The tides seeped into households as well when water level started to increase on Monday afternoon.
Announcements through loudspeakers are on calling people to shift to shelter homes.
Cyclone Mora has moved further north to Bangladesh coast, prompting the Met Office to advise danger signal No 10 for ports in Chittagong and Cox’s Bazar.
Coastal districts of Chittagong, Cox’s Bazar, Noakhali, Lakshmipur, Feni, Chandpur and their offshore islands will be covered by the signal.
Medium rainfall was reported from Cox’s Bazar on early Monday. Drizzling continued throughout the day, said Cox’s Bazar Met office representative, AKM Nazmul Hoque.
High tide waters entered residential areas in the afternoon, said Cox’s Bazar municipality Ward 1 Councillor Akter Kamal.
“People at Samity Para, Najirartek, Fodnardeil and Kutubdia are in woes.”
Locals said high tides have flooded lowlands in Kutubdia, Moheshkhali and Teknaf as well.
Volunteers from Bangladesh Red Crescent Society are alerting residents through loudspeakers to take shelter at their nearest cyclone shelter homes.
Cox’s Bazar Fishing Boat Owners Association Organising Secretary Mostak Ahmed said some fishing trawlers had moved back to the shore while some were still operating at the Bay.
Coastguards were trying to bring them back, he added.