Updated at 10:50 p.m. ET

Robert Oerlemans/AP

Boats are pulled ashore as smoke and bushfires rage behind Australia's Lake Conjola on Thursday. Thousands of tourists fled the country's fire-ravaged eastern coast this week ahead of worsening conditions.

Prime Minister Scott Morrison is calling up 3,000 reservists for operations related to the massive bushfires in eastern Australia that have forced mass evacuations and killed at least 11 people since Monday.

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A firefighter sprays foam retardant on a back burn ahead of a fire front in the New South Wales town of Jerrawangala on New Year's Day.

Record heat has contributed to the ferocity of blazes. Flames now threaten the outskirts of the country's largest city, Sydney.

POIS Helen Frank/Australian Defence Force

Evacuees walk to the beach at Mallacoota in Victoria to board vessels and be ferried out.

Authorities are warning of worsening conditions over the weekend. The rural fire service deputy commissioner for New South Wales, Rob Rogers, has warned of the "frighteningly quick" advance of the blazes.

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Crews monitor fires and begin back burns between the towns of Orbost and Lakes Entrance in East Gippsland, east of Melbourne, on Thursday.

"With the fuel loads that we've got and the drought conditions and the current weather conditions that we have, frankly, we can't put these large fires out," Mick Holton, president of the Volunteer Fire Fighters Association, told NPR's Morning Edition.

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A view of fire damage on Friday in Sarsfield, east of Melbourne. Thousands of people have been stranded in the remote coastal town following fires across East Gippsland.

Holton says firefighters are at the mercy of changing weather conditions.

POIS Helen Frank/Australian Defence Force

HMAS Choules, aiding in the evacuations, is seen off the coast of Mallacoota, Victoria.

"We're paying the price for probably lack of fuel management," he added.

LSIS Shane Cameron/Australian Defence Force

Evacuees from Mallacoota are transported by landing craft to MV Sycamore.

Forecasters from Australia's Bureau of Meteorology expect the weather on Saturday to intensify the fire dangers in New South Wales and Victoria.

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Bushfires are seen between the towns of Orbost and Lakes Entrance in East Gippsland on Thursday. HMAS Choules evacuated thousands of people stranded in the remote coastal town of Mallacoota.

In a Saturday morning local time update, one forecaster said, "The changes arriving later in the day today, in comparison to New Year's Eve, [are] giving more time for those strong" winds to affect the fire regions.

Peter Parks/AFP via Getty Images

A helicopter drops water on a bushfire outside of Batemans Bay in New South Wales on Thursday.

Temperatures are expected to reach into the low- to mid-40 degrees Celsius in some parts of the two states. That's between 104 and 114 degrees Fahrenheit.

DELWP Gippsland/AP

Smoke rises from a massive bushfire in this image released Thursday by the Department of Environment, Land, Water and Planning in Gippsland, Victoria.

The warnings come after two people were killed Saturday in a blaze that devastated a large swath of Kangaroo Island, police told the Australian Broadcasting Corporation.

ABC reports "up to 150,000 hectares — about a quarter of the island — has been burnt and authorities are warning of significant property losses."

"Victoria Police Chief Commissioner Graham Ashton said the number of people missing now stood at 21, seven fewer than the number unaccounted for 24 hours earlier," ABC reported.

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