TEMPERATURES AS low as -5 degrees are expected tonight, marking the start of a cold snap of at least a week.
The air temperatures would get “very cold” in a gradual progression, Met Éireann forecaster Joan Blackburn said. The sub-zero temperatures are expected to continue until the end of next week at least.
The cold spell is being caused by high pressure over Iceland and low pressure down south. This is feeding cold air in over Ireland, Ms Blackburn said.
Temperatures this low were “a little unusual” for November, but not exceptional for winter time, Ms Blackburn added.
Night-time temperatures will be particularly low and ground temperatures could reach as low as minus 10 in some areas. Snow is forecast for north Leinster and Ulster tonight, with sleet expected for Connacht and Munster. This band of snow will move south tomorrow and be replaced by icy conditions.
However, over the weekend and into next week, there may be snow showers coming in from the east. They would be intermittent, particularly in the north and east of the country.
The icy conditions expected as a result of low temperatures have prompted warnings from AA Roadwatch for drivers to take care. The organisation has urged caution, especially in the mornings, when frost, ice and freezing fog are expected.
“On these dark mornings, roads often refreeze around 7.30am or 8am and the number of crashes usually increases,” said Nicola Hudson, AA Roadwatch controller.
“Motorists should take particular care when driving overnight and in the early hours of the morning.” she said.
“With very low temperatures and frost forecast, it is likely that road conditions will be very dangerous,” Ms Hudson said. Motorists were also warned to watch out for black ice on all roads, particularly in sheltered areas.
Black ice is caused when drops of mist or rain freeze on the road. Ms Hudson said it was transparent and very hazardous.
Motorists were advised to allow extra time for all trips. “Road temperatures are often far lower than the air temperature and often drivers may not realise the roads are still icy,” she said.
The organisation is advising drivers to check that their tyres are in a good condition and properly inflated.
Freezing fog is likely to most frequent in Munster, around Tipperary, Cork and Limerick, as well as on the M7 motorway through Kildare and Laois and on the M1 motorway in Co Louth.
“National primary roads will be the first to be treated but even roads that are used regularly can be badly affected,” she said.