The shocking sinkhole is already 20 metres wide and 30 metres deep. It opened up on May 30 during the Pacific hurricane season's first named tropical storm, Agatha.
Guatemala City has been getting torrential downpours amounting to the area's heaviest rainfall in decades.
The sinkhole is now covered with plastic tarps to keep the rains from weakening its walls. A disaster agency has fenced of the area and is using radar to assess the earth's stability.
Guatemala, Honduras and El Salvador are facing a multimillion dollar cleanup from Agatha, which caused deadly landslides and flooding.
The storm made landfall near the Guatemala-Mexico border with winds of 75 km/h. At least 184 people have lost their lives.
Most of the deaths have been in Guatemala, but there have also been fatalities in El Salvador and Honduras. In some cities, bridges have been washed away and massive sinkholes have opened up. Sinkholes are often formed when groundwater flows through the rocks and eats away at them. This leaves underground holes and caverns.
One resident who lived close to the Guatemala City sinkhole says the neighbourhood was very old.
“There are very old neighbourhoods with infrastructure such as this one, which is very old indeed. Besides, there are professionals who specialize in the matter and there is special equipment which allows to detect the state that infrastructure is in.” Officials say no one could have prevented this disaster.
Tens of thousands of people have been forced to leave their homes. Central America is vulnerable to heavy rains due to its mountainous terrain, while poor communications in rural areas complicate rescue efforts.
Last November's Hurricane Ida caused flooding and mudslides that killed at least 150 people as it moved through the region.
When Agatha hit, Guatemala was already under a 15-day state of calamity due to a recent volcanic eruption. The volcano also shut down the capital's international airport.
The 2010 Atlantic hurricane season is now officially under way. Forecasters are predicting an “active” to “extremely active” season.