There is a possibility of thunderstorms rumbling overhead during the day for most of the North Island this week. Photo / Susan Botting
Get used to a week of muggy nights and thunderstorms rumbling overhead during the day - muggy conditions are sticking around thanks to tropic-charged air enveloping the country.
MetService meteorologist Tom Adams said warm air was being dragged down from the tropics seeing scorching temperatures in eastern parts of the South Island while the upper North Island faced overnight lows that barely shifted from daytime highs.
As well, a threat of thunderstorms darkening North Island skies remained in place for the next seven days as a "procession of fronts" marched overhead.
"That thunderstorm risk is quite likely to continue into tomorrow and even a few around on Thursday possibly," he said.
"That will probably be one of the main things that people notice if they happen to be in the presence of one."
Today storms were forecast to strike across parts of Waikato and Bay of Plenty after midday.
Adams said there would be very warm temperatures across New Zealand with Ashburton expecting to reach 29C today and Auckland only dropping to 19C overnight.
Relief in the form of cool autumnal evenings would not come until next week.
"It is warm and muggy and sticky. In terms of any reprieve from that there's a little gap at the end of the week but it won't be until we get into next week that we start seeing a real decline in temperatures."
He described it as "diffuse" weather with cloudy conditions and scattered rain popping up over the North Island but hard to pin down to one area.
"It's a day where people, if they're planning to head outside or do some washing or anything with a weather-dependent element to it, just have a quick check on the rain radar before you do," Adams said.
The country had enjoyed a summer of settled weather but things were set to start moving again when we entered autumn and "that's exactly what we are seeing here".
"There's going to be a procession of fronts that move across the country and also some pretty convective conditions which means a risk of thunderstorms," said Adams.
"There could be thunderstorms popping up for the coming week, particularly in the upper North Island."
He said with thunderstorms it could be an "all or nothing" experience.
"If you're under it you might get heaps, if you're a kilometre away you might get nothing," he said.
In amongst the thunderstorms there would be "quite a few fronts" moving across the country.
"We really are seeing a ride through all the various different types of weather over the coming weeks whereas up until now things have been very static week-on-week.
"There's a very moist air mass over us right now. As we go into the weekend we could see a particularly moist air mass dragged over us. Depending on what the remains of a low from the tropics moving north of New Zealand does, it could drag some moisture down as well," he said.