Weather
Bolivia, like many South American countries, is divided into several geographical zones, each of which has its own distinct climate. There is the high-altitude Andes in the west, with a climate similar to the Andean region of Peru, the lush hot and humid rainforest in the north, and the savanna region in the south and east, which is largely covered by the Gran Chaco and is predominantly semi-arid with little tree cover.
Andes
Sitting astride a mountain plateau at 11,942 feet (3,640 m) above sea level, La Paz gives a broad indication of what the weather is like in the Andes in general. In September, things are starting to get slightly warmer, with highs of 55°F (13°C) and lows of 32°F (-0°C). As the elevation increases, things get cooler, however, so you'll still need plenty of layers, a sweater, and a warm jacket if you're venturing up to Lake Titicaca or the Salar de Uyuni, where temperatures can drop as low as 28°F (-2°C).
Rainforest
The heat has been turned up in the Amazon with the arrival of spring, and September is the hottest month. Cobija, on the Brazilian border in the far north of the country, is broadly representative of the weather in the rainforest. While it is still dry season, making access by road easy and bumping up your chances of spotting wildlife, temperatures are now rising to 93°F (34°C), making things feel hot, steamy (and sweaty at times!). The rainy season is a way off yet, but you should be prepared for the odd shower or thunderstorm, with an average of seven rainy days in September.
Savanna
Abundant warm, dry weather makes September a great time to explore Bolivia's lowlands, with around eight hours of sunshine a day and an average of just five rainy days in the month. The conditions are ideal for outdoor activities such as hiking and mountain biking. Santa Cruz can be used as a benchmark for the region, with temperatures reaching up to 84°F (29°C), and still pleasantly warm lows of 66°F (19°C).
Crowds & Costs
Winter is coming to a close in September, and the crowds begin to ease up with the arrival of spring. This is a relatively peaceful time to visit (especially the latter half of the month), with largely dry, sunny days and slowly increasing temperatures taking the chill off the Altiplano. Despite a slight increase in rain, it's still a great month for adventure sports. And as visitor numbers begin to drop, so too do room rates and the cost of guided tours. However, you'll need to book ahead if you plan to tie in your trip with the Fiesta de San Roque in Tarija on the first Sunday of the month.
Where to Go
Andes
A city with altitude and a breathtaking mountain backdrop, La Paz is the gateway to the Andes. Spend a day or two here to acclimate before striking out into the llama-dotted wilds of the Altiplano. With the weather still largely dry and temperatures gently rising, this is a wonderful time to take a 4x4 tour of the Salar de Uyuni's surreally beautiful white salt flats and the hot springs and flamingo-filled lakes close by. Plus, good deals should be available now that the crowds have thinned. Lake Titicaca holds plenty of appeal this month, too, with slightly warmer—and still bright—days for hiking and boat trips over to the mysterious ruins on Isla del Sol, the birthplace of the Incas.
Rainforest
It's getting hot in the Amazon, but if you can keep your cool, September is a fantastic time to come in many respects. There are far fewer travelers than in July and August, meaning better deals at ecolodges and guided hiking tours and boat trips. Odd shower and storm aside, the weather is still nice and dry, too, upping your chances of face-to-face wildlife encounters in the likes of the vast Madidi National Park. Great springboards for accessing the jungle include Trinidad, with its attractive plaza and colonnaded streets, and ever so chilled Rurrenabaque, where you can flop on a hammock before jungle and pampas tours.
Savanna
September is a peaceful time to visit Bolivia's savanna region, with few crowds and largely dry and warm conditions. Devote a day or two to the museums, food, and nightlife of easy-going Santa Cruz, which is well placed for a road trip of the Jesuit missions in nearby Chiquitania. Relaxed Samaipata has a hippie vibe, spectacularly lush mountain surrounds, and proximity to the wildlife-rich Amboró National Park. Much further south, close to the border with Argentina, Tarija is a good base for discovering the high-altitude Valle de la Concepción, home to some of the world's highest vineyards.
Chat with a local specialist who can help organize your trip.
What to Do
Andes
Bolivia's highlands are a delight to explore in the quieter month of September, and the crisp, bright weather on the Altiplano is an added boon. Conditions are just right for outdoor adventures, whether you want to up the thrill (and fear) factor on the road from La Paz to Coroico through the forest-cloaked mountains of the Yungas or go off the radar, hiking a multi-day trail through the peaks of the spectacular Cordillera Real.
For more of a cultural focus, factor in a trip to the former silver mining town of Potosí, once the economic heart of Spain's empire and now a Unesco World Heritage site. Or head to the country's sugar-white capital, Sucre, for a feast of museums and colonial architecture.
Rainforest
The heat is cranking up in the Bolivian Amazon now. So be sure to allow ample time for swinging in a hammock and cooling down pre- or post-tour at an ecotourism hub like Rurrenabaque, a relaxed base for slow boat tours along the Río Beni and a springboard for exploring the biodiverse Madidi National Park (September is still a great month for wildlife sightings as the dry weather lingers).
Here you can canoe through the wilds, hook onto a multi-day trek or go rafting, keeping an eye out for howler monkeys, pink river dolphins, macaws, and capybaras. With some colonial flair, Trinidad is a great alternative for jungle hiking and boat trips along the Río Mamoré to the Brazilian border.
Savanna
If you are looking for more of an offbeat adventure, Bolivia's lesser-explored savanna is the go-to region, and September is a terrific month for a cross-country trip. Perhaps devote a day or two to Santa Cruz, a characterful city with colonial architecture, an exciting food scene, and attractions swinging from botanical gardens to a regional history museum.
In the latter, you can get the inside scoop on the Jesuit missions in nearby Chiquitano before heading out to see the restored churches for real. This is a fine month for hiking in the lush jungle wilds of the Amboró National Park, home to the rare spectacled bear. Or opt for vineyard tours and wine tasting instead in the high-altitude Valle de la Concepción, using Tarija as your base.
Events in September
Fiesta de San Roque, Tarija. This fiesta in the wine-growing center of Tarija is the big one in September: eight days of solid partying, parades, music, dancing, and flamboyant costumes. It kicks off on the first Sunday of the month.
Virgen de Guadalupe, nationwide. Held in early September, this festival is an all-out celebration of Our Lady of Guadalupe, with folk dancing, music, feasting, and colorful costumed parades. It's at its party-loving best in capital Sucre.
Traveling to Bolivia in September? Check out these great itineraries
Bolivia & Atacama, Chile - 12 Days. Get ready for South America's extremes: the highest capital city, tradition-rich La Paz, the Salar de Uyuni, the world's largest salt flats, and one of the driest places on the plane—the Atacama Desert, full of otherworldly rock formations.
Bolivian Cities, Cloud Forests & Salt Flats- 9 Days. You will begin in the vibrant high-altitude city of La Paz, but be prepared for a lot more adventure: the heart-in-mouth mountain bike ride down the camino de muerte (road of death), the spellbinding cloud forests of Bolivia's Yungas region, and a visit to a community of coca farmers: not to mention time in the strange and vast salt flats of Salar de Uyuni.
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