Storm Surge: What Coastal Communities in Africa Need to Know

A storm surge can raise sea levels by metres in minutes. For people living near the shore, that’s not just water — it’s a sudden, fast-moving threat that destroys homes, roads and livelihoods. If you live on the Gulf of Guinea, Mozambique Channel, or South Africa’s coast, understanding storm surge can save lives.

How a storm surge forms

Storm surge happens when strong winds and low pressure push seawater toward the shore. Big storms—like tropical cyclones in the Indian Ocean or intense coastal storms in the Atlantic—combine high tides with wind-driven water, piling the ocean on land. Shallow coastal shelves and narrow bays make surges worse. That’s why two places hit by the same storm can face very different flooding levels.

Look out for these immediate signs: sudden drop or rise in sea level, a loud rushing sound like a freight train, and fast-moving waves moving inland. Local weather services and national meteorological agencies issue surge warnings with expected heights and timing—treat those alerts seriously.

Simple steps to prepare and stay safe

Preparation matters. Start by knowing your flood risk: check maps from local authorities, ask neighbours if they’ve seen past surges, and learn evacuation routes. Keep an emergency bag with water, medicines, a torch, phone charger, important papers in a waterproof bag, and a battery radio. If you’re in a low-lying area, plan where to move—higher ground, a sturdy public building or a pre-arranged family shelter.

When a storm surge warning is issued, act quickly. Move people and livestock to higher ground early—don’t wait for official orders if water starts to rise. Turn off electricity and gas if you can do so safely. Avoid walking, driving, or wading through floodwater; six inches of moving water can knock you down, and deeper water can carry vehicles away.

After the surge, stay cautious. Floodwater hides sharp debris, open drains, and live wires. Use clean water only for drinking until authorities say otherwise. Report broken roads and damaged infrastructure to local officials. Community checks help: neighbours can share resources and watch for vulnerable people like the elderly or children.

Longer-term, communities can reduce risk with natural and built measures. Mangroves and coastal dunes absorb wave energy. Early warning systems, raised homes, and better drainage cut damage. Local leaders and NGOs often run community drills—join them and ask questions about evacuation plans and shelter locations.

Storm surge is sudden but predictable enough to prepare for. Know the local risks, get alerts, move early, and help neighbours. Those four actions cut harm and keep more people safe when the sea pushes in.