Temperatures are expected to reach 30C in Napier on Saturday, with a high of 29C in Hastings, according to James.
"Sunday will be much more bearable. You can expect 22 degrees, with overnight lows of about 10 to 12 degrees depending on where you are in the region.
"Then, it'll return to the mid to high-20s, with overnight lows of 14 degrees into next week."
Hawke's Bay Federated Farmers president Jim Galloway said farmers around the region
"For some who are in the normal summer dry area, it is nothing too unusual," he said.
"But for others up under the ranges where it is a lot dryer than it usually is and haven't planned for the dry so much it is getting tough.
"It is very tough for those who have had their water irrigation stopped. Not only for growing grass and crops, but also for things like washing down the cow sheds – they have restricted on how much water they can use."
James added that despite a southerly that will reach Hawke's Bay late on Saturday, MetService are expecting "a string of fine and calm days with not much in the way of rainfall".
Galloway advised farmers to "make decisions early on" and warned those who have to reduce stocking rate to "reduce it early".
"It is all about pre-planning and thinking ahead," he said.
Hawke's Bay Fire Area Commander Ken Cooper also issued a warning to people to be sensible when it comes to fire.
"The next four to five days, we are heading into extreme conditions again. We're expecting very high temperatures and strong winds, which will cause us issues."
