Puerto Rico: Flash flood warning in effect for several municipalities until at least 21:00 Sept. 20

The US National Weather Service (NWS) has issued a flash flood warning for several municipalities of Puerto Rico on Sept. 20. The warning is in effect until at least 21:00 and covers Bayamon, Catano, Guaynabo, San Juan, and Toa Baja municipalities. Officials could amend the warning for the impacted areas and/or extend it to the surrounding regions on short notice over the coming hours.

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 the soil has become saturated by heavy rainfall.

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. Transport, electricity, and telecommunications disruptions are also possible in areas impacted by flooding.