He said the lower South Island is expected to be particularly hot and dry.
"South and west of Christchurch, including south Canterbury, Otago, Southland, the West Coast, we're watching for the potential of some periods of unusually dry weather which can lead to incredibly dry soils."
Otago rural principal fire officer Mark Mawhinney said the region has already been forced into action, any outdoor fires in Otago need to be first approved by Fire and Emergency NZ.
"We've based that around a number of fires recently that have scaped also there is an ongoing drying we are seeing in our landscape.
Mawhinney said some rain is predicted but it won't be enough to keep up with the summer drying that occurs.
Knowles said the climate is being driven by a La Nina weather system that is sitting above us in the tropical pacific ocean.
He said this will bring more rain for the North Island.
- RNZ