The Australian Maritime Safety Authority, which is coordinating the southern search operation Malaysia's behalf, said the focus Wednesday will be on an 80,000 square kilometer (30,900 square miles) swathe of ocean. Ships and aircraft are looking for possible debris that has drifted from the suspected crash zone. The area is about 2,000 kilometers (1,240 miles) southwest of Perth.
Various pieces of floating objects have been spotted by planes and satellite, but none have been retrieved or identified.
Australia's Bureau of Meteorology warned that weather was expected to deteriorate again Thursday with a cold front passing through the search area that bring rain thunderstorms, low clouds and strong winds.
Malaysia announced Monday that a complex analysis of satellite data by foreign experts had concluded that flight had ended in a remote corner of the Indian Ocean, far from any landing strip.
The conclusions were based on an analysis of the brief signals the plane sent every hour to a satellite belonging to Inmarsat, a British company, even after other communication systems on the jetliner shut down for unknown reasons.
The airline's chairman, Mohammed Nor Mohammed Yusof, warned it may take a long time for further answers to become clear.
"The investigation still underway may yet prove to be even longer and more complex than it has been since March 8th," he said.
Pitman reported from Kuala Lumpur. AP writers Eileen Ng in Kuala Lumpur, Christopher Bodeen and Didi Tang in Beijing, Danica Kirka in London and Kristen Gelineau in Sydney contributed to this report.
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