The October 2008 Central America floods were caused by a series of low-pressure areas including Tropical Depression Sixteen, a short-lived tropical cyclone in the 2008 Atlantic hurricane season that made landfall in Honduras. Heavy rainfall began in early October 2008 while a tropical wave passed through the region. On October 14, Tropical Depression Sixteen formed just off the northeast coast of Honduras, and at the same time a low-pressure system was on the Pacific coast. Both systems increased rainfall across the region, although the depression dropped heavy rainfall close to its center when it moved ashore on October 15. Although Tropical Depression Sixteen quickly dissipated over land, its remnants persisted for several days. Another low-pressure area interacted with a cold front on October 21, adding to the rainfall in the region.

Heavy rainfall extended from Costa Rica to southeastern Mexico, causing what was considered the worst natural disaster in the region since Hurricane Mitch in 1998. In the former country, rainfall totaled over several weeks, making the week ending October 17 the wettest in San José since 1944. Floods in Costa Rica damaged 32 bridges and roads in 174 locations, while 1,396 homes were damaged, killing seven people. In Nicaragua to the north, weeks of heavy rainfall killed 16 people and damaged or destroyed 1,333 houses. In Honduras where the tropical depression made landfall, rainfall reached in some areas, although the highest official total there related to the depression was on the offshore Roatán over six days. About 40% of municipalities in the country experienced flooding, forcing over 50,000 people to leave their homes. The floods damaged about 50% of roads in Honduras, and over 10,000 houses were damaged or destroyed. Damage totaled about 3 billion lempiras (HNL, $225 million USD), and there were 60 deaths.

In northern Guatemala, the floods damaged about of crop fields, accounting for Q128.9 million (2008 GTQ, US$16.8 million) in crop damage. There were 17 deaths and about 4,000 damaged houses in Guatemala. In neighboring El Salvador, the rains contributed to October 2008 being the third-wettest month across the country, after Hurricane Stan in 2005 and Hurricane Mitch in 1998. One person died, and hundreds were forced to evacuate their houses. In Belize, the rains flooded about 1,000 homes, forcing the evacuation of one entire town for health reasons. The rains caused additional flooding following Tropical Storm Arthur striking the country in May, damaging a bridge that was rebuilt after Arthur. Nationwide, the floods caused BZ$54.1 million (BZD, US$27.1 million) in damage and two deaths.

Meteorological history

Widespread rainfall occurred throughout Central America in early October 2008 due to the passage of a tropical wave through the region. Later, another tropical wave approached the region, which was believed to have left the west coast of Africa on September 17. The wave developed a low-pressure area on October 10 in the southwestern Caribbean, with sporadic convection. On October 13, the system consisted of a large area of convection drifting northward offshore eastern Central America, and Dvorak classifications began, indicating gradual organization. At that time, there was another low-pressure area on the Pacific coast, and both systems were producing rainfall across Central America.

At 1200 UTC on October 14, the National Hurricane Center (NHC) indicated that Tropical Depression Sixteen developed about northeast of Cabo Gracias a Dios, a point where the border of Nicaragua and Honduras meet the Caribbean. In the hours after the depression's formation, the convection decreased, and hurricane hunters indicated that the small low-level circulation was rotating around a broader circulation. Shortly after 1200 UTC on October 15, the weak tropical depression made landfall just west of Punta Patuca in northern Honduras, with a broad and ill-defined circulation. Continuing west-southwestward over land, the circulation dissipated on October 16 over the mountains of central Honduras, although the depression's remnants continued to produce rainfall across the region for several days. On October 21, a cold front was moving through the Yucatán Peninsula, interacting with a newly formed low in the Gulf of Honduras to produce additional rainfall.

Preparations Around the time when the NHC began issuing advisories on the depression, officials issued a tropical storm warning for northern Honduras that eventually covered the country's entire coastline. A tropical storm warning was also issued for the coast of Belize. When the NHC began issuing advisories on the depression, the agency anticipated the depression would intensify into a strong tropical storm, based on low wind shear and warm sea surface temperatures; however, the agency noted uncertainty in the track. A ridge to the north was expected to steer the nascent depression westward, and two tropical cyclone forecast models predicted the storm would continue west-northwestward to strike Belize. Other models forecast a more immediate landfall, which would limit intensification. While the storm was active, officials in Honduras issued a yellow alert for seven departments where heavy rainfall had occurred. A nationwide yellow alert was also issued for El Salvador, meaning there was potential for flooding and landslides, although alerts were dropped on October 21 when the threat of rainfall diminished.

