A severe weather watch is in place with heavy rain expected to hit the North Island tonight and over the next two days.
The watch is in place for the Waikato, Waitomo, Taupo, Bay of Plenty and Rotorua regions.
''It's going to be damp and muggy and wet,'' MetService forecaster John Law said.
First rainfall is expected tonight with heavy rain forecast to hit Taupo on Tuesday and the Waikato and Bay of Plenty on Wednesday.
Hamilton will get its first dose of rain tonight with thunder storms and a top of 24 degrees Celsius forecast tomorrow.
The rain is expected to stick around until next Wednesday.
People are advised to keep up to date with the latest forecasts in case any of the areas in the watch are upgraded to warning level.