South America: Adverse weather forecast across parts of northeastern Argentina, southern Brazil, southern Paraguay, and Uruguay through at least Oct. 26

Severe weather associated with an extratropical cyclone system is forecast across parts of far northeastern Argentina, southern Brazil, southern Paraguay, and much of Uruguay through at least Oct. 26. Heavy rainfall, thunderstorms, and strong winds are expected across the region over the coming days. Heavy downpours could trigger flooding in low-lying areas in affected regions and landslides on unstable slopes. Strong winds may cause power outages and property damage.

As of early Oct. 24, Argentina's National Meteorological Service (SMN) has issued yellow thunderstorm warnings (the lowest level on a three-tier scale) across Misiones, much of Corrientes, and parts of southeastern Chaco provinces.

Brazil's National Institute of Meteorology (INMET) has issued a red storm warning (the highest level on a three-tier scale) across parts of southwestern Parana, central, eastern, and northern Rio Grande do Sul, and western Santa Catarina states. Rainfall totals of over 6 cm (2.4 inches) per hour or 10 cm (4 inches) per day are expected in the red warning area, as well as winds between over 100 kph (62 mph) and possible hail storms. Orange storm warnings are in place across the rest of the affected area in southern Brazil.

Paraguay's Directorate of Meteorology and Hydrology has issued a special weather bulletin for storms across southern parts of the country Oct. 24. Rainfall totals of 3-6 cm (1.2-2.4 inches) and winds gusting up to 120 kph (75 mph) are expected across the affected area, as well as possible hail. A short-term warning for moderate-to-strong rainfall with thunderstorms, moderate-to-strong wind gusts, and occasional hail has been issued across southern parts of the Eastern Region early Oct. 24.

The Uruguayan Institute of Meteorology (INUMET) has issued a public notice warning of very strong storms and heavy rainfall spreading from the west coast across much of the country Oct. 24. Strong winds are expected to intensify from the south late Oct. 24 before subsiding Oct. 26, with eastern, south-central, and southwestern areas expected to be worst affected.

Officials could update and possibly extend the coverage of weather alerts over the coming days.

The storms could produce rounds of heavy precipitation, strong winds, and isolated thunderstorm activity in the affected area. Sustained heavy rainfall could trigger flash and areal flooding. Such flooding is possible in low-lying communities near watercourses and other large bodies of water and in urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of large reservoirs may be subject to flash flooding after relatively short periods of intense rainfall.

The severe weather will likely contribute to transport disruptions across parts of the impacted region. Traffic and commercial trucking delays might occur along regional highways. Flooding downpours could inundate some low-lying roads in areas with poor drainage. Strong winds might also pose a hazard to high-profile vehicles. Hazardous weather conditions might cause flight delays and cancellations at regional airports.