Tropical Depression Hanna on Monday lashed northeastern Nicaragua and eastern Honduras, unleashing heavy rains that US forecasters warned could cause deadly flash-flooding.

Though slightly weaker and downgraded from tropical storm status, Hanna still could drench much of Honduras and northern Nicaragua with up to 15 inches (38 centimeters) of rain, according to the Miami-based National Hurricane Center.

"These rainfall amounts will produce life-threatening flash floods and mudslides," the NHC cautioned at 0001 GMT Tuesday.

Hanna, with top winds of 55 kilometers (35 miles) per hour, was forecast to move quickly inland and bring downpours to the region.

While heavy rains might sound like good news for parts of Honduras that have been experiencing drought, the dry conditions actually make the terrain in mountainous Central America more prone to mudslides.

And elsewhere in Honduras and in Nicaragua, the rainy season has saturated the soil, causing rivers and streams to overflow easily and triggering landslides on the slopes of volcanoes and mountainous areas across the countries.