Maximum temperatures around Napier are about 24C, dropping to 10C overnight.
Tuesday will get similar, albeit slightly lower, temperatures, and scattered rain.
"There's quite a nasty southerly coming into Wellington late on Monday.
"We see showers developing quite early in Hawke's Bay on Tuesday but they do clear south of Wairoa in the afternoon, and everywhere else by Tuesday evening."
The southwesterly change may cause strong gales in some exposed places, he warned.
Temperatures will dip on Tuesday, but won't be "cold by any stretch of the imagination", with a maximum of 19C and minimum of 8C overnight.
Best said temperatures would start to rise again on Thursday, and fine weather by Friday should last through the weeekend.
"It is looking nice on Saturday and Sunday."