Weather – the dry or wet season?

The dry season (May to November) is the easiest time to travel, as then you are unlikely to meet rain and can expect clear blue skies. This is ideal if this is your first trip to Africa, or if seeing lots of big game is top of your wish-list.

Within this, you'll find June–August the coolest, and then from September onwards the heat gradually builds up. Note that where the altitude is relatively low – like the Luangwa, the Lower Zambezi Valley or Lake Tanganyika – the temperature is always higher. These places, especially, can get very hot towards the end of October, and occasions of over 40°C in the shade in the middle of the day have earned October the tag of 'suicide month' amongst the locals.

November is a variable month, but many days can be cooler than October, as the gathering clouds shield the earth from the sun. On some days these bring welcome showers; on others they simply build, and with them come tension and humidity. It's always an interesting month.

The wet season, December to March, is totally different, and the days can vary enormously from one to the next. Even within a day, skies will often change from sunny to cloudy within minutes and then back again. Downpours are usually heavy and short, and often in the late afternoon. Even in the lower valleys, temperatures are pleasant, rising to only around 30°C, and the nights only slightly cooler (typically down to perhaps 15°C). You will need a good waterproof for the rainy season, but it seldom rains for long enough to really stop you doing anything. Except travelling on bush roads…

Travelling

Travelling around Zambia in the dry season often has its challenges – but in the wet season it's a totally different game. Most untarred roads become quagmires; many are completely impassable. The rivers swell to bursting, often beyond, as their surging brown waters undermine trees and carry them downstream like pooh-sticks. Streams that were ankle-deep in October become potential rafting challenges. Many rural areas are cut off for a few months, so getting anywhere away from the main routes can be tricky.
However, if you are planning to fly into a national park for a safari, then the South Luangwa remains a possibility. Flights there are less frequent, but still run. It is the only one of Zambia's national parks to remain open. A few camps also welcome visitors and use the park's network of all-weather roads for driving safaris. One camp, based beside the park and up-river, runs canoeing and boating safaris. If you've often been to Africa in the dry season, then this is a fascinating time to visit – like being introduced to a different side of an old friend.

Vegetation

During the wet season, the foliage runs wild. The distinctive oxbow lagoons of the Luangwa and Lower Zambezi fill, while trees everywhere are deeply green. The open sandy plains become verdant meadows, often with shallow pools of water. It's a time of renewal, when a gentler light dapples Zambia's huge forests and areas of bush.

When the rains end, the leaves gradually dry and many eventually drop. More greys and browns appear, and good shade becomes harder to find. Eventually, by late September and October, most plants look dry and parched, coloured from straw-yellow to shrivelled brown.

Game

From the point of view of most herbivores, the wet season is a much more pleasant time. Those in national parks live in enormous salad bowls, with convenient pools of water nearby. It's a good time to have their young and eat themselves into good condition. Val and Bob Leyland were the first visitors for whom I ever organised a trip during the rains. On returning, they commented that 'having [previously] visited Africa last dry season, there's something special about seeing all the animals when they aren't struggling with thirst and a lack of vegetation… It gives a sense of luxuriance which isn't there in the dry season.'

Visiting South Luangwa in the wet season you will see game, but probably less of it. Last trip during the rains I went on two night drives. On the first we saw a good range of antelope (including some wonderful sightings of young animals), a few elephant and buffalo and a leopard at the end of the evening. The next we found a hyena on a kill, and later followed three lionesses hunting for several hours. The birding was consistently phenomenal, far better than during the dry season.

However, if game viewing is your priority, or this is one of your first trips to Africa, then the animals are much easier to spot when it's dry, as no thick vegetation obscures the view. Further, they are forced to congregate at well-known water points, like rivers, where they can be observed. Many more tracks are navigable in the bush, and so more areas can be explored by vehicle. So if you want to see large numbers of animals, then do come to Zambia in the dry season – and later rather than earlier if possible.
A few specific animal highlights include:

Feb–May
Most of the herbivores are in their best condition, having fed well on the lush vegetation.

May–Aug
Leopard are generally easier to see, as they come out more during the twilight hours. Later in the year they often come out later in the evening, waiting until it is cool.

