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Electric blankets may get a break in the South this weekend.
Warm nights are on the horizon for much of the South Island, as a ridge of high pressure sitting over the country begins to drift away to the east.
However, MetService meteorologist Alwyn Bakker said it would bring an end to the relatively dry and settled conditions of late.
"As the ridge moves off, it’s allowing a low pressure centre to move in from the Tasman Sea.
"The low centre drags in warmer, moister air from the north, spreading cloud over Aotearoa this weekend, and bringing rain to most of the South Island."
He said a high pressure ridge would cling to the country today, keeping the country mostly dry with some low overnight temperatures.
"In parts of Canterbury, Otago and Southland, frosty or foggy starts are likely as temperatures dip below 2degC, and fog and low cloud will persist around lakes and in valleys due to the lack of wind and low sun angle.
"As the ridge moves away east, the South Island will get the first wash of warmer, moister air on Saturday.
"Cloud and showers over the West Coast will turn to rain, spreading to the rest of the South Island on Sunday."
The wet weather would hang around into the new working week, he said.
Overnight temperatures would be noticeably warmer as the warmer air spilled over the country.
Temperatures were only expected to drop to between 7degC and 9degC at night over the weekend in coastal Otago and Southland, and as low as 5degC inland.
Daytime temperatures could reach 15degC during the day.
"The increase in atmospheric moisture leads to more clouds, which trap heat near the ground at night," he said.
"However, the reverse is true during the day, as the clouds reflect the heat from the sun back into space."