March is the first month of meteorological spring. But what is the outlook for the month? Are we likely to get more spring-like weather, or perhaps something more reminiscent of winter?
The outlook suggests that March 2023 is more likely to be colder than average. But what is that likely to mean in terms of impacts?
From what we know so far – looking at some of the global drivers of weather – there are increased chances of impacts from cold weather, such as snow, frost and fog, at least for parts of the UK.
Mark Sidaway is a Deputy Chief Meteorologist with the Met Office. He said: "Although we have had a Sudden Stratospheric Warming event and other drivers pointing towards colder conditions in March, at this stage there is a low probability of having widely disruptive winter weather like that of five years ago in March 2018.
"At that time a large area of high pressure became established over Scandinavia, providing a feed of cold air all the way from Arctic Siberia. This brought intense cold to the UK.
"We are expecting an area of high pressure to become increasingly established in an area toward Greenland. This will allow a northerly flow to feed colder air into at least the northern and eastern half of the UK bringing wintry showers.
"The extended outlook shows the possibility for a series of areas of low pressure to come across the Atlantic, and these bring the potential for some more widespread snowfall as they encounter the cold air, although the location and timing of these is very uncertain for now.
"The exact positioning of the high pressure will be key and will greatly affect what weather we see in the UK."
March 2018 was a record-breaking cold spring, which had been driven by a feature known as Sudden Stratospheric Warming. This happens when air in the stratosphere above the North Pole collapses creating a disturbance of the Stratospheric Polar Vortex – where westerly winds rotate around the North Pole, effectively hemming in the most intense cold air.
When the Stratospheric Polar Vortex breaks down it can encourage the switching of normally westerly winds to an easterly direction. Eventually, this wind reversal can reach the surface, bringing air from an easterly source. In 2018 this resulted in intensely cold air coming to the UK all the way from Arctic Siberia.
Although the globe has experienced another Sudden Stratospheric Warming episode the outcome will not necessarily be a repeat of 2018.
What can we expect from early March?
There is a 20-30% chance that milder, cloudier, wetter and windier weather from the Atlantic will already be making inroads across the UK – with snow risk on the northern - leading edge - of systems as they come through.
The most likely scenario though is for colder and settled weather, with wintry showers perhaps affecting some northern and eastern areas (mainly coasts), at least at first.
This colder regime moving south across much of the UK, increasing risk of wintry showers, perhaps snow to the higher ground in the north. Temperatures are likely to be below average.
Beyond the first week or so of March confidence in the weather pattern becomes very low, but a preference for blocked broad scale conditions remains which continues to increase potential for colder conditions compared to average.
Spells of rain become more likely, with a chance that some areas could see snow. Some wintry episodes could be disruptive with a combination of snow and strong winds. North-west areas of the UK have the highest chance of remaining drier than average.
Temperatures are most likely to be below average overall during at least the first half of March. But values are expected to be nearer average overall later on. Within this, shorter colder spells remain possible.
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