Fresh southerlies likely for months if El Nino hits, says expert

If you're feeling the cold and already anticipate the beginning of the Spring thaw you may have a long wait - a prominent weather analyst says a cool spring with more southerlies than usual is looking "very likely".

Climate scientist Jim Salinger of the World Meteorological Organisation said there was a more than 60 per cent chance of an El Nino weather pattern affecting New Zealand's weather for much of the rest of the year.

El Nino - unlike the warmer La Nina pattern of the last two years - tends to mean more southerly winds and cooler temperatures in the North Island.

The North Island's East Coast, Northland, Bay of Plenty, parts of Hawkes Bay, Nelson, Marlborough and north Canterbury tend to be drier when there is an El Nino - raising the risk of drought for farmers. Fiordland, Southland and Dunedin tend to be wetter.

Dr Salinger said the Pacific was already showing signs of a borderline El Nino weather pattern, with warmer water in the central and eastern Pacific Ocean and weaker Easterly winds.

Another indicator, the Southern Oscillation Index (a measure of atmospheric pressure difference), has plunged, also pointing to an El Nino.

Dr Salinger, who is president of the Commission for Agricultural Meteorology, said a weak to moderate El Nino was more than twice as probable as usual. "Normal" probability is 30 per cent. "It looks very likely."

"If you average out all the (climate) models they show El Nino conditions in late winter and for the rest of the year," he said.

Farmers could get a slow start to spring and should look out for droughts in some parts of New Zealand, he said. The last time New Zealand experienced El Nino conditions was autumn 2006, and that was for a brief period.

Dr Salinger said El Nino could cause drought in parts of Australia.

The Brisbane Times' website yesterday reported fears of El Nino water shortages in southern New South Wales and northern Victoria. Fiji's Ministry of Agriculture was taking steps to prepare for the possible impact of El Nino later this year.