winters, there is mixed results after all especially for December which has a mean bang on the 1981-2010 average with these Winters combined. There are some freezing cold Winters like 1962-63 and 1916-17 in there (also to some degree, 1955-56 and 1985-86). Seeing this, it is strange how the 500mb height anomaly reanalysis turns out like it does. I'd also like to add that these are cold Marches based on the UK mean temperature, there would be rather different years for the Central England Temperature or Ireland if I were to do them. For instance, March 2010 would be one that is not in there which was of course followed by December 2010 which has a very similar reanalysis to the analogue. I guess you could also say that some of these years had high solar activity like 1947-48 so they're not good matches to 2018-19 which will be the solar minimum Winter going into solar cycle 25. We'll be getting down to details like that come a few weeks when we'll have produced preliminary analogues based on the elements we did like this one on cold Marches. I will be including the years that have come into our analogues at least 5 times.