Emergency services were put on standby Saturday in Majuro, as rising king tides threatened to flood the capital of the low-lying Marshall Islands.
The national weather service warned "major inundation" was possible from Saturday evening through to Tuesday at peak tide periods in the Pacific island nation, highlighting its vulnerability to rising sea levels.
"We're on stand-by through Tuesday," Public Works Minister Tony Muller said Saturday as the 30,000 population of Majuro Atoll braced for the expected floods.
Heavy equipment, including bulldozers, was being positioned at critical locations around Majuro so emergency crews can respond quickly in the event of flooding, he said.
Majuro is barely a metre above sea level and the single road along the 30-mile (50-kilometre) length of the coral atoll is often blocked during serious flooding by coral, rocks, sand and garbage tossed up by waves.
The National Disaster Management Office has been placed on high alert and used its mass text messaging system for the first time Friday to issue a high tide advisory.
The US National Weather Service in nearby Guam issued an advisory Saturday morning warning "major inundation of one to two feet is possible, especially during high tides inside the lagoon".
King tides, which are extremely high tides, are a natural phenomenon early in the year in the Marshall Islands caused by the strong gravitational pull from a new or full moon when the moon is at its closest to the earth.