Overnight temperatures of -3 degrees celsius have led to treacherous road conditions Friday morning.
Black ice on some roads and packed snow on others has resulted in many minor crashes.
Gardai are advising motorists to take extreme care, slow down and only travel if necessary.
Particular care is needed on the following routes this morning:
N4 Boyle to Carrick on Shannon where a number of vehicles have left the road.
N4 Longford to Mullingar
Boyle to Ballymote where two cars went off the road overnight near Keash
R294 Boyle to Gurteeen is particularly bad.
Boyle to Frenchpark.
Boyle to Culfadda around Brislagh, Derryknockeran and Meenmore is treacherous and cars have left the road.
St Nathys College in Ballaghaderreen is closed Friday as a result of the weather conditions.