Gardaí in Tipperary are warning drivers to slow down following sub-zero temperatures overnight.
The force says it’s important to take extra care as driving conditions particularly on minor roads remain challenging.
Many parts of the county are dealing with freezing fog and icy conditions.
A status orange low temperature and icy warning is in place in the Premier County until noon today while a yellow warning of the same weather conditions is in place until Friday.
Meanwhile the National Emergency Coordination Group will meet each day this week to review the situation.
Minister O Brien says schools would remain open and all services, including public transport would continue as normal.
However Dublin Airport is advising passengers to check their flight status in advance with your airline directly.
It follows a number of flights cancellations into London overnight due to the freezing conditions and snow in the Greater London area resulting in the closure of Stansted Airport.
A new status freezing fog warning is in place for Co. Tipperary and the rest of the country until midnight.
Met Éireann says severe frost, icy conditions and freezing fog are leading to hazardous travelling conditions today.
The forecaster said temperatures last night were between -1 and -5C in most places, with Athenry recording -7.2C.
There’s also a Status Yellow low temperature and ice warning for Ireland, valid until midday on Friday 16 December.
The Irish Met Office says there are increased risks to vulnerable members of the community.