Flights in and out of Dublin airport have been suspended due to heavy snow in the area.
Operations were halted for 30 minutes at noon while the runway was being sprayed with de-icer. The decision was then taken to shut the airport until at least 5.00pm. The Dublin Airport Authority has since extended the suspension until 8am tomorrow morning.
Flights are being diverted to Shannon, Cork and Belfast.
Ryanair, Aer Lingus and Aer Arann earlier cancelled all flights out of Dublin airport tonight due to the conditions.
Huge queues formed at ticket desks this afternoon as would-be travellers whose flights were cancelled yesterday and today attempted to make alternative arrangements.
The authority has asked all passengers on cancelled flights to leave the airport and rebook online.
However, the airport is providing free wi-fi access and large numbers of people were trying to access their airline websites on laptops and phones in the coffee area upstairs in Terminal 1.
The departures area became claustrophobically crowded, particularly around the Ryanair and Aer Lingus ticket desks. DAA staff did their best to corral the queues but the numbers of people were just too great. Queues for check-in desks crossed each other and people mowed through each other with wheelie suitcases.
One woman was crying with frustration in one of the lengthy ticket-desk queues.
Upstairs in a calmer, quieter restaurant area, one man could be overheard chatting to the woman beside him: he was on 'day three' of his attempt to fly from Dublin.
Regular announcements informed staff that Aer Lingus had ceased all check-ins.
The airport authority announcements said the authority regretted the airport would be closed to all departing and arriving flights. Flights due into Dublin are either being diverted elsewhere or are being instructed to remain at their departure point.
While the airport was open for business this morning, a number of flights were delayed, in some cases due to disruption at airports abroad.
At 11am, the newly opened T2 was very quiet. Terminal 1 was much busier, with queues appearing no busier than might be expected for check-ins during Christmas week. Certainly, the queues were nothing like those seen during the disruption caused by the Icelandic volcano ash cloud in April this year.
Carla Creighton from Dublin and Pete Francis from Manchester spent about eight hours in the airport yesterday and were already at a boarding gate when their Ryanair flight was cancelled.
They decided to leave the airport due to the cold last night and said they had spent about €60 on taxis today and yesterday. They were hopeful of getting on a flight by lunchtime but said they would refuse to pay any money over and above what they had already spent on their cancelled flights.
By noon, it had started snowing heavily around the airport. Surrounding roads had earlier been gritted, but driving even on main roads nearby, including the Old Airport road from Santry and the N2 posed problems for motorists.