Met Eireann is warning of widespread frost and hazardous travelling conditions.
A yellow low temperature and ice warning is in place until 6pm, when it will be upgraded to an orange warning again until tomorrow morning.
Kerry County Council says the priority routes are driveable with caution this morning. However, all other roads in Kerry have reports of frozen patches of snow and water, and some have black ice.
The council says untreated local roads, particularly in the Northeast and East Kerry, where lying snow persists, will be very hazardous after the hard freeze.
The plummeting temperatures are also having a serious impact on farmers.
IFA Munster Regional Chair Conor O’Leary says access to water for live stock is a particular challenge: