Central America: Adverse weather forecast across parts of Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama through at least May 23

Event

A low pressure system known by meteorologists as the Central American Gyre is forecast to bring heavy rainfall across parts of Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama through at least May 23. The US National Weather Service's National Hurricane Center Tropical Analysis and Forecast Branch has warned of a risk of extremely intense downpours and potential flooding across much of the region. The area most at risk of heavy rainfall includes parts of southern Guatemala, much of El Salvador, southern and eastern Honduras, northern and western Nicaragua, western Costa Rica, and southeastern Panama. Rainfall totals of around 15 cm (6 inches) are expected across the affected areas, especially over windward mountainous areas. Flash flooding and mudslides are possible where significant downpours occur. Light-to-moderate downpours are expected in surrounding areas.

As of May 18, meteorological agencies across the affected region have forecast heavy rainfall and thunderstorms in the coming days, and some have issued weather warnings:

Guatemala's National Institute of Seismology, Volcanology, Meteorology, and Hydrology (INSUVIMEH) has forecast thunderstorms and rainfall across much of the country May 17-19, with the heaviest downpours likely in southern regions. The institute has warned of possible flooding and landslides in southern regions of the country May 17-19.

El Salvador's Directorate-General for the Observatory of Threats and Natural Resources has forecast heavy rainfall and thunderstorms across much of the country May 18-19.

The Permanent Contingency Commission (COPECO) of Honduras has forecast weak-to-moderate rainfall over southern and southwestern regions May 18, with light rainfall across the rest of the country.

The Nicaraguan Institute of Territorial Studies has forecast showers and thunderstorms of varying intensity across the country May 18.

Costa Rica's National Meteorological Institute issued a weather warning for heavy rainfall along the Pacific Coast May 17 and warned that showers will likely intensify May 19-20.

Panama's Hydrometeorological Service has issued an amber warning due to the influence of a tropical wave and low pressure system, which will bring heavy rainfall and a risk of flooding and landslides across most of the country May 17-20.

Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Hazardous Conditions

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rainfall has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Transport

Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

Severe weather could also trigger flight delays and cancellations at airports across the affected region. If strong winds trigger hazardous sea conditions, authorities may temporarily suspend port operations or close beach fronts along the Pacific and Atlantic coasts. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.

Advice

Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

Guatemala National Institute of Seismology, Volcanology, Meteorology, and Hydrology (INSUVIMEH)
San Salvador Directorate General for the Observatory of Threats and Natural Resources
Honduras Permanent Contingency Commission (COPECO)
Nicaragua Institute of Territorial Studies
Costa Rica National Meteorological Institute
Panama Hydrometeorological Service