asked the Minister for Education if it is in order for national schools to close because of weather conditions.

The closing of a national school owing to adverse weather conditions or other exceptional cause is a matter for decision by the management authority which, under the Rules for National Schools, is charged with the direct government of the school. It is not abnormal for a management authority to close a school because of weather conditions which make it impossible, or dangerous, for the pupils to attend school, and such closures are sanctioned by the Department.

Is there any limit on the number of days on which schools may be closed in this fashion during the year?

There are 184 days de rigueur for opening. If it is outside 184 days there is no trouble. I am not aware of any specific fixed limit in the event of a snow storm lasting three months. I do not know. I do not believe there is any fixed limit.