Hot temperatures can be expected throughout New Zealand with all major centres heating up over 20C.
Auckland is in for a tropical 27C both days, Hamilton 28C, Tauranga a little cooler at 25C and Wellington 23C today and 24C tomorrow.
Christchurch and Blenheim are both tipped to be the hottest centres today reaching 31C.
According to WeatherWatch, those in the Kaimai Ranges between Bay of Plenty and Waikato may be affected by foggy patches.
The South Island will be mostly sunny throughout except coastal Southland where clouds and a few showers may remain.
Heavy rain is set to build in the Northland and Auckland areas and will continue to spread towards the central North Island. "We're looking at rain mostly developing overnight on Sunday and into Monday," the Metservice spokesman said.
The reason is an atmospheric high that has been sitting off the side of New Zealand blocking off the east.
The spokesman said despite the wet weather forecast for the end of the weekend it should be fine otherwise.
"Overall, the weekend is set to be muggy, humid and occasionally wet - but all in all not too bad. Mainly fine just the odd shower here and there," he said.
Despite a calm-weather weekend on the cards, it has been a wacky start to 2018.
Whether it be the extreme highs in the South Island or the storm surges in the North Island, insurance claims for weather-related losses are set to be high.
The last major storm caused widespread damage throughout the country after strong winds, high tides and heavy rain.
At the time the Insurance Council advised people affected by the extreme weather to contact their insurer as soon as possible.
Insurance Council chief executive Tim Grafton advised people to take pictures of the damage in order to help insurers in their claim assessment.
The council is still yet to tally up the total cost of the storm that caused a lot of localised damage to the Coromandel and Thames areas.
In December last year it announced that 2017 had been the most expensive year on record for weather-related losses.
Insurers put losses from the year's events, all of which hit in the first seven months, at $242 million - five times that of 2016's bill for extreme weather.
Remnants of Cyclone Debbie and the Port Hills fires were two events that featured insured losses of $91.5 million and $18.3 million respectively.
National weather outlook
• Whangarei: Cloudy periods with one or two showers. Northeasterlies. High: 27 degrees, Low: 20 degrees.
• Auckland: Cloudy periods with one or two showers. Northeasterlies. High: 27 degrees, Low: 20 degrees.
• Hamilton: Morning cloud clearing to mostly sunny. However, chance shower from afternoon. Light winds. High: 28 degrees, Low: 17 degrees.
• Tauranga: Morning cloud with one or two showers, then sunny spells. Northerly breezes. High: 25 degrees, Low: 20 degrees.
• Wellington: Sunny spells. Chance morning shower. Northerlies picking up morning. High: 23 degrees, Low: 18 degrees.
• Christchurch: A fine, hot day. However, low cloud coming in evening. Light winds. High: 31 degrees, Low: 16 degrees.
• Dunedin: Cloud increasing, one or two showers from afternoon. Light winds. High: 24 degrees, Low: 15 degrees.
• Queenstown: A fine day with some high cloud. Northeast dies out evening. High: 28 degrees, Low: 14 degrees.
