White Easter a possibility?
1st March, 2016
Sudden stratospheric warming ‘increases the risk of cold north easterlies and wintry weather for the UK over the next few weeks’, says the Met Office, as media outlets report that a ‘white Easter’ could be on its way.
The Met Office has issued a rare warning for a ‘sudden stratospheric warming’ event. Occurring every couple of years on average, sudden stratospheric warming triggered the Big Freeze in 2010, which saw the mercury plummet to a low of -22.3 C in the Scottish Highlands at its peak.
Professor Adam Scaife, the Met Office’s Head of Monthly to Decadal Prediction explained:
“Sudden stratospheric warming events occur high up in the atmosphere and involve a complete reversal of the high altitude polar jet stream – they can even affect weather at the surface, and for the UK a sudden stratospheric warming increases the risk of wintry weather.”
Sudden stratospheric warming occurs when air over the North Pole warms, causing high altitude winds in the jet stream to reverse and flow from east to west. As the Atlantic jet stream moves south, cold air from the east moves into the UK and other parts of northern Europe.
The Met Office has warned that this sudden stratospheric warming event is likely to cause a cold snap in late March and early April, with temperatures dropping to zero most nights and potentially snowy and icy conditions.
“The last big [sudden stratospheric warming] event was in early 2013 and was followed by a cold end to winter. Although the impact of the current event is unlikely to be as severe, it increases the risk of cold north easterlies and wintry weather for the UK over the next few weeks.”
This warning has led many media outlets to report that we will see a ‘white Easter’ this year. The date of Easter shifts every year as it is calculated by the cycle of the moon, meaning it can fall within a period of 35 days. The earliest Easter ever recorded was on March 22 in 1761 and 1818; this year it falls on March 27.
The Met Office say:
“If Easter is early, there’s a chance that some parts of the country will get snow; in fact, it is more likely to snow at Easter than it is at Christmas.”
Despite the increased likelihood of wintry conditions this Easter, the Met Office have stressed that long-range forecasts are not always accurate:
“At this stage it is too early to provide details about what the weather will bring for Easter. Beyond a week ahead we can’t say what will happen on specific days, but we can give an idea of what type of weather we can expect.”
Although the weather may be uncertain, the Met Office stress the importance of being prepared for extreme weather throughout the colder months:
“As always we are working with our customers such as EasyJet and other major airlines, airports such as Heathrow and Gatwick, local councils, and energy providers, together with government partners in Highways England and Transport Scotland to ensure they are prepared for the current wintry conditions and whatever the weather may bring in the coming weeks.”