Mild Start To November
By Paul Homewood
It won’t have gone unnoticed for British readers that it has been an unusually mild start to the month.
I’m surprised the usual suspects have not blamed it on global warming or melting Arctic ice (though I may have missed it of course!) The reality is rather more mundane, as the Met Office’s 3-month outlook explained.
The cooling of the North Atlantic is indeed becoming markedly pronounced now, certainly in comparison with the slightly warmer than average waters to the south.
This strengthened temperature gradient is the total opposite of what is predicted by the polar amplification theory, which assumes that the higher latitudes will warm faster than lower ones.
As well as setting up a westerly wind flow, this gradient also has the effect of speeding up the jetstream, which means that temperatures of the air reaching the UK are warmer still.
UK Weather Scientific has a good explanation of what has been going on here.
Temperatures so far this month are by no means unprecedented, as November 1938 started in very similar fashion:
1938 also experienced similar airflow, which brought with it a run of depressions. One of these blew gusts of 98 mph into the Hebrides, well above Abigail’s 84 mph yesterday.
The weather turned markedly cooler after the 19th that year, and there are indications that the same will happen next weekend. All in all, the similarities between the two years are striking.
It is perhaps just another reminder that there is nothing unprecedented when it comes to weather.