Met Éireann has issued a fresh yellow snow and ice warning for Donegal, valid until 6am on Friday, with temperatures are forecast to plunge as low as minus 6 degrees on Thursday night.
The forecaster predicted highs of between three and six degrees on Thursday afternoon before the onset of widespread frost, fog and ice overnight.
A yellow snow and ice warning from the UK Met Office remains in place for Antrim, Down, Fermanagh, Tyrone and Derry for all of Wednesday. It said “further snow showers and some ice are likely to continue to bring disruption to travel”.
[ Why has the weather been so cold?Opens in new window ]
In an updated statement on Thursday afternoon, the Northern Ireland department for infrastructure said only travel if the journey is “absolutely essential”.
“A Met Office warning for snow and ice remains in place with sub zero temperatures forecast throughout the day, however, due to industrial action only very limited gritting of the road network will take place today,” it said.
“As a result gritting which took place on Wednesday evening will no longer be effective, road conditions are likely to deteriorate and driving will become increasingly hazardous. While some gritting will be delivered today it will be confined to the main roads connecting our towns and cities at best.
“Much of the road network that would normally be gritted will not be treated and road users should be very mindful that conditions on the roads will be variable.
“Gritting will continue to take place on the M1 and M2 motorways, the A1 and the A4. However, road users are reminded that roads leading to the limited salted part of the network will not be treated so extreme caution will be required for anyone travelling on any part of the road network.
“Even where gritting has taken place the Department can never guarantee ice free roads due to potential wash-off from showers and the formation of black ice so please drive slowly and be prepared for changing conditions.”
The department added that pedestrians should equally take great care when walking on footpaths and the road network will also remain hazardous for travel on Friday, January 19th.
Elsewhere, it looks set to remain dry and sunny for much of the country, but scattered showers of rain, sleet and snow in the northwest will spread across Ulster and north Connacht through the afternoon and evening.
However, Met Éireann said that the cold conditions will begin to change from Friday with an increase in cloud cover causing temperatures to rise to between 4 to 7 degrees.
Rain will then spread throughout Friday night and by Saturday morning there will be more outbreaks of rain. It will be noticeably milder and windier than previous days with afternoon temperatures of 7 to 11 degrees.
Stormy conditions of heavy rain and very strong, gusty southerly winds will arrive by Sunday, Met Éireann said. However, temperatures will by then have increased to 11 to 13 degrees.
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