Cold air is already producing frosty and icy conditions across the UK this weekend and the cold feel will continue well into next week with further cold Polar Continental air pushing in from the east initially, before the winds veer more westerly bringing a polar maritime air mass which will also be cold.
This will bring a risk of hard frosts overnight but as a front from the west bumps into this cold air we could see a few periods of snow, although there is no signal for significant snowfall as yet, with conditions looking generally drier. Looking further ahead and significant signals now point to a high risk of colder weather developing as we head into the Spring season, more on this can be found at the end of this article.
looking at the next few days then and later tonight (Sunday 4th Feb) conditions will remain dry across the region and with clear skies expected then temperatures will plummet overnight with -3 to -4 expected with values of -6 to -7 possible in rural locations.
So a cold start can be expected on Monday morning, likely frosty as well but it should be dry and bright for most and this will be the case for much of the day, although still feeling cold. It will be another cold night with a frost developing but cloud cover will push in at some point in association with a weather front, which may bring a spell of snow for the region during Tuesday morning. How much is still unclear as yet but all signals and values support snow even to low levels so certainly one to monitor.
This front will clear though and leave us with further clear spells through the afternoon and evening although one or two showers may push in from the NW. Overnight the temperatures will again drop below zero with values between -3 to -8, coldest in rural locations or where any snow may lie. Ice may also be an issue from the earlier precipitation.
Wednesday as it stands remains dry and bright with plenty of sunny spells throughout, however, it will remain cold and later on and overnight the next frontal system pushes in from the west, to bring another risk of snow. However, there remains significant uncertainty on how far east this front will push so further monitoring will be needed and further updates will be posted.
Here are the expected overnight temperatures for the newt few days.
As mentioned earlier we are seeing significant signals for a potentially cold end to winter/start to spring. Now you maybe thinking that is still a fair way off so how can we forecast this. Firstly any specifics of course are impossible to forecast that far out, however, its almost certain a SSW (Sudden Stratospheric Warming) event will occur in the next several days. Two out of three of these events produce cold weather across W Europe/UK so its not a given although the odds are stacked in favour of a colder pattern. What this event will do is generally weaken the westerlies and allow some form of blocking to develop across the N Atlantic, thus, stopping the normal westerly flow.
In fact this particular event will reverse the winds in the stratosphere to an easterly, this last occurred in Jan 2013 and the net result from that was the coldest March on record. The graph below shows all 21 members of the GEFS showing a dip in zonal westerly winds, so much so they actually reverse to an easterly.
The next image shows this warming in yellow and red colours, yet also shows this warming splitting the polar vortex into two lobes, which is likely to send cold air well into mid latitude areas such as Europe and America.
All this may seem a little technical to most but there is no doubt there are going to be some form of pattern changes upcoming later in the month which should bring not only drier than normal conditions but perhaps colder than normal conditions as well. Much to discuss in the coming weeks.