La Nina is expected towards the end of the season, says Bureau of Meteorology | The transcontinental

There are mixed feelings about the prospect of a late-season La Nina weather event, with rain still welcome in the south, but not in the north of NSW and Queensland, where harvest has begun.

The Bureau of Meteorology (BOM) this week upgraded its La Nina tracker status to a La Nina alert, which means the probability of the event, which is correlated with above-average rainfall in much of Australia, has a probability of about 70 percent occurs.

This is roughly three times the normal odds of La Nina winning.

The Bureau made its assessment based on the continued cooling in the tropical Pacific Ocean and an increase in the number of climate models showing sustained La Nina conditions over the summer.

It reported that some atmospheric indicators such as the Southern Oscillation Index (SOI) and cloud cover near the date line are approaching La Nina levels.

Six of the seven international climate models examined by the Bureau will meet the La Nina criteria from November.

The weak dipole event in the Indian Ocean, also a trigger for above-average rainfall, will continue, but the BOM indicates that it will soon return to neutral levels.

Brett Hosking, chairman of Grain Growers, said the impact on the country’s projected 50 million tons plus winter crop is being closely monitored.

“In the south, you’d say most areas would benefit from rain for the next 14 days and some for up to a month, but in the north the harvest is already in full swing in the south to north of NSW, so growers not wanting too much “rain until they get their crops,” said Hosking.

He said that a wet crop is now the main concern of growers.

“We have passed the frost window in most areas, so the crop rain will be the greatest threat to both quality and yield if it gets really wet.”

“With such a good harvest and the high prices for practically all raw materials, farmers get nervous until the harvest is in the bin.”

However, he said there would also be farmers who would cheer the rain for their summer crops.

“Summer crops will look for some moisture, and even winter crops will welcome post-harvest rain that can help them develop a subsoil moisture profile for the 2022 season.”

“The bottom line is basically that people want a dry month or so while they harvest, but welcome rain at any other time if that’s not too fussy,” he said.