Hi,

I am considering a trip to South America in mid- to late-August. What are some destinations that you would recommend for this time of year?

Thank you.

Most South American countries have diverse climates within their borders. So you just have to choose the right spot in each country to get the most out of your visit depending on the time of year. Some examples:
For skiing: Chile and Argentina
For desert views and stunning scenery: Northern Chile and Northern Argentina
For dry season and best time to visit: Cusco, Machu Picchu, highlands and salt flats of Bolivia.

Thank you for your help. Will northern Chile/Argentina be cold that time of year?

No, the further north you go the warmer it is. Nights can be cold though, depending on where you are. You might look into the area around Salta which offers varied and interesting scenery and its own wine production. Or San Pedro de Atacama in Chile in the driest desert in the world.

Are there any places you can go to in South America in July/August that are warm and have a beach? 80 degrees or higher?

Probably somewhere on the Colombian or Venezuelan coast (Isla Margarita), the far north of Perú, or coastal Ecuador.

Thank you.

I don't know about the climate in many of the areas of South America, but I do know from previous visits (7xs to Brasil and 4x's to Argentina and 1 visit to Chile and to Peru) that late September onward into October is as fabulous time to visit. It's the beginning of spring in these areas; thus one did not need to have any heavy clothing so to speak and could be outside to enjoy all that these areas afford natives as well as visitors alike.

When I was in Machu Picchu and Lima and Cusco-- I did not wear a jacket. The same went in Santiago, Chile and parts around the lakes and other parts of this country.

Spring and early autumn I would say are the better times to experience South America although the first writer made some valid and salient points to which I solidly agree.

Unless you want to end like a popsicle I would advise you to stay clear of middle Chile. August is the coldest month in Santiago, to the point that we say "You survived August" on its yearly passing, wet, damp and freezing cold.
Santiago, Coast and South start on warming up middle September, but you still need a wind jacket at night.

The North of Chile is warm most of year, so that's not a problem. The same for Peru on the lower cities, high cities are still cold. Lima is pretty foggy in the morning but clear in the afternoon, with a humid weather.

Remember than we change the Stations at the same time but opposite. Summer-Winter, Fall-Spring