SSEN's Weather Watch for October 2017
Apart from a few local exceptions, September was cooler, wetter and windier than average across the UK – and sunshine levels were below average, notably in Wales with 80% of the 1981-2010 levels recorded.
September will also be remembered for the most active calendar month for hurricane activity in the Atlantic (due to hurricanes Irma, Jose, Katia, Lee and Maria). One factor which contributed was the persistently warmer than average sea surface temperatures in the tropical Atlantic this season as seen in P Klotzbach's chart above.
Back home, October has began particularly windy. This has been good news for the wind farms, as the highest recorded GB wind power was observed on the 1 October. Also, the National Grid has confirmed Summer 2017 as the “greenest ever”, with almost 52% of our power met by low carbon sources.
The big question is, is the unsettled, changeable weather going to last through October? The short answer is 'Yes'. We expect an active jet stream across the Atlantic in the next couple of weeks, and this will drive areas of low pressure towards north west Europe. So the weather maps will show frequent depressions in our patch of the world, with the high pressure mostly staying to the southwest of the UK.
A good example is noted from the weather model (on our main news page) for the period 14 - 18 October, showing the average positions of the low and high pressure systems. The low pressure is anchored near Iceland and the high pressure is established near the Azores. Typically, for this time of year, this gives us a prolonged period of windy weather, with above average rainfall for places like north Wales, Lancashire and Cumbria, and large parts of western Scotland. Temperatures will fluctuate near average levels for us, but it is likely to be warmer than normal for eastern Europe, and colder around the Alps.
To summarise for the UK and Ireland, we can expect October to outturn windier and wetter than average, with near, occasionally below, average temperatures and sunshine levels.
You can keep up to date with any Weather Warnings from the Met Office (https://www.metoffice.gov.uk/public/weather/warnings) and Met Éireann (http://www.met.ie/nationalwarnings/)
For more weather information you can follow our senior meteorologist, Simon Cardy on twitter @weather_king