KEY POINTS:
Yesterday may just have been the end of summer, because the forecasters predict rain and cloud from today.
Cold, windy weather is on the way for most of the country for most of the week.
MetService forecaster Oliver Druce said sun-lovers should have made the most of the warmer-than-usual weather because umbrellas and warmer clothing will be needed this week.
Some parts of the country will be hit by snow and heavy rain.
"Yesterday was the last of the golden weather. Rain is expected to swallow up most of New Zealand, with some heavy falls particularly in the northern half of the North Island."
Mr Druce said things were likely to deteriorate tomorrow and on Wednesday with strong cool westerly flows, gales in several areas and snowfalls in the South Island mountains.
"We are on the cusp of sliding out of summer into autumn. The North Island is going to be much cooler from Tuesday, with heavy rain expected on the west coast of both islands."
The change ends a week of warmer temperatures than usual for this time of year.
Gisborne, Napier, Hastings and Kawerau all hit 28C in the past few days, it was 26C for Auckland, Hamilton and Palmerston North, and Tauranga, Taupo and Wellington hovered around 22C.
Mr Druce said the service forecast only up to a week in advance so it was too early to say if the warm weather would return.
"We may see some sunny periods but it is unlikely we will enjoy the same weather we have in the past week."
