Map from Google - Victoria_Falls

In the area of Victoria Falls, the climate is sub-tropical, with a mild and dry winter from mid-May to mid-August (during which, however, the nights are cold), and a hot, muggy and rainy summer from mid-November to mid-March. The rains occur in the form of downpour or thunderstorm. Between September and November, before the rainy season, there is a hot period, in fact the hottest of the year, in which the temperature easily reaches 35 °C (95 °F), and sometimes even 40 °C (104 °F), even though the humidity is not as high as in summer. October is the hottest month of the year. On the contrary, during winter, when during the day the weather is nice, the night temperature may approach freezing (0 °C or 32 °F).
Here are the average temperatures.
Average temperatures - Victoria Falls
Victoria FallsJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)18181714966813171818
Max (°C)302930292725252832333230
Min (°F)646463574843434655636464
Max (°F)868486848177778290919086

Precipitation is not very abundant, since it amounts to 660 millimetres (26 inches) per year, but it is quite abundant from December to February, while it almost never rains from May to September.
Here is the average precipitation.
Average precipitation - Victoria Falls
Victoria FallsJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec. (mm)1701257025310022565175661
Prec. (in)

The amount of sunshine in the Victoria Falls area is very good from April to October, ie the dry season, while it is acceptable in the rainy season, in which, between a shower and the other, the sun shines.

100 metres deep and 1,700 metres (5,600 ft) wide, the Victoria Falls, probably the most spectacular in the world, are located on the border between Zambia and Zimbabwe, at about 900 metres (3,000 feet) above sea level, and are formed by the water of the Zambezi River. The altitude tempers the heat in the hot season (September to March), and makes the nights cold in the period mid-May to mid-August. The falls can be accessed from both countries, although the most equipped part is that of Zimbabwe. The falls are a UNESCO World Heritage Site.
The season of high river discharge runs from February to May, with a spike in April. The river reaches its minimum flow in November, when it becomes ten times smaller than in April. When the flow rate is highest, you cannot see some parts of the falls because of splash and mist, and it is difficult to take pictures. During the period in which the flow rate is lower, from October to December, the waterfall is divided into several streams, and some parts become dry. In December, the river begins to grow again, but in this period we are in the rainy season, with sultry heat and frequent afternoon showers.
The spray caused by the waterfalls exceed 400 metres (1,300 feet) in height, and are visible from a distance of 50 km (30 mi); they also feed a nearby rainforest.
The Victoria Falls National Park is home to a rich fauna, including elephants, giraffes and zebras.
You can raft the rapids produced by the waterfalls. There is also a natural waterhole, the "Devil's Pool", where someone swims, at least when the river flow rate is not at its highest, on the edge of the falls, however, this is a dangerous and not recommended activity.

Victoria Falls

When to go

The best time to visit the Victoria Falls goes from June to mid-August, being the coolest, as well as driest and sunniest, and when the river flow rate is halfway between the minimum and the maximum. It's better to be prepared for the night cold, and dress in layers, because during the day the air becomes mild or pleasantly warm. It can also be useful to bring a raincoat for the spray. From mid-August to mid-November, it's still the dry season, but it is a period in which the heat is getting more intense, while the river is getting drier.