Sept–Oct
Buffalo groups tend to amalgamate into larger, more spectacular herds. (They splinter again just before the rains.) Lion sights become more frequent, as they spend more time near the limited remaining water sources.

Oct–Dec
Crocodiles are nesting, and so are found on or near exposed sandbanks.

Nov
The great wildebeest migration masses on Liuwa Plain, in western Zambia. It's still accessible, but you'll need a small expedition to witness it.

Nov–Mar
Baby warthogs and impala start to appear in November, followed by most of the mammals that calve sometime during the rainy season.

Birdlife

The birdlife in Zambia is certainly best when the foliage is most dense, and the insects are thriving: in the wet season. Then many resident birds are nesting and in their bright, breeding plumage. This coincides to a large extent with the 'summer' period, from around October to March, when the Palaearctic migrants from the Northern Hemisphere are seen.

Certainly in terms of waterbirds – storks, herons, ducks, geese and the smaller waders – the rainy season (and just after) is an infinitely better time to visit. The birding calendar's highlights include:

Mar–July
Large breeding colonies of storks and herons gather to breed. The only sites I know are in the Nsefu sector of the South Luangwa National Park.

Aug–Oct
'Fishing parties' of herons, egrets and storks will arrive at pools as they dry up, to feed on the stranded fish.

Sept–Nov
Carmine bee-eaters form large nesting colonies in the soft sand of vertical riverbanks.

Oct–Nov
Pennant-winged nightjars are in resplendent breeding plumage.

Nov–April
Most of the weavers are in breeding plumage.

Feb–April
Fire-crowned bishop birds, yellow-billed storks and the spectacular paradise whydahs have their breeding plumage on display.

Apr–June
Resident African skimmers are nesting.

Photography

I find the light clearest and most spectacular during the rainy season. Then the rains have washed the dust from the air, and the bright sunlight can contrast wonderfully with dark storm clouds. The vegetation's also greener and brighter, and the animals and birds often in better condition.

However, it will rain occasionally when you're trying to take shots, and the long periods of flat, grey light through clouds can be very disappointing. Sometimes it can seem as if you're waiting for the gods to grant you just a few minutes of stunning light, between the clouds. A more practical time is probably just after the rains, around April to June, when at least you are less likely to be interrupted by a shower.

The dry season's light is reliably good, if not quite as inspirational as that found during the rains. You are unlikely to encounter any clouds, and will get better sightings of game to photograph. Do try to shoot in the first and last few hours of the day, when the sun is low in the sky. During the rest of the day use a filter (perhaps a polariser) to guard against the sheer strength of the light leaving you with a film full of washed-out shots.

Other visitors

Virtually all of Zambia's tourists come during the dry season, and mostly from August to early October. Zambia's small camps and lodges ensure that it never feels busy, even when everywhere is full. (In fact, the country's capacity for tourism remains tiny compared with that of anywhere else in East or southern Africa.)

Most of those visiting outside of this season are cognoscenti, who visit early or late in the season – May to July or November – when the camps are quieter and often costs are lower. Meanwhile, only a handful of visitors come during the rains, from December to April. The camps that do open then will often be quiet for days. Their rates can be much lower, and they're often far more flexible about bringing children on safari.

Much of the blame for this 'glut or famine' of visitors lies with overseas tour operators. Many who advertise trips here just don't know Zambia well enough to organise trips in the rainy season, when there are fewer internal flights, and the connections can be more awkward. It's much easier for them to make blanket generalisations like 'it's not possible' or 'not interesting' or that 'you won't see any game' if you visit in the wet season. None of which is true – but most people don't know this in advance.

While the rains are not the ideal time for everybody's trip, they are a fascinating time to visit and should not be dismissed without serious thought.

Walking safaris

For safe and interesting walking, you need the foliage to be low so that you can see through the surrounding bush as easily as possible. This means that the dry season is certainly the best time for walking. Walking in the wet season, through shoulder-high grass, is possible – but I'd only go with a very experienced guide and it is harder than during the dry season. My favourite months for walking are June to September, as October can get hot on longer walks.