A strong storm system will slam into Chile during the beginning of the week, bring much needed moisture to the drought-stricken region. Through the middle of the week, this storm will move to the east bringing the threat for heavy rain to northern Argentina, Paraguay, Uruguay and southern Brazil.
While impacts from this system will begin to be felt across southern Chile on Monday, the brunt of the storm will not arrive until Tuesday and Wednesday as heavy rain and wind moves onshore.
The heaviest and most widespread rain will fall from Santiago on south. A few showers could advance as far north as La Serena, but any precipitation this far north should be minimal.
In Santiago, rainfall Tuesday and Wednesday is expected to be in excess 25 mm (1 inch) and could reach 50 mm (2 inches) along the base of the Andes. This will be enough rain to cancel many outdoor activities and could lead to isolated flooding as normally dry streams fill with water.
From January through September, rainfall in Santiago has been less than half of normal. Dry conditions have contributed to a drought that has been in place across Chile for over a year.
AccuWeather Meteorologist Rob Miller states "While this rain will help to bring temporary relief in drought conditions and add snowpack in the mountains, it will not be enough to eliminate the drought."
While beginning high early in the week, snow levels around Santiago will fall to 1,500-2,000 meters (about 5,000-6,500 feet) by Wednesday. This will bring a heavy, late-season snow to the many ski resorts across the Andes. In elevations above 3,000 meters (10,000 ft), where precipitation is primarily snow, accumulations will likely exceed a meter (3 feet).
Impacts will not be limited to Chile, but rather, will spread into central and eastern South America through the middle of the week bringing the threat for heavy rain and severe weather.
Showers and thunderstorms will develop across central and northern Argentina by Wednesday. Heavy rain and the threat for severe thunderstorms will develop in northern Argentina, eastern Paraguay, southeastern Brazil and Uruguay Wednesday night or on Thursday.