Cycles

I'd had a 'feeling in my bones' for a while that this might be a hard and early winter in Beijing. And so it proved last weekend, with a vile spell of fog, sleet, and overnight freezes right at the start of November.

But now I'm starting to wonder if my premonition of this cold snap was not based on contemporary warning signs (the early nip in the air in October, the chestnut vendors hitting the streets already), but on an unconscious recognition of what has been a fairly standard pattern over the past decade or so. The last time we had snow in early November was 2009. We also had snow at the start of November in 2003. And the record low temperatures for the first week of the month were in 2000. I couldn't remember offhand what 2006 had been like, but I just did a quick check in the Weather Underground archives, and, sure enough, in the second week of November temperatures suddenly plunged below freezing. In the intervening years, it hasn't usually started freezing until towards the end of the month, and the mean daily temperature in the first half of November has been 10-15 degrees Fahrenheit higher.

So, that's looking like a pretty solid repeating sequence: every third year, we get a shitty start to November. We must console ourselves that next year should be better.

[In fact, it looked to be cheering up quite a bit when I left on Tuesday.]