Meteorologists are warning that the weather will take a dramatic turn in the next couple of weeks, as an El Niño is likely to be declared.

El Niño is a weather pattern that occurs when the ocean surface temperatures in the Pacific Ocean rise above normal levels.

It brings with it more frequent, dry westerly winds which heightens the risk of drought.

NIWA meteorologist Ben Noll expects one to be declared in the next couple of weeks.

He says the climate will change significantly.

"New Zealand is going to have more westerly winds than normal and westerly winds, they come from Australia, which can be a dry wind.

''It means the eastern part of both islands, with the likes of Gisborne, Hawke's Bay, Wairarapa, eastern Marlborough, Canterbury and parts of eastern Otago, these areas could start to dry out and maybe dry out quite quickly with rainfall looking considerably less than normal for this time of year in those regions."

He says while a drought is not imminent, it's likely.

''When you start to build or string together many weeks or months with reduced rainfall, that's when you can start to have those concerns about drought.

"At this point it is more about thinking ahead, if we do get many weeks or months of below normal rainfall, what that might mean for summer and of course that has implications on the agricultural sector, farmers, growers."

Ths El Niño will be one of the strongest Aotearoa has experienced in 80 years.

There has been five or six strong El Niño in that time, he says.

"The last one we had was in 2015/2016, before that you have to go back to about 1997 or 1998, there [were] a couple in the 80s and then one in 1972 and 1973."

Ben says the one that's building now is among those very strong El Niño episodes New Zealand has seen in the past.

"Some of those, such as the 1997, 1998 events, 1982, 1983, 1972, 1973 were associated with some of New Zealand's most significant drought events," he said

Fruit growers in Hawke's Bay have mixed feelings about the incoming weather.

Hawke's Bay Fruitgrowers' Association president Brydon Nisbet says the industry has been doing it tough over the past 18 months due to severe storms like Cyclone Gabrielle.

''The ground has been waterlogged and they haven't been able to operate properly. And in the last few weeks, a lot of that has dried out and it does look like we are coming into a dry spell. I think for growers, they're probably looking forward to something that's not so wet, but of course, with that dry, it will bring other problems and issues for us."

Brydon says the industry needs to start getting ready for the potential impacts.

"What growers need to do to prepare for this and it's what I am doing right now ... we've got to make sure our irrigation systems are running and are operational. A lot of our systems and dumps were damaged in the floods."

Ben says people should consider starting to conserve water.

-Delphine Herbet/RNZ.