A new frontal system driven by an atmospheric river will bring intense rain and snow to central-south Chile this Friday [1], [2].
This weather event poses a significant risk to infrastructure and safety in the precordillera sectors, where the combination of high moisture and rapid movement can lead to flash flooding and landslides.
Arlette Chacón, a meteorologist with the program "Buenos Días a Todos" on TVN Chile, said the incoming system is associated with an atmospheric river, which acts as a conveyor belt transporting vast amounts of moisture from the ocean to the mainland [1], [2].
Forecasters expect accumulated precipitation to exceed 90mm in certain areas [1]. This intensity of rainfall is expected to impact four regions, including Valparaíso, O’Higgins, Maule, and Bío-Bío [2]. The system is characterized by its rapid advance, which increases the likelihood of sudden and severe weather shifts.
In addition to heavy rains, the system will trigger strong winds and snowfall in higher elevations [1]. The precordillera zones are particularly vulnerable due to the volume of water expected to fall over a short period [2]. Local authorities typically monitor these regions for potential soil saturation and runoff risks during such events.
Weather officials said the atmospheric river is considered extreme, which contributes to the high volume of precipitation [2]. Residents in the affected regions are advised to prepare for potential disruptions to travel and utility services as the storm moves through the central-south corridor this week [1], [2].
“Accumulated precipitation to exceed 90mm”
The arrival of an 'extreme' atmospheric river indicates a high-density moisture corridor that can overwhelm local drainage systems. Because the system is moving rapidly and targeting four specific regions, the concentrated rainfall of over 90mm increases the probability of saturated soils, which often leads to landslides in the precordillera regions of Chile.
