Ireland braced for coldest weather since 2010 amid Arctic blast forecast

Ireland is braced for one of its coldest spells of winter since the big freeze of 2010 which saw temperatures here dip below -10 degrees.

Meteorologist Cathal Nolan from Ireland's Weather Channel, has said weather models indicate that a 'blocking pattern' may cause air from the Arctic to flow over Ireland within weeks.

In an update to followers, he said: "For many today marks a return to normal following the passing of the seasonal holidays, but our weather looks increasingly likely to be anything but normal as we progress into January.

"The two primary forecast models, the ECMWF and the GFS are both indicating the development of a blocking pattern synonymous with a negative NAO, which in itself is indicative of colder than average conditions during an Irish winter.

"A negative NAO, combined with an increasingly weak polar vortex, in part due to a Sudden Stratospheric Warming event in an El Niño winter, means that such a blocking pattern could indeed materialise and persist for a prolonged period of time.

"The transition towards a colder spell begins to occur through Thursday and Friday of this week as we see high pressure developing across the country, cutting off the Atlantic flow across much of Ireland, the UK and northwestern Europe.

"At present the location of the high pressure means that initially our weather would remain dry, sunny but much colder, with severe night frosts and ice likely. Though towards the end of the period the high could well slip farther to the northwest.

"Such a change would allow even colder air to feed down from the Arctic with an increased risk of snowfall in some areas. At present this blocking pattern is expected to continue deep into January, though as ever there are some caveats when looking so far ahead.

"What is clear is that our weather will turn much more settled, colder, but drier from Thursday/Friday onwards. If a blocking pattern develops it would likely turn out to be the coldest spell since 2010, though for now, significant uncertainties remain."

Meanwhile, Met Éireann are forecasting a dip in temperatures but have not looked this far ahead with any certainty.

Their outlook says that while things look like "turning more settled towards the end of the week with high pressure looking set to dominate," it will then be "turning cold also with frost, mist and fog likely."

By Friday night, temperatures will dip below zero with -1 possible while the national forecaster predicts temperatures as low as -2 next weekend.

"Our weather is likely to continue settled and cold as high pressure is expected to stick around into next week," they said.