Australia, the world's fourth- largest wheat exporter, "urgently" needs rain in eastern grain regions as dry weather damages the chance of meeting a government forecast for the biggest crop in four years.

"Extremely hot conditions in northern New South Wales and Queensland over the weekend will have cut yield prospects," Luke Mathews, agri-commodity strategist with Commonwealth Bank of Australia, said today in an e-mailed report. "Widespread rain is urgently needed in those regions but no relief is in sight."

Farmers need rain now to reach yield potential in crops ahead of the harvest, which starts from about November. Should drought-causing El Nino weather conditions develop this year, wheat production in Australia's eastern states may drop by as much as 25 percent, Standard Chartered Plc said last month.

The two states planted the biggest area to winter crops in at least 14 years in autumn, putting the nation in line for the largest output since 2005-06, according to a June report from the Australian Bureau of Agricultural and Resource Economics.

Rain in New South Wales, usually the nation's second- largest grain grower, in the next 10-14 days is "critical," that state's government said yesterday. Without rain within two weeks some farmers will put livestock onto crops and won't harvest paddocks, the state's Primary Industries Minister Ian Macdonald said yesterday in a statement.

"The weekend heat will have a significant impact" on Queensland crops, said Lyndon Pfeffer, president of the grain unit of state farmer group, AgForce, in a phone interview. "Some are too far gone to save."

Fire Ban

Queensland, usually the nation's smallest mainland grain producer, banned all fires in southern parts of the state today amid forecasts for hot, dry and windy weather.

"These conditions would result in a very high fire to extreme fire danger in these areas, meaning the weather is perfect for bushfires to ignite and spread quickly," Queensland Fire and Rescue Service Commissioner Lee Johnson said in a statement on the government's Web site.

Much of eastern Australia had below-average rain in July and August, with conditions particularly dry in northern New South Wales and Queensland, the nation's weather forecaster said last week.

Australia is forecast to produce 34.77 million metric tons of winter crops such as wheat, barley and canola, in the 2009-10 fiscal year, the biggest crop since 2005-06, according to the Australian Bureau of Agricultural and Resource Economics.

Should ocean conditions remain at current levels through the southern winter and spring, "2009 will be considered an El Nino year," Australia's Bureau of Meteorology said June 22.