The port city recorded over 40 mm of rainfall in three hours on Saturday, flooding several parts of the city.
The residents of the city experienced sporadic rains from 8 am to 11 am.
The Patenga weather office has recorded 48 mm of rainfall between 6 am and 12 pm.
It recorded 43 mm of rainfall between 9 am and 12 pm.
"It has been raining with gusty winds due to a storm, said Biswajit Chowdhury, forecast official at the Patenga met office.
Different areas and neighbourhoods, including 2 No. Gate, Chawkbazar, Kapasgola, Kalamia Bazar, Badurtola, Jongi Shah Mosque gate, Boro Mia Jame Masjid, KB Aman Ali Road and Phultala were faced with ankle to knee-deep water.
"Chawkbazar, Boro Mia Jamme Masjid, Phultala and KB Aman Ali Road were flooded after the rain. People had to wade through dirty water to get to work," said Rumon Bhattacharya, a resident of the port city's Chawkbazar area.
"The students suffered most of all. They went to school fully drenched."
Md Raihan, who was heading to Agrabad from 2 No. Gate area, said, "The road has previously flooded when there has been less rain than this. Waterlogging is a daily reality here during the rainy season. It's really scary to commute on this potholed road."
The construction of four separate projects worth Tk 100 billion is underway to curb waterlogging in the city. The Chattogram Development Authority is implementing the largest project, which costs Tk 65 billion.
The 34 Engineer Construction Brigade of the Bangladesh Army is carrying out the construction of the CDA project. Several canals in the city were blocked by dams due to the construction of the project.
Councillor Mubarak Ali, chairman of Chattogram City Corporation's standing committee on the matter, blamed the blocking of the canals for waterlogging.
"We have submitted a list asking the CDA authorities to remove dams on the canals ahead of the rainy season. They said they will unblock them soon."
"Some dams have already been removed but the remaining ones are causing waterlogging," he added.