Brazil: Adverse weather forecast across southern regions through at least April 16

Severe weather is forecast across parts of southern Brazil through at least April 16. A low-pressure system is forecast to move across the region, bringing heavy rainfall and strong winds to affected areas. Rainfall totals of 3-10 cm (1.2-3.9 inches) are expected across the region, with isolated heavier amounts. The heaviest downpours are likely in coastal parts of Santa Catarina State. Sustained heavy rainfall may trigger flooding in low-lying areas and landslides on unstable slopes. Strong winds may cause property damage and power outages.

As of early April 15, Brazil's National Institute of Meteorology (INMET) has issued red heavy rainfall warnings (the highest level on a three-tier scale) for coastal areas of Santa Catarina State and orange rainfall warnings across the rest of the affected area. Orange coastal wind warnings are in place for coastal parts of the affected area. Officials could update and possibly extend the coverage of the relevant weather alerts over the coming days.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. In developed areas with easily overwhelmed stormwater drainage systems, additional urban flooding is also possible. Sites downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides remain possible in hilly or mountainous areas, especially where heavy rainfall has saturated the soil. Power outages and disruptions to telecommunications services are likely where significant flooding, landslides, or strong winds impact utility networks.

Floodwaters and debris flows could render some bridges, rail networks, or roadways impassable, impacting overland travel in 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 intermittent flight delays and cancellations at airports in the affected regions, though these are unlikely to be severe or prolonged. Authorities may temporarily suspend port operations or close beach fronts along the Atlantic coast if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are possible in areas with heavy rainfall and track inundation. Localized business disruptions may occur in low-lying areas.