Weather
Fiji is a tropical country with only two seasons (the wet and the dry). October is the end of the dry season, and temperatures, rainfall, and humidity won't be as high as during the rainy season.
Although temps are relatively uniform year-round in Fiji, expect high temperatures of up to 80°F (27°C) in October. The chance of cyclones is low, too, although the threat of unseasonal storms can't be ruled out entirely. Keep an eye on the weather forecasts to ensure you won't be in the path of an early cyclone in October.
Crowds & Costs
October is the shoulder season for travel to Fiji, between the peak of the dry season and the low of the wet season. There will be a few travelers around but not as many as in July and August. You're more likely to get a deal on flights and accommodation if you book far enough in advance. Book early if you have particular preferences or restrictions, but this isn't as important as during the peak season.
Chat with a local specialist who can help organize your trip.
Where to Go
If Diwali falls in October during your visit, you might like to consider visiting a town or city with a prominent Indo-Fijian community, such as Nadi or Suva. Nadi is home to the largest Hindu temple in the Pacific, the Sri Siva Subramaniya Temple, in the South Indian style with a decorative gopuram (tower). It's especially lively during Diwali, particularly after dark. (Outside of Diwali. you can visit the temple between dawn and dusk.) Many resorts also have their own Diwali celebrations.
You'll most likely spend much of your time in Fiji at or near a beach. But if you get a day or half-day of rain at the end of the dry season, take a break from the beach and visit the beautiful Garden of the Sleeping Giant. At the foot of the Nausori Highlands just inland from Nadi, these landscaped gardens have boardwalks through the rainforest and around 40 species of tropical orchids. They were once a private collection but are now open to the public.
What to Do
While many travelers come to Fiji to stay in luxurious resorts, a fun and interesting alternative (or addition) is to stay in a small local homestay in a village. These are dotted around the country, including Viti Levu, the Mamanuca Islands, and the Yasawa Islands. Learn about everyday life in rural Fiji and get to know the local people in a way impossible from a regular hotel. Living quarters are usually basic but clean and comfortable, and activities typically include a village tour.
Another activity that can be enjoyed either as part of a homestay or separately is being part of a traditional kava ceremony. Guests sit in a circle on the floor around a central bowl, where kava—a lightly narcotic and sedative drink made from a crushed plant root—is prepared. It's a great way to learn about Fijian culture. Enjoy a Fijian cooking class instead if you're not into drinking or want to include the kids.
Events in October
Independence Week/Independence Day, nationwide. Independence Week in early October culminates in Independence Day on October 10. This holiday celebrates Fiji's independence from Britain in 1970 and is celebrated with cultural and religious events.
Diwali, nationwide. Diwali is a five-day Hindu festival celebrated in late October or early November by Fiji's Indo-Fijian community. This festival of lights is celebrated with fireworks and candlelight displays in homes and at temples. It's a public holiday across Fiji.