Tag Archives: NOAA

A mostly quiet and dry autumn on the way?

I don’t usually bother trying to forecast autumn or spring given that there is far less interest in them than winter and summer. However, given the heightened interest in this year’s hurricane season and emboldened, perhaps foolishly, by my reasonably correct summer forecast I decided to have a look at the stats and see if I can find any signs where autumn in east London may be headed.

Using the methsummer simsod for my seasonal forecasts resulted in a shortlist of 26 summers that were similar to 2016.

Because the NOAA ENSO index only goes back to the 1950 I decided to disregard all years prior to this date to try to make any results more reliable. This narrowed down the list to 11 years.

With these considered I then searched for years that had a similar ENSO index to June (0.1 – neutral) with a tendency to turn negative (La Nina). This narrowed the field further to three years: 1999, 1992 and 1964. However, the only year that is showing signs of being similar with regard to where the ENSO index is forecast to be heading is 1964.

Although, so far, there has been an uptick in hurricane activity similar to 1964 there is, of course, the added consideration that Saharan dust is playing a part in impeding the formation of these tropical storms in the Gulf of Mexico – something the weather models seem to struggle to get a grip on.

With this in mind perhaps there will also be lower than usual instances of these storms crossing the Atlantic to affect the UK: hence a quiet autumn though, on a national scale, interpersed with the odd interest from the Atlantic. weather notes 1964In London, perhaps we can expect something very similar to what is listed on the excellent website: http://www.london-weather.eu/article.103.html

autumn 1964

 

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A warm North Atlantic is cranking autumn into life

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On looking at NOAA’s sea surface temperature anomaly in the North Atlantic tonight there seems to be a lot of orange (warmer than usual) off the coast of Ireland across the pond to the US.
A lot of energy therefore has to be displaced before we can start thinking about any sustained cold weather – and is a big part of the reason why the Atlantic has kicked back into life.

The jet stream is centred over us
The jet stream is centred over us
Expect a succession of depressions, driven along by a brisk jet stream (currently right over us blowing at over 100knts) to whistle across us in the next 10 to 14 days bringing very mild temperatures together with a mix of rain, blustery winds and sunshine. Any HP ridges will probably be short-lived – though equally any rainfall should be average. In these situations most of the rain falls over western parts of the British Isles.

So, in summary, a changeable spell is coming up – just like autumn should be