Heavy rain watches are in place for Otago and Southland in coming days, as the regions' dry run looks set to end.
Temperatures reached 30 degrees in inland centres today, but could drop to half that by Wednesday as a cold front moves through.
MetService says the front is expected to move northwards across the South Island, bringing with it a strong and cool southwest flow.
The effects of this front will be felt from tomorrow afternoon.
The forecaster says heavy falls of rain are possible across Otago, and in Southland and parts of Westland.
"Rainfall amounts may approach warning criteria, especially in the east where the threshold for heavy rain is lower."
Another high is expected to move on to the South Island from Thursday onwards.
Rain or showers are expected to affect the east of the North Island during Thursday, and there is chance of warning amounts of rain affecting northern Hawke's Bay, including the Wairoa District.
