El Niño in South Africa: 7 Surprising Facts About the Summer Ahead
From ocean temperatures thousands of kilometres away to the science of sweating, there's more to a hot South African summer than meets the eye.
If you thought last summer was hot, you might want to keep that water bottle close.
South Africa's weather forecasters are warning that a very strong El Niño could bring hotter, drier conditions across much of the country during the 2026/27 summer.
But here's the interesting part: El Niño isn't simply another name for hot weather. It's a remarkable climate phenomenon that begins in the Pacific Ocean and can influence everything from rainfall in Southern Africa to how we prepare for a summer outdoors.
And when the temperature climbs, our bodies have a few surprises of their own.
Here are seven things you might not know.
1. El Niño explains only about 30% of Southern Africa's rainfall variability
El Niño has a reputation for bringing drought to Southern Africa. And while drier conditions are often associated with it, the relationship isn't nearly as predictable as you might think.
According to the South African Weather Service (SAWS), El Niño accounts for only around 30% of the region's rainfall variability.
That means other weather systems and atmospheric conditions have a major say in how much rain actually falls.
A fascinating example is the powerful 1997/98 El Niño. Despite being one of the strongest on record, parts of South Africa experienced abundant rainfall.
So while forecasters may be predicting a dry summer, El Niño doesn't automatically mean drought.
2. The weather in South Africa can be influenced by ocean temperatures more than 10,000 kilometres away
El Niño begins when surface waters in the central and eastern tropical Pacific Ocean become unusually warm.
That warming changes the movement of air and moisture through the atmosphere, influencing weather patterns around the globe.
Think of it as a chain reaction: a relatively small shift in ocean temperatures can alter atmospheric circulation across enormous distances.
It's a reminder of just how interconnected our planet's climate systems really are.
3. Your body can actually train itself to handle heat better
Ever noticed how the first really hot days of summer feel particularly uncomfortable, but a few weeks later the same temperature seems more manageable?
There's science behind that.
Through a process called heat acclimatisation, your body gradually adapts to repeated heat exposure.
You begin sweating earlier, your cardiovascular system works more efficiently in the heat, and your sweat becomes less salty as your body gets better at conserving sodium.
Many of these adaptations develop over approximately 7–14 days of gradual exposure.
There's a catch, though: acclimatisation doesn't mean you're immune to heat-related illness, and it doesn't eliminate the need to replace fluids.
4. Two people doing the same workout can lose dramatically different amounts of sweat
You might assume that two people running the same route, at the same pace, in the same weather would have similar hydration needs.
Not necessarily.
Research shows that sweat rates during exercise can vary enormously, depending on body size, fitness, exercise intensity, temperature, humidity and individual physiology.
Some people may lose less than half a litre per hour, while others can lose more than two litres.
The amount of sodium lost in sweat also differs considerably between individuals.
This is why a one-size-fits-all approach to hydration doesn't always make sense, particularly during prolonged exercise.
5. Sweat actually becomes less salty as you adapt to heat
Here's a particularly clever feature of the human body.
When you first start exercising regularly in hot conditions, your sweat can contain relatively high concentrations of sodium.
As your body becomes acclimatised, your sweat glands get better at reabsorbing sodium before it reaches the skin.
The result? You may sweat more efficiently while losing less sodium per litre of sweat.
It's one of the body's natural ways of protecting its electrolyte balance.
Of course, sweating more can still mean substantial total fluid and sodium losses, especially during long periods of activity.
6. Drinking too much water can also be a problem
We hear plenty about dehydration, but far less about the opposite problem: overhydration.
During prolonged endurance exercise, drinking excessive amounts of fluid can dilute the sodium concentration in the blood, potentially causing a condition called exercise-associated hyponatraemia.
It's uncommon in everyday situations, but it is a recognised risk in endurance events.
The lesson isn't to drink less water. It's that hydration is about balance, not simply drinking as much as possible.
For most normal daily activities, water and regular meals are sufficient. During prolonged exercise or heavy sweating, individual fluid and electrolyte losses become more relevant.
7. Cape Town and Johannesburg don't necessarily experience El Niño in the same way
El Niño's effects vary significantly across South Africa.
Much of the country's interior receives most of its rainfall during summer, making it particularly sensitive to changes in summer rainfall patterns.
Cape Town and much of the Western Cape, however, receive most of their rain during winter.
This means a forecast for a drier summer across Southern Africa doesn't translate into exactly the same implications for every region.
It's another reason to pay attention to regional forecasts rather than assuming that El Niño affects the entire country equally.
What does all this mean for staying hydrated this summer?
The interesting thing about hydration is that our needs aren't fixed.
They change depending on the weather, how active we are, how much we sweat and how accustomed we are to the heat.
Water remains the best starting point for everyday hydration. But during prolonged exercise, outdoor activities or periods of heavy sweating, replacing lost electrolytes may also be beneficial.
That's where Revite Vit-T-Go can fit into your summer routine. With a combination of electrolytes and vitamins in convenient individual sachets, it's an easy option to keep in your gym bag, travel bag or desk drawer.
A little knowledge goes a long way
We can't control El Niño, and we certainly can't control the South African summer.
But understanding how our climate works, how our bodies respond to heat and why hydration needs differ from person to person can help us make smarter choices.
Here's to a summer of staying curious, staying active and staying hydrated.