Australia sees La Nina weather staying for months

The early morning sky illuminates dead trees and cracked earth on a farm near Kerang, about 360km (224 miles) north of Melbourne, in this August 24, 2007 file photo.

SYDNEY (Reuters) - A mature La Nina weather pattern in the Pacific continued to influence the climate of eastern Australia and was forecast to remain until at least the end of the southern autumn, the Australian Bureau of Meteorology said on Wednesday.

La Nina weather patterns, the opposite of El Ninos, are associated with wet weather in eastern Australia and Southeast Asia.

After being hit by its worst drought in 100 years, eastern Australia has been abnormally wet this year.

Cooler than average sea surface temperatures continued to extend across the central equatorial Pacific, the bureau said in an update of its La Nina report.

Trade winds were also stronger than average across the central to western equatorial Pacific, while cloudiness in the central Pacific has been much below average in recent months.

The Southern Oscillation Index was also strongly positive, indicating wet weather, the bureau said.

"It is clear that the atmosphere and ocean are firmly reinforcing each other, sustaining the La Nina event," it said.

The Southern Oscillation Index is a measure of atmospheric pressure differences between Darwin in northern Australia and Tahiti in the central Pacific.

El Nino weather conditions are typically associated with droughts in eastern Australia and Southeast Asia, while La Nina conditions are associated with wet weather.

Both weather effects are produced by abnormal sea temperatures in the Pacific.

(Reporting by Michael Byrnes.)