Tongariro eruption: What you need to know

03:58, Nov 21 2012

* Airports are all open. Air New Zealand has issued a warning that flights might be disrupted and urged passengers to check its website for any delays or cancellations. Two flights between Wellington and Taupo have been cancelled. Wellington Airport spokesman Greg Thomas said the situation was being monitored.

* The Tongariro Crossing has been closed.

* Genesis Energy is shutting production at its Tongariro hydro scheme site south of Lake Taupo.

* Tongariro/Rangipo Prison, located near the base of Mt Tongariro, was operating as normal.

* A contingency plan has been put in place for the Lake Taupo Cycle Challenge, to be held at the weekend.

* Civil Defence has issued a national advisory for regions from Waikato down to Hawke's Bay, which could be affected by ash cloud.