Weather
Fiji has two seasons: the wet (rainy) season and the dry season. June is near the start of the dry season, which continues until October. It's sometimes called Fiji's winter, and although nights are cooler and you might need a light sweater, most travelers will still consider the weather warm in June. Rainfall is low, although not as low as July, which is the driest month.
Although temperatures are reasonably uniform year-round in Fiji, expect high temperatures of up to 80°F (27°C) in June, which is a few degrees cooler than at the height of the wet season. Humidity is also much lower during the dry season, which many travelers find more comfortable. The chance of cyclones is also meager in June, and while unseasonal storms can't be ruled out, you're unlikely to encounter them in June.
Crowds & Costs
The dry season is generally the height for travel to Fiji, and June is the start of the peak season for travel which means flights and accommodation should be booked in advance. However, it's generally less busy than July and August, when Australians and New Zealanders and then Europeans and North Americans flock to Fiji during their winter/summer school vacations. June is an ideal time to come if you want to make the most of the good weather but avoid the crowds and elevated prices as much as possible.
Chat with a local specialist who can help organize your trip.
Where to Go
Fiji's third-largest island, Taveuni, is an excellent destination for travelers with a range of active interests. As well as beautiful beaches, this island has an array of nature-focused outdoor activities. About a third of the island comprises the Bouma National Heritage Park. Hike to impressive Tavoro Falls, snorkel or dive to see the soft corals in the Somosomo Strait between Vanua Levu and Taveuni, or do the Lavena Coastal Walk along the south coast, past black-sand beaches and lush tropical forest.
With good weather unlikely to disrupt carefully laid travel plans, June is an ideal time for adventurous travelers to visit some of Fiji's outer islands. Like the Lau Islands, 60-odd islands on Fiji's eastern boundary, close to Tonga. Very few travelers make it out here, even in peak season. Enjoy snorkeling in pristine waters (take your own gear), learn about the local culture at a village homestay, or take a guided hike of the island of Vanua Balavu.
What to Do
June is a great time to go hiking in Fiji because the conditions will be dry and comfortable without being too hot. As well as Taveuni (see above), there are a number of options of what to see and do on Viti Levu. The moderate hike to the summit of Mount Batilamu in Koroyanitu National Heritage Park takes about six hours, and there are great views from the top. The more challenging four-day Viti Levu cross-island hike takes in forests, grasslands, streams, and waterfalls, and you'll spend the nights in villages.
June is also a good month for diving and snorkeling as the sea is calm and clear, although divers usually don wetsuits. Dive with sharks at Beqa Lagoon, south of Viti Levu; with manta rays in the Yasawa Islands; or the amazing Great Astrolabe Reef off Kadavu Island. Can't dive, won't dive? Snorkeling can also be done at many places offering diving and from the beaches in many sites, such as the Mamanuca Islands.