Temperatures in Hastings are set to plummet to freezing again overnight, a chilling reminder winter is just around the corner.
The brisk mornings will continue until the weekend when the system bringing the southwest chill moves east.
Mr Law said the weekend should warm up, with temperatures likely to reach 17C.
"A northwesterly flow will gradually spread up the country ahead of a weather front." The front is expected to approach the South Island on Friday then move up the North Island on Saturday and Sunday.
"Hawke's Bay is not a bad place to be at the moment," said Mr Law.
Other than the odd shower around the Cape and Mahia, the Bay would remain dry until late this week: "There is a chance of some high cloud and scattered showers on Sunday."
Monster waves pound Otago coast
Ten-metre waves, whipped up deep in subantarctic waters, crashed into the Otago coast yesterday, preventing ships from entering the harbour and giving Dunedin beach defences a good workout.
The giant waves were breaking behind and over White Island off St Clair Beach, although the Esplanade appeared to have stood up to an onslaught at high tide, shortly before noon.
Department of Conservation ranger Colin Facer said he had been working at Taiaroa Head for 16 or 17 years ''and that would be the highest [seas] I would have seen''.
That sentiment was shared by Port Otago chief pilot Captain Hugh Marshall, who said: ''That's probably about right.''
''What we're actually seeing on the coast today is the longer waves coming from well south of New Zealand.''
The low had moved, but the big waves generated days ago when the low was south of New Zealand were peaking yesterday morning.
''They're really grunty; they've got a lot of energy associated with them.''
Erosion at St Clair closed a walking track this week, but Dunedin City Council parks manager Lisa Wheeler said there were no reports of further damage yesterday.
Huge waves and powerful winds scattered debris and stopped traffic on coastal roads in Wellington yesterday, NZME reported.
In the South Island, high tides and big swells blocked parts of State Highway 1 in Kaikoura.