The 1970 Bhola cyclone was a devastating tropical cyclone that struck East Pakistan and India's West Bengal on November 3, 1970. It remains the deadliest tropical cyclone ever recorded and one of the deadliest natural disasters. At least 500,000 people lost their lives in the storm, primarily as a result of the storm surge that flooded much of the low-lying islands of the Ganges Delta. This cyclone was the sixth cyclonic storm of the 1970 North Indian Ocean cyclone season, and also the season's strongest.

The cyclone formed over the central Bay of Bengal on November 8, and traveled northward, intensifying as it did so. It reached its peak with winds of 185 km/h (115 mph) on November 11 and made landfall on the coast of East Pakistan (now Bangladesh) on the following afternoon. The storm surge devastated many of the offshore islands, wiping out villages and destroying crops throughout the region. In the most severely affected Upazila, Tazumuddin, over 45% of the population of 167,000 was killed by the storm.

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