Colombia's meteorological authorities have maintained red alerts for the main rivers and river basins in the country's Andean region, the UN Office for the Coordination of Humanitarian Affairs (OCHA) reported.
More than 2 million Colombians were affected by last year's floods, and in some places flood waters are yet to recede, according to OCHA.
The governors of some affected departments are reporting that this year's flooding is worse than last year's inundations, and the cumulative toll has risen to 410 people dead and 482 others missing.
"The emergency in some areas of the country is not yet over, and we are really concerned about the impact of the new rainy season on already affected communities," said Stephanie Bunker, a spokesperson for OCHA.
A food security assessment conducted by the UN World Food Programme (WFP) earlier this year found that the food security and nutrition situation in flood-affected areas have deteriorated sharply, with many households along the Caribbean and Pacific coasts - among the hardest-hit areas - reducing their number of daily meals to two or even one.