Puerto Rico: Flooding and power outages reported in Puerto Rico following passage of Tropical Storm Isaias July 30 /update 1

Event

Flooding and power outages have been reported across Puerto Rico on Thursday, July 30, following the passage of Tropical Storm Isaias to the southwest of the island. Small landslides and widespread flooding have occurred, and some 300,000 people are without power across the island. The worst affected areas are in the southwest of the island, where a number of neighborhoods damaged by an earthquake in January have been flooded. Puerto Rican authorities have activated the National Guard and prepared over 300 shelters across the territory for emergency use. No injuries or fatalities linked to storm-related incidents have yet been reported.

Previously a Potential Tropical Cyclone, Isaias strengthened to a Tropical Storm on Wednesday, July 29. As of 11:00 AST, Tropical Storm Isaias is centered 35km (21 miles) south of La Romana province (Dominican Republic) and sustaining winds of up to 97kmh (60mph). Isaias is forecast to move northwest over Hispaniola during the evening of Thursday and will bring heavy rains with the potential for flash flooding and mudslides in the Dominican Republic and northern Haiti. The National Hurricane Centre (NHC) has stated that due to Isaias' forecast passage over Hispaniola, the details of its tack and its predicted intensity remain unclear.

Tropical storm conditions are forecast to persist into Thursday afternoon in Puerto Rico. Associated disruptions to transport and businesses are also expected.

Context

The Atlantic hurricane season runs from late May through to the end of November, with activity typically peaking in late August and early September. Numerous tropical storms form in the Atlantic Ocean during this period, with most affecting the Caribbean, the Gulf of Mexico, and the east coast of the United States. Although communities in the region are generally well prepared for adverse weather conditions during the hurricane season, severe storms bring a significant risk of flooding and infrastructural damage.

Given Puerto Rico's location within the Caribbean hurricane belt, there is generally some level of tropical storm activity every year from June through November. However, this does not necessarily imply full hurricanes, but rather a range of activity from disorganised tropical bands to high-intensity hurricanes. The territory's relatively high level of development and the ability to leverage US federal assistance generally means that it is able to mount recovery and reconstruction efforts better than other island nations in the region.

Advice

Those in the affected areas are advised to monitor local weather reports, anticipate transportation disruptions, avoid areas directly affected by flooding, confirm road conditions before setting out, and adhere to instructions issued by local authorities, including evacuation orders. Avoid walking or driving through floodwaters.