Depending on where you are, November sees the start of the short rains. Generally, the northern parks are good for game year-round and although the Serengeti receives rain, this means the wildebeest will be moving south across the plains to make the most of this moisture.
Tarangire National Park particularly hots up from November onwards with humidity joining the rains throughout summer but offers great game numbers. Kaskazi winds blow in from the north-east from November onwards which are relatively dry, helping to temper the intense humidity. To avoid the ranis, head down to Selous where the dry landscapes last until December.
November sees plenty of predators seeking out newborn herbivores as the rainy season starts, and fewer safari vehicles about which makes for a much more intimate game-viewing experience.
Zanzibar does receive significant rainfall which is extremely unpredictable but visibility is still good on the coast and the billfish marlin fishing season begins around the middle of the month.