Once the building is down, rescue efforts will resume, Miami-Dade County Mayor Daniella Levine Cava said, as beachside communities planned more subdued events for the Fourth of July.
Preparations for demolition work have gotten underway ahead of the possible arrival of Tropical Storm Elsa at the partially collapsed Miami-area condo where 24 are confirmed dead.
Search and rescue efforts for 121 people missing have been suspended.
"Our top priority is that the building come down as soon as possible no matter what time that occurs," Miami-Dade County Mayor Daniella Levine Cava told reporters on Sunday. "We do not know a specific time the demolition will occur."
Once the building is down, rescue efforts will resume, she said, noting it was 11 days since the collapse.
As of Sunday morning, Tropical Storm Elsa was off the coast of Jamaica with winds of 95 km per hour (60 miles per hour). On Monday the storm was forecast to move across Cuba and hit western Florida on Tuesday or Wednesday.
In the wreckage of the Champlain Towers South complex in Surfside, workers were drilling into columns where small explosive charges will be placed to bring the remains of the building down in a small area, officials said.
Residents in nearby buildings do not need to evacuate but should stay indoors due to dust, the mayor said.
Instead of the usual fireworks and flag-waving parties, beachside communities in the area have planned more subdued events for the Fourth of July. Miami Beach canceled its Independence Day celebrations.
Investigators have not determined what caused the 40-year-old complex to collapse on June 24. A 2018 engineering report found structural deficiencies that are now the focus of inquiries that include a grand jury examination.
Meanwhile, all residents of another building, Crestview Towers in North Miami Beach, were told on Friday to leave immediately after engineers found serious concrete and electrical problems, officials said.
The move was considered urgent due to the approach of Elsa, North Miami Beach city manager Arthur Sorey said, adding that the building's owners had not yet begun a mandatory safety recertification process required 40 years after it was built.
"It's definitely not an easy decision," Sorey said. "It's just the right thing to do during these times. It's uncertain what's going to happen with the storm."