You would be forgiven in thinking this cold winter weather has finally been shifted this weekend as High Pressure builds in, temperatures look likely to recover to the dizzy heights of 5-7c across much of the country so if you do still have lying snow/ice this is expected to thaw this coming weekend. However as we move into next week current indications continue to suggest the colder weather will return.
At the moment High Pressure is developing over the United Kingdom and this will temporarily shift the colder air Eastwards and replace it with slightly milder air, though as we move through the weekend and into next week the area of High Pressure that brought us the less cold air will begin to build North-Westwards into the Atlantic and up towards Greenland, once again creating a block in the Atlantic and forcing colder air South and West across Europe and towards the UK.
Although colder air will begin to push across the United Kingdom early next week, the much colder air looks more likely to push in from around the 16th onwards as High Pressure really develops towards the North-West of the country, perhaps one of the more impressive blocks I’ve seen with a High Pressure cell reaching 1060MB which is really quite impressive. The models we’re seeing at the moment are supported by the teleconnections, the Arctic Oscillation is being forecasted to drop into a fairly deep negative and this suggests Low Pressure over the Arctic being replaced with High Pressure. You can see this indicated by the red lines on the chart below.
And finally, if we take a quick look at the GFS Computer Model Ensembles we can see that the mean (white line) drops below the -5c line from around the 14th December and beyond and when this happens, any precipitation that does fall will likely fall as snow.
So after a less cold weekend with temperatures recovering to around average for some areas, it will turn much colder as we move through into next week as high pressure pushes North-West into the Atlantic and towards Greenland bringing back the colder air from the North or East. The main question when cold is mentioned is “Will there be snow?” it’s looking likely that snowfall will return to the forecasts but how much and where is something that cannot be answered until closer to the time. But certainly the risk of snowfall does increase beyond 16th December and towards the Christmas period.