When to go all depends on what kind of experience you want at the falls themselves. High-water season is April through June, when it’s so loud you have to yell and the surrounding bush is thick with green vegetation—and you swear it’s raining upward. The downside? Sometimes the spray is so dense you can’t actually see the falls themselves. (Bring a raincoat or poncho, or rent one at the park entrance.) And your camera will get soaked after just a few snaps.
Want to river raft? Plan to be here during low water, late July to February; at the highest water, in April and May, no one runs trips.
Come September, the water level drops, the weather starts to get hot (90-plus degrees), and some of the falls even dry up. In fact, the whole landscape turns brownish. If you’re more interested in wildlife than water, September and October are your best bet: not only have watering holes dried up significantly (so animals tend to congregate near the river, where they can grab a drink), but the vegetation has turned sparse, making your Big Five easier to spot.
If there’s a quiet season, it’s the rainy season, November to March, when malaria poses a greater risk—and blue sky alternates with torrential downpours. On the three days around the full moon, you can enter the park at night, when the cascade is illuminated by moonlight—and sometimes creates spectacular moonbows.