I wrote an article a couple of days ago dismissing the chances of any prolonged cold weather, and low and behold in recent days models have started to become more consistent with bringing much colder, and potentially snowier weather to the United Kingdom during the second part of the month, currently, we’re keeping an eye on the period 19th – 28th January.
The key date at the moment is the 19th January, this is when the models tend to divert and begin showing different outcomes which is making this period very hard to forecast, for the last couple of days the ECM has been forecasting cold weather coming in from the East fairly consistently with new support from “lesser” models, the GFS however has also been fairly consistent in modelling a less cold, but more unsettled pattern during the period, the UKMO has been more of a half way house with cooler weather, but not as cold as the ECM, due to this, we’ll be focusing on the 18th in the charts below.
All three of the above models are for the same time frame, the UKMO and ECM are fairly similar in their evolution and positioning, whilst the GFS is fairly out on it’s own with a more pronounced Azores High. The lesser models are also more in line with the ECM in delivering colder weather to the United Kingdom.
So whilst this is a fairly difficult period to forecast with the huge differences in the short term between some of the models, there is an increasing trend towards colder weather with the strong consistency of the ECM, the slight trending of the UKMO towards the ECM and indeed, other models also now supporting a colder trend. I do think however it’ll be a good few days yet before the models come to any agreement/solution for beyond the 19th.
Forecast For Period: 14th-18th January
Under slack winds and a weak area of Low Pressure, temperatures will fall giving hard night time frosts, particularly across central areas with stubborn mist and fog during the mornings, this colder weather will last until roughly Tuesday before seeing a brief milder period. Highs of 6c early in the period, rising to 10c towards the end of this period as winds switch to a Westerly.
Forecast for Period: 19th – 24th January
An area of Low Pressure passing to the North of Scotland will switch winds round to a more North-Westerly direction once again bringing temperatures down to the seasonal average, perhaps slightly below in the North very early on in this period. This period now becomes very uncertain, between the 20-21st, Low Pressure looks likely to undercut a weak area of High Pressure developing to our North and this will begin to draw in much cooler weather from the East, however due to conflicting model outputs, confidence on this is low. One possible outcome is more much colder, Easterly winds to develop perhaps giving some areas their first snow flurries, another possible outcome is for Low Pressure to push away the weak High to our North, giving us a continuation of cooler, unsettled weather, again, confidence is low during this forecast period with two possible outcomes.