South Island residents preparing for the school holidays this weekend can expect a significant weather system bringing rain, strong winds, and a potential drop in temperatures, according to meteorologists.

The storm is expected to move northward across the South Island starting Saturday, delivering heavy rainfall and gale-force winds through the weekend. By Sunday, a shift in weather patterns will introduce colder conditions as Antarctic air moves in, leading to frost in inland regions from Sunday night into Monday.

MetService meteorologist Paris Marshall noted that rainfall will begin on the final school day and persist until Sunday before a low-pressure system settles to the west on Monday. This system is predicted to generate additional rain bands through Tuesday.

Snow is anticipated on elevated roads in Canterbury and Marlborough beginning Monday, with the possibility of fresh snowfall at ski fields. The ski season, which has seen limited snowfall so far, might benefit from this cold snap if forecasts hold, though Marshall emphasized the inherent uncertainty. She described the incoming southeast flow as generally favorable for mountainous areas.

Another MetService meteorologist, Jon Tunster, described the upcoming system as potentially bringing significant rain to parts of the country but noted that the precise location—whether on the eastern North Island or eastern South Island—remains uncertain.

This weather event follows a month marked by extremes. June concluded with heavy snow causing road closures across the central South Island, stranding motorists at points such as the Lindis Pass and leading to school closures in Otago and Southland. Earlier in the month, Christchurch recorded its warmest June day on record, reaching 25.1 degrees Celsius on June 21, surpassing a previous high set in 1988.

Despite these swings, the overall climate for June was neither the warmest nor the driest on record, Marshall said, although maximum temperatures were notably elevated. In contrast, May had been particularly dry, setting records at the Christchurch Botanic Gardens for the lowest monthly rainfall since records began in the 1860s.