1970

1970 Bhola cyclone

Bhola cyclone strikes East Pakistan at high tide

A cyclone of only moderate meteorological strength became the deadliest on record, because its surge arrived on the crest of high tide.

12 November 1970, at the crest of the tide

The cyclone reached the coast of East Pakistan — now Bangladesh — on 12 November 1970 while riding the crest of high tide. Its estimated maximum wind was about 100 knots, roughly 115 mph, with a central pressure of 950–960 hPa.

The destructive passage and surge ran through the night of 12–13 November. The approximately 20-foot surge, rather than exceptional wind strength, caused most deaths as it crossed the low delta islands and tidal flats.

What the water took

Villages, crops, houses, livestock, roads and fishing infrastructure were swept away across coastal districts and offshore islands. In the 1,700-square-mile core of destruction, roughly 90 percent of housing was lost.

About 65 percent of southern East Pakistan's inland and marine fishing capacity was destroyed. The World Bank put immediate crop damage at about $63 million in 1970 dollars.

A death toll nobody can close

No reliable final registry was possible. The World Meteorological Organization recognizes Bhola as the highest-mortality tropical cyclone on record while emphasizing that the count is uncertain, giving a range of 300,000–500,000.

A later epidemiological survey established a minimum of 224,000 and found mean mortality of 16.5 percent in its survey area. In the worst-hit part of Tazumuddin, that survey found 46.3 percent of the population had died.

Sources

Researched 23 Aug 2026 9 sources 2 audit passes Date corrected

How this was checked

Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →

Date corrected. The research places this at 1970-11-12.

What the sources leave uncertain

The landfall is conventionally dated November 12, but the destructive passage and surge extended through the night of November 12–13.
No reliable final death registry was possible. WMO gives 300,000–500,000 as the broad range but formally records approximately 300,000 for its mortality-extreme evaluation; an epidemiological survey established a minimum estimate of 224,000.
Storm-intensity estimates vary by observing agency and later reconstruction. The best-supported scholarly estimate is about 100 knots with a central pressure of 950–960 hPa.
Inflation-adjusted damage equivalents vary by base year and method; retain the sourced 1970-dollar estimate rather than presenting a 2020 conversion as timeless.