The weather tends to dictate when it is best to visit. The wet season (mainly April to October) is not the best time to visit due to the wind, rain and high humidity. November to January are the coolest and driest months.
From a birding point of view, the migration seasons are possibly the best time to visit. The autumn migration is often over-looked because it coincides with the rainy season but the spring migration (February to April) can be fantastic. To see weavers and bishops in their spectacular breeding plumage it is best to visit before mid-November; and this is also a better time of year for butterflies and amphibians. In January and February conditions for seeing birds are often at their best, as grasses and other vegetation have died back, allowing better views into fields; and birds tend to concentrate around the few remaining wetlands.