Dominican Republic, Haiti: Adverse weather forecast across the Dominican Republic and Haiti through at least May 27

Event

Heavy rainfall, thunderstorms, and strong winds are forecast across parts of Haiti and the Dominican Republic through at least May 27. The adverse weather could trigger flooding, landslides, and associated disruptions in areas of the affected countries.

The Dominican Republic's National Office of Meteorology (ONAMET) has warned that a trough that has brought heavy rainfall, thunderstorms, and strong winds to parts of the country in recent days will continue to cause unstable conditions in many regions. Moderate downpours with isolated heavier showers, thunderstorms, and strong gusts of winds are likely in Eastern Plains, Eastern Sierra, Central Cordillera, Cibao Valley, and border regions May 26. Showers will become more intense throughout May 27 and again could be accompanied by thunderstorms and strong wind gusts in the northeast, southeast, Cibao Valley, and Central Mountain Range. Due to the possibility of flooding and landslides, weather alerts (the middle level on a three-tier scale) have been issued for Duarte, Maria Trinidad Sanchez, San Juan, San Pedro de Macoris, Santiago Rodriguez, and Santo Domingo provinces. Weather notices are in place for Hato Mayor, La Vega, Monsenor Nouel, Monte Plata, Sanchez Ramirez, San Jose de Ocoa, and Santiago provinces.

The Hydro-Meteorological Unit of Haiti (UHM) has warned that the influence of a tropical wave is expected to bring stormy conditions across much of the country through at least May 27. The departments expected to be most affected include Artibonite, Center, Grand'Anse, Nippes, Ouest, and Sud-Est. Stormy showers are expected to be largely concentrated in the afternoons and evenings.

Authorities in the Dominican Republic reported two fatalities after six people were swept away by the overflowing Camu River in La Vega Province following heavy rainfall May 23. Further downpours in the coming days are likely to exacerbate the situation in areas where the ground is already saturated, and river levels are high following previous heavy rainfall.

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 regional airports. If strong winds trigger hazardous sea conditions, authorities may temporarily suspend port operations or close beach fronts. 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

Hydro-Meteorological Unit of Haiti (UHM)
Dominican Republic National Office of Meteorology (ONAMET)