South African media reported that Eline was moving closer to Mozambique after sweeping across the Indian ocean island of Madagascar over the weekend, where it left five people dead.
Eline also made thousands homeless as it crossed Madagascar.
The cyclone, which on Sunday was reported to be some 250 km (150 miles) from Mozambique, was expected to hit the mainland in the southern coastal province of Inhambane as well as Gaza province.
Weather experts said it would also strike Sofala in central Mozambique.
Eline, moving at 24 km (15 miles) per hour could bring further torrential rains and winds of up to 120 kph (70 mph), the South African Press Association (SAPA) reported.
The rain will compound the misery of more than 200,000 Mozambicans who have lost homes, washed away by flooding after nearly two weeks of rain.
The Mozambican government has given no official death toll for the floods but local newspapers say at least 48 have died.
The southern water authority has warned that another flood peak would hit the region as the Limpopo River, which has already burst its banks, brings more flood water from neighbouring South Africa.
Mozambican President Joaquim Chissano met members of his cabinet on Sunday and the government was expected to make a second appeal for more international aid.
Chissano toured flood-stricken areas to see the damage for himself.
SOUTH AFRICA HELPS MOZAMBIQUE
South Africa, the region's economic giant, is helping impoverished Mozambique battle its disaster. Pretoria has provided military helicopters to create a vital communications link after many roads were made impassable by high water.
The South African Weather Bureau said the tropical storm would bring more rain and strong winds to South Africa's Northern Province and Mpumalanga, the regions worst hit by flooding earlier this month.
More than 45 South Africans were killed in the floods, the worst for 50 years in the north of the country.
United Nations officials estimate that 220,000 Mozambicans have already been forced out of their homes by floods this month in the worst-hit provinces, Maputo and Gaza.
The rains have also dislodged landmines, a legacy of the 16-year civil war which ended in 1992, increasing the danger they pose.
- Reuters - Thomson Reuters Foundation
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