December 1874 CET was -0.2

Jan 1875 was 6.4

There have been plenty of Decembers colder than the following January but I wonder from the records how many extremely cold Decembers have turned into extremely mild Januaries.

I suppose it is not that unusual for a cold December to be followed by a mild January. After all, January is the month when under our usual weather patterns, the NAO turns very positive and the Polar Vortex ramps up to maximum strength.

Indeed, as far as I can recall from personal experience, January can often be the mildest winter month in the British Isles.

Those rare January's when we are put into the freezer are all the more precious for that very reason.

I suppose it was the extreme nature of the reversal* that caught my interest. The difference would be like 18.6C June followed by a 12.0C July.

* i.e. from the norm in terms of mean temps.

An article I wrote on that winter

http://www.ukweatherworld.co.uk/forum/index.php?/topic/49199-the-very-strange-winter-of-1874-75/

Interesting posts in reply to your 2011 post on another site- one that I didn't know about until now. What were the other strange years you alluded to?

1817, one of the strangest if not THE strangest year in the CET listings. That would be a year I would like to experience just for how odd it was.

Yes- got it. An amazing year- Feb the same CET as October, (how unlikely is that?)- such a cold May and October and June being the warmest month.

You are the weather oracle