(Yasuyoshi Chibayasuyoshi/AFP/Getty Images)

It’s the first official day of the Olympics, which kick off with grand Opening Ceremonies Friday night in Rio de Janeiro. No other city in South America has ever hosted the Summer Olympics, which certainly makes sense. They are held during South America’s winter.

So yes, it’s wintertime in Rio. Break out the Speedo.

No really! Break it out. Rio de Janeiro is located along the east coast of Brazil — the part that sticks out pretty far into the Atlantic Ocean — at a latitude of 23 degrees south, which means it’s basically tropical. That is the Tropic of Capricorn.

To put that into perspective, there’s no location in the United States. that intersects with 23 degrees north, the Tropic of Cancer, but Rio’s August climate is very similar to that of Miami during winter.

This is all good news. Winter is Rio’s dry season — it’s less hot, less humid and much less rainy. The average high temperature in August is 78 degrees (although it has reached a record of 102) and the average low is 66 degrees. Arguably, this might be the most comfortable Summer Olympics since 2000, when it was held during the fall in Sydney.

However, Rio is also subject to microclimates, which means weather could actually vary between Olympic venues. Microclimate tend to set up in mountainous areas and locations next to oceans. Rio happens to be both of those, combined. Think San Francisco, where the temperature can be 55 degrees along the coast and 80 degrees in East Bay.

Some outdoor events could be affected by strong sea breezes if they happen to set up. This is when temperatures warm over land more than over the ocean, and low pressure results. Winds flow from high pressure to low pressure, and thus — the sea breeze begins. It’s cool and it’s moist, but it might prove to be annoying for outdoor sports like golf and rowing.

Of course, Brazil is not simply a coastal country. It’s also home to the Amazon rain forest — the largest, most biologically diverse rain forest in the world. It accounts for 25 percent of Earth’s carbon dioxide absorption, Climate Central reports, although its ability to scour greenhouse gas out of the atmosphere is quickly dwindling.

“Deforestation rates in the Amazon have decreased in the last decade, but the total area continues to decline, with an area the size of Delaware lost in each of the last 5 years,” Climate Central writes. “Global and regional climate models indicate the Amazon will become drier and hotter through the century, further stressing the rainforest.”