Impact Although a weak tropical cyclone, the depression and its remnants dropped heavy rainfall across Central America for several days, spreading into Nicaragua, Honduras, Guatemala, and Belize. In Honduras where it made landfall, rainfall peaked at on the offshore Roatán over six days. A member from Mercy Corps estimated the rainfall in October to have totaled around in some areas. On the mainland, rainfall reached at El Empalme. In El Salvador, the depression dropped heavy rainfall, mainly in the southern coastal portion, with a 24-hour peak of in Puerto Parada en La Unión. Over a period of eight days, rainfall in Belize reached at Baldy Beacon. Rainfall extended as far north as southeastern Mexico. Throughout the region, the flooding destroyed about 10,000 homes and left about 250,000 people homeless. News agencies considered the flooding the worst in the region since Hurricane Mitch in 1998.

According to Costa Rica's National Meteorology Institute, the week ending on October 17 was the wettest in San José since 1944. Over a period of several weeks, rainfall reached about . The influence between the precursor to the depression and a low-pressure area in the eastern Pacific caused flooding in Costa Rica that killed seven people. In Guanacaste Province, a landslide covered three cars, and in Monteverde, another landslide knocked over a power line that killed two people. In Parrita, an ambulance carrying four people was struck by a fallen tree, while in Puntarenas, another vehicle was struck by a tree, killing one of its occupants. Transport was disrupted in widespread areas in the north and south of the country due to landslides blocking roads. Across the country, the floods compromised roads in 174 locations and damaged 32 bridges. Flooding isolated about 6,900 people in 75 communities, and about 77,000 people were forced to leave their homes. Power outages affected 89 communities, and 424 water wells along the Pacific coast were polluted. Nationwide, the floods damaged 1,396 houses and 39 schools.

In early October, heavy rainfall began affecting Nicaragua, causing mudslides and flooding. The tropical depression added to weeks of heavy rainfall that killed 16 people, many caused by people attempting to cross swollen rivers. Toward the end of October 2008, Lake Managua overflowed, causing flooding in the capital city of Managua. Across the country, 2,273 people evacuated to storm shelters after the floods damaged or destroyed 1,333 houses. Transportation was disrupted when the floods wrecked four bridges and of highways. Classes were canceled in León and Chinandega departments. The crops in the latter department were almost entirely destroyed.

Following months of drought conditions, the heavy rainfall in Honduras caused flooding, initially in the southern and central portions, although the entire country experienced rainfall, with 40% of municipalities experiencing flooding. The rains caused widespread landslides, particularly in the western and central portions. In the capital city Tegucigalpa, the rainfall in October was estimated to have been twice the average annual total. In two locations, the Pan-American Highway was disrupted by either landslide or flooding, and widespread areas were isolated nationwide by flooded roads. According to Reuters, about 50% of the roads in Honduras were damaged during the floods, with 227 roads and 106 bridges damaged. A landslide near Corquín blocked a river and created a natural dam, forcing hundreds of nearby residents to leave. In Colón Department, the Tocoa River overflowed, while flooding in Atlántida damaged crop lands. A total of of crops were damaged, mostly in Comayagua Department. 14 water systems were damaged, and 150,000 people lost power in Olancho Department. Landslides in Tegucigalpa killed six and displaced about 500 people. In El Progreso, 375 inmates from a jail had to be evacuated to another facility. A total of 50,676 people were forced to evacuate in the country, most of whom stayed in shelters. 2,474 homes were destroyed in Honduras, with another 8,688 damaged or flooded. In addition, at least nine schools were damaged or destroyed. Nationwide, the floods killed 60 people, and damage was estimated at about 3 billion lempiras (HNL, US$225 million). The low death toll compared to Hurricane Mitch was largely due to the widespread evacuations.

Floods in Guatemala overflowed rivers and caused landslides in Izabal and Petén departments, blocking many roads. The rising rivers damaged about 175 houses, forcing hundreds of people to leave their homes. About of crop fields were damaged or destroyed, including corn, rice, and beans, and crop damage nationwide was estimated at Q128.9 million (2008 GTQ, US$16.8 million). About 2.5% of the national corn crop and 3.7% of the rice crop were wrecked during the floods. Nationwide, about 4,000 houses and 82 roads were damaged or destroyed, and 17 people died in the country from the floods. In neighboring El Salvador, floods affected the houses of about 600 families. High levels forced officials to release water from several dams, causing urban flooding. Along the coastline, the floods damaged maize and bean crops. The average rainfall across El Salvador for the month of October was . This was the third-highest for October since such record keeping began in 1971, after 2005 when Hurricane Stan struck and 1998 when Hurricane Mitch crossed the area. The tropical depression killed one person in the country.