I’ve been banging on for days now about how temperatures are expected to cool down towards the end of the week after a brief warmer period over the next couple of days. I’ve decided to write up a Model Analysis to look at what the different models are predicting and how things might develop from here on in.
I’d like to start with the GFS Ensembles, a few days ago the operational run was very much on it’s own with forecasting this colder period of weather leading many, including myself to believe it was unlikely, however over the last couple of days the ensemble members have begun to show support for the colder outlook and you can see the remarkable temperature drop at 850hPa being forecast on the chart below.
The ECM model does bring in some colder air, however it’s not quite as potent as the GFS is showing with High Pressure remaining a little too close to the United Kingdom deflecting the coldest air East of the United Kingdom and eventually mixes out the colder air with milder air from within the circulation of the High Pressure.
The UKMO model, which worth noting is currently top in the verification Stats is more similar to the GFS than that of the ECM though it does differ slightly in regards to the position of High Pressure as you would expect, however even this model brings in colder weather across the UK.
The models over the last few days have varied somewhat with each output but the overall trend towards colder conditions has remained throughout with minor upgrades noticeable too, with this in mind, wintry showers are likely to effect higher levels of the North and East towards the end of the week, particularly so across higher ground but also down to lower levels too I expect.
Further South frost will be the main theme I think but I’m not ruling out the risk of some wintry showers here just yet, it would only take a small upgrade to bring the snow risk further Southwards and that’s something I think needs closely monitoring over the coming days.
Beyond this, into the weekend and into early next week things remain very uncertain, experience tells me that models are probably wanting to return the milder air a little too quickly at the moment so we could see the cold weather lasting for a little while longer than the models currently show.