A heavy snow watch is in place for the Canterbury High Country with a front expected to move up the South Island, while there is a heavy rain watch for central areas because of a trough.
Snow is forecast tomorrow night to 500 metres in the Canterbury High Country south of the Rangitata River, with significant snow above 700m that may approach warning amounts.
A low is expected to develop northwest of Taranaki overnight Wednesday, then deepen and move slowly towards Taranaki on Thursday.
A heavy rain watch is in place for Wellington, Kapiti Coast and Horowhenua, Mount Taranaki, the Marlborough Sounds and Richmond Range.
The warning for Marlborough Sounds and Richmond Range from Wednesday afternoon for 10 hours.
For Wellington, Kapiti Coast and Horowhenua as Mt Taranaki, the warnings are from Wednesday at 11pm.
Rainfall may approach warning criteria in all areas.