Caribbean: Adverse weather forecast across the Dominican Republic, Haiti, Puerto Rico, and the US Virgin Islands through at least Feb. 8

Adverse weather conditions are forecast across much of the Dominican Republic, Haiti, Puerto Rico, and the US Virgin Islands through at least Feb. 8. A weather front moving over the region is expected to bring heavy rainfall and isolated thunderstorms over the coming days. Strong winds, lightning, and possible hail may accompany storms. Heavy downpours may trigger flooding in low-lying areas and landslides on unstable slopes.

As of early Feb. 6, the Dominican Republic's National Office of Meteorology (ONAMET) has warned of showers and storms spreading across much of the country Feb. 6, before moving away Feb. 7. The heaviest rainfall is likely in western regions. Due to the possibility of flooding and landslides, weather alerts (the lowest level on a two-tier scale) have been issued for Barahona, Independencia, Monte Cristi, Pedernales, and Puerto Plata provinces.

The Haiti Hydrometeorological Unit (UHM) has forecast moderate to heavy rainfall across much of the country Feb. 6-7. The heaviest rainfall is likely in parts of Artibonite, Centre, Nord-Ouest, Ouest, Sud-Est, and Sud departments.

The US National Weather Service (NWS) is maintaining a flood watch across Puerto Rico and the US Virgin Islands through late Feb. 7. Rainfall accumulation of 7.5-15 cm (3-6 inches) are expected in the interior, eastern, and southern parts of Puerto Rico and 5-10 cm (2-4 inches) in the US Virgin Islands; localized heavier amounts of up to 20 cm (8 inches) are possible in places.

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

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.

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.