SURFSIDE, Fla. (AP) — Officials overseeing the search at the site of the Florida condominium collapse seemed increasingly somber Tuesday about the prospects for finding anyone alive, saying they have detected no new signs of life in the rubble as the death toll climbed to 36.

Miami-Dade Mayor Daniella Levine Cava said Tuesday evening that 29 of the 36 victims have been identified.

With noise from power saws and backhoes in the background, crews in yellow helmets and blue jumpsuits searched the debris for a 13th day while the weather complicated their efforts. Wind and rain from outer bands of Tropical Storm Elsa lashed the Miami area.

Search-and-rescue workers continued to look for open spaces where people might be found alive nearly two weeks after the disaster struck at the Champlain Towers South building in Surfside.

“We’re actively searching as aggressively as we can,” Miami-Dade County Fire Chief Alan Cominsky said at a news conference. But he added: “Unfortunately, we are not seeing anything positive. The key things — void spaces, living spaces — we’re not seeing anything like that.”

While officials still call the efforts a search-and-rescue operation, Levine Cava said families of those still missing are preparing for news of “tragic loss.”

“I think everybody will be ready when it’s time to move to the next phase,” said Levine Cava, who stressed that crews would use the same care as they go through the rubble even after their focus shifts from searching for survivors to recovering the dead.

Officials say 109 people remain unaccounted for, though only 70 of those are confirmed to have been inside the building when it collapsed, Levine Cava said.

“Really, you will not see a difference,” she said. “We will carefully search for bodies and belongings, and to catalog and respectfully deal with any remains that we find.”

No one has been rescued alive since the first hours after the collapse, which struck early on June 24, when many of the building’s residents were asleep.

Severe weather from Elsa threatened to hinder search efforts. Lightning forced rescuers to pause their work for two hours early Tuesday, Miami-Dade Assistant Fire Chief Raide Jadallah said. And stiff winds of 20 mph (32 kph), with stronger gusts, hampered efforts to move heavy debris with cranes, officials said.

However, the storm’s heaviest winds and rain were expected to bypass Surfside and neighboring Miami as Elsa strengthened before making landfall somewhere between Tampa Bay and Florida’s Big Bend on a path across northern Florida.

“Active search and rescue continued throughout the night, and these teams continue through extremely adverse and challenging conditions,” Levine Cava said. “Through the rain and through the wind, they have continued searching.”

Crews have removed 124 tons of debris from the site, Cominsky said.

Workers have been freed to search a broader area since the unstable remaining portion of the condo building was demolished Sunday amid fears that the structure could fall. Officials said the demolition gave rescuers access to spaces that were previously closed off, including bedrooms where people were believed to be sleeping at the time of the disaster.