Posadas, Argentina

Weather Underground Forecast for Wednesday, May 16, 2012. No tropical development is expected for the tropical Atlantic Ocean on Wednesday as the beginning of the tropical season is still two weeks away. Instead, expect areas of strong thunderstorms to develop, with the strongest of these thunderstorms popping up in the western Caribbean Sea along the coast of Central America from Costa Rica through Belize and Guatemala. These thunderstorms will be strong enough to generate heavy rain that could trigger mudslides,e specially from Guatemala through Honduras.

Additional scattered showers and thunderstorms will develop in the normal areas of the Caribbean Sea south of Hispaniola and Puerto Rico.

In the Gulf of Mexico, a few thunderstorms will develop in the eastern gulf close to Florida. The rest of the gulf will remain mostly dry.

For South America, Atlantic moisture will remain in the Sao Paulo region, producing scattered showers and thunderstorms from Santa Catarina through Rio De Janeiro.

A high pressure system to the south will keep conditions dry for much of Argentina and Uruguay. The one exception to this will be south of Buenos Aires as a weak cold front moves through the area.

Meanwhile, a strong storm will slam into southern Chile, producing additional rain and high elevation snow south of Santiago.

Rio De Janeiro will rise into the mid-70s(F)/mid-20s(C), while Buenos Aires will see temperatures in the mid-60s(F)/upper 10s(C). Santiago, Chile will rise into the mid-60s(F)/upper 10s(C).