‘This cold spell is rubbish compared to what we used to get!’
Every winter when weather model hype builds expectation for many, often days in advance, the outcome never seems to quite match the hype.
This expectation among weather nerds is inflated even further when the tabloids cotton on and build anticipation further only for it all to end in a ‘damp squib’.
I’ve lost count of the number of times when excited enthusiasts proclaim that an incoming cold spell is going to last at least three weeks; the reality being that the intensity of the cold has gone after four or five days. Cold spells since 2008 often arrive as a ‘blob of cold air’ from the continent that eventually gets ‘warmed out’; it’s been a very long time since we had a cold spell that’s been fuelled by a continual feed of air off the continent.
To illustrate my point I had a look back at every cold spell in this area of suburban east London since 1960. I weeded out the feeble efforts of the last few years by only considering spells where the maximum didn’t exceed 2.8C. The results spanned from the most recent cold spell of February 2018 to the mammoth 31-day Siberian blast that began on Boxing Day 1962.
In another blog I remarked how similar the 2018 pattern was to February 1962. This cold spell began on the 26th and lasted 9 days. Some 7cm of snow fell, this drifting in the wind, possibly making it seem worse with only 4 hours of sunshine which would have maintained any snow cover.
One of the snowiest cold spells happened in February 2009, eight days after an SSW event that lead to a polar vortex split. This four day spell saw a total of 26cm of snow fall.
February 1991 was even snowier, the intense cold lasting some 11 days.
Looking at other February cold spells a 7-day spell occurred in 1985 about a month after an SSW event.
Overall the median length was 5 days with an average of 6cm of snow and 8hrs of sunshine.
*A survey of winters ranked for temperature and snow can be found here.