"A brief area of high pressure will cover New Zealand on Wednesday but later this week and into the weekend low pressure and rain looks again to be the main feature."
Northern and western regions would get the worst of it, however, the spokesperson said.
Thursday across the Bay will be overcast with showers developing and showers are forecast to continue, off and on, through Friday and into Saturday, although sunshine is forecast to return later on Saturday.
"Most of New Zealand is pretty wet right now - although some eastern areas may have a drier pattern if our weather continues to mainly come in from the Tasman Sea area and we get more westerly quarter winds."
Motorists travelling the region's highways are also being advised to be ready for minor delays as road maintenance programmes continue.
Minor delays due to temporary speed restrictions and stop-go signalling can be expected at several sites along State Highway 2 north between Napier and Wairoa.
Construction of a stock underpass on SH50 near Creek Rd and Gwavas Station will also result in slight delays.
Mr Postings said the major projects at the Whakatu arterial roundabout and the SH2/Watchman Rd intersection were progressing well.
"We are not noticing any significant delays in peoples' journeys through these sites."
● Winter Journeys webpage - www.nzta.govt.nz/winter-journeys