SSEN's Weather Watch for January 2021
Data from the UK weather stations from the Met Office shows the year 2020 was the third warmest year in records dating back to 1884, beaten only by 2014 and 2006, and it was marginally warmer than 2011. It was also provisionally the sixth wettest year for the UK in records back to 1862, and the 8th sunniest year since 1919.
The UK Met Office maps in the image above show the departure from the 30 year average for the mean temperature and sunshine duration. The south east corner of Great Britain was notably warm and sunny in 2020.
There was a white Christmas in a few regions, with parts of Suffolk, Cambridgeshire, Yorkshire and Northumberland seeing snowfall on the 25 December. Meanwhile, Writtle in Essex had its wettest December in 87 years, while Cardiff also had a wet month with its wettest December in 72 years.
The first week of January 2021 has started cold with below average temperatures. The cold weather extends across much of western Europe but the coldest country, relative to average, so far in January has been Spain. The first 10 days of the month will be the coldest and driest period with wind speeds also below average. It’s this part of the month we’re likely to see frost, ice and some snow too.
However, we’re expecting a change in the weather to take place during the week commencing 11 January. We will lose the north or north easterly breeze and instead the winds will come in from the nearby Atlantic Ocean.
This is a milder direction for Ireland and the UK and we should notice a fairly significant temperature rise in all parts. For example in Glasgow, daily high temperatures of just 1 or 2 Celsius at the start of the month will rise to 7 degrees, with values reaching 10 Celsius in Dublin and London towards the middle of the month.
The MetDesk map on our summary page shows the pressure pattern for the period 14 to 21 January, where you can see the low pressure is centred in the Atlantic and the high pressure cell is over Spain.
This weather pattern will bring mainly cloudy skies and periods of rain, notably to parts of Wales and England, although all parts will see some rain from time to time. The frosts will disappear too with night time temperature values over the soils and fields holding several degrees above freezing. Little change is expected as we head towards the end of the month as the weather pattern should hold.
So it’s definitely looking like a month of two parts, with the first 10 days or so being cold with night frosts then turning considerably milder with spells of rain for the remainder of January.
We’ll return in a few weeks to see how the weather trends are looking for February.
For more weather information you can follow our meteorologist, Simon Cardy on twitter @weather_king.