MetService meteorologist Dan Corrigan said the forecast was for a "warmish", sunny start to the public holiday, but rain was expected to bounce in on Sunday and Monday.
So if you have any outdoor egg hunts or other activities planned for the long weekend, you are probably best to do it on Good Friday or Saturday.
He said a high pressure system was expected to move up the country tomorrow, bringing clear, sunny skies with morning frosts in inland areas.
There would be more frosts on Saturday morning, before temperatures rise as high as 18degC.
"The temperatures during the day time will definitely bounce back with a bit of sunshine ... They will be largely average for this time of year, throughout Saturday, Sunday and Monday."
However, he said rain was expected to arrive during Sunday, courtesy of a low-pressure system moving south down the country.
"It gets kind of muddy as we go into Sunday because it depends exactly where this low-pressure system is tracking and how intense it is going over the North Island, as to exactly what the impacts for the South Island will be.
"The rain may arrive in Otago and Southland later in the day, but it’s hard to pin down exactly when, at the moment.
"The forecast at the moment, shows occasional rain for Sunday - it may be quite brief as it just glances past."
Over Sunday night and Monday morning, he said there would be a southeasterly wind flow which would push rain onshore.
"It’s looking to make Monday and Tuesday pretty wet. I’d plan for a rainy day on the later part of Sunday and on Monday.
"The best day for the Easter egg hunts would be earlier in the weekend."
Because of the rain, he urged drivers to take extra care when driving home from holiday destinations on Monday.
"When the roads are busy, you can get poor visibility in heavy rain, and especially after a long weekend when people are feeling tired.
"It’s definitely a good reason to take care on the road."
