Update 10.39pm: The Irish Aviation Authority has reopened Irish airspace following the earlier radar failure.
Delays are expected for morning flights, however.
Some flights which were delayed by the radar systems failure will land at Shannon Airport tonight.
**UPDATED FLIGHT INFO**
Inbound to SNN:
•Ryanair FR1183 Gatwick - arrival time 23.25 ESTM
•Ryanair FR4776 Manchester - arrival due 22.45 EST
Outbound from SNN:
•Ryanair FR4777 to Manchester departure: 23.15 ESTM— Shannon Airport (@ShannonAirport) October 2, 2018
Update 9.19pm: A number of flights have been cancelled across the south and west of the country as a radar systems failure affected Irish airspace.
Cork Airport and Shannon Airport have seen flights cancelled due to a radar failure while Dublin Airport has not been affected.
"There is a significant systems failure with a radar in the west of Ireland resulting in a 'zero flow rate' in Irish aerospace at present," Cork Airport said in a statement.
"Dublin Airport is exempt due to proximity to UK air traffic control.
"Cork Airport apologizes for the obvious inconvenience this is causing."
The airport added that flights that were already in the air have landed.
"Anything already in the airspace was processed through or has landed but nothing else is allowed to enter this airspace at present."
Aer Lingus and Ryanair are among the airlines impacted by the air traffic issues. Arrivals and departures at both Cork and Shannon have been suspended.
Air Traffic Control at Ballcasey, Shannon are experiencing issues with their flight radar," Shannon Airport confirmed.
"Work underway to rectify the situation. Arrivals and Departures at SNN have been suspended until the radar is fully operational."
Passengers travelling through Cork Airport are urged to check the status of flights with their airline as many aircraft and crews are out of position tonight which may impact on flight operations tomorrow morning.
Please check the status of flights with your airline presently as many aircraft and crews are out of position tonight which may impact on flight operations tomorrow morning. pic.twitter.com/0CdgzsooJ1— Cork Airport (@CorkAirport) October 2, 2018