Rain could return to central Chile from Sunday, October 18, with the arrival of a new extratropical cyclone. Following a week of heavy precipitation, wind and thunderstorms, the forecast also calls for showers and possible lightning over several days.
BioBioChile reported this based on a report by Pamela Henríquez, a meteorologist at Meteored. Publimetro carried the same forecast, based on the European ECMWF model (European Centre for Medium-Range Weather Forecasts).
There will be a respite before the change. Stable conditions are expected between this Thursday, October 15, and Saturday, October 17, with mild temperatures and variable cloud cover in central Chile.
According to Henríquez, Sunday's initial rainfall would be light and concentrated in inland areas of Valparaíso, the Metropolitan Region and O'Higgins. Rainfall totals would increase from Monday, October 19. Over the following days, the unsettled weather would gradually spread toward Maule, Ñuble and Biobío.
Some places could see at least five days of rain. The specialist identified Wednesday, October 21, and Thursday, October 22, as the rainiest period, with daily totals of up to 20 mm in Santiago, 28 mm in Talca and 34 mm in Chillán, depending on the day and location.
Publimetro added that cold air aloft, combined with the system's development, could favor showers and possible thunderstorms in parts of central Chile.
Henríquez urged caution regarding the figures. "It is still not possible to confirm the intensity or distribution of each episode," the meteorologist warned, although the outlook points to unsettled weather between October 18 and 23. As this is a medium-range forecast, rainfall totals and affected areas may change.
An extratropical, or midlatitude, cyclone is a low-pressure system that forms far from the tropics, generally between latitudes 30 and 60, a belt that includes much of Chile. It typically brings rain, wind and a higher freezing level as temperatures rise.
The event would follow an already exceptional month for the capital. As of this Thursday, the Quinta Normal station has recorded 108 millimeters in October, far above the 64.8 mm recorded in October 1987.
The sources consulted do not include official recommendations from the authorities for this new system. Meteored expects to update the forecast as Sunday, October 18, approaches.
