What if a Nuclear Bomb Hit Mexico City?

Mexico · Population 9,209,000 · Density 6,000/km²

About Mexico City

The capital of Mexico and the largest city in North America by population, with a metro area of over 21 million.

Below are four scenario calculations using historical and modern nuclear weapons. Each row shows the radius of an effect zone in kilometers and a rough order-of-magnitude estimate of people inside that zone, derived from the city's urban population density. Numbers are educational approximations — see the methodology page for the underlying formulas.

Little Boy on Mexico City (15 kt)

USA · 1945 · Hiroshima bomb

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)0.43 km~3,459
Severe blast (20 PSI, ~98% fatal)1.18 km~22,176
Moderate blast (5 PSI, ~50% fatal)2.52 km~46,647
Light blast (1 PSI, glass injuries)7.16 km~42,358
3rd-degree thermal burns2.03 km

W76 on Mexico City (100 kt)

USA · 1978 · Common SLBM warhead

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)0.91 km~15,777
Severe blast (20 PSI, ~98% fatal)2.20 km~73,888
Moderate blast (5 PSI, ~50% fatal)4.71 km~163,156
Light blast (1 PSI, glass injuries)13.39 km~148,157
3rd-degree thermal burns4.43 km

Castle Bravo on Mexico City (15 Mt)

USA · 1954 · Most powerful US nuclear test

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)6.79 km~868,781
Severe blast (20 PSI, ~98% fatal)11.51 km~1,579,389
Moderate blast (5 PSI, ~50% fatal)24.60 km~4,454,754
Light blast (1 PSI, glass injuries)69.98 km~4,045,201
3rd-degree thermal burns34.54 km

Tsar Bomba on Mexico City (50 Mt)

USSR · 1961 · Largest nuclear weapon ever tested

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)10.99 km~2,276,214
Severe blast (20 PSI, ~98% fatal)17.13 km~3,143,065
Moderate blast (5 PSI, ~50% fatal)36.60 km~9,861,062
Light blast (1 PSI, glass injuries)104.12 km~8,954,475
3rd-degree thermal burns56.58 km

Limitations

These estimates assume an idealized air burst over the city center, uniform population density, and no advance warning or sheltering. Real-world casualties would depend on:

  • Time of day (population is concentrated downtown during business hours)
  • Sheltering and basements (subway systems can reduce casualties significantly)
  • Building construction (reinforced steel/concrete vs. wood-frame)
  • Weather and atmospheric conditions
  • Detonation altitude (air burst vs. surface burst)
  • Subsequent fallout and infrastructure collapse

Other City Scenarios

FAQ

What would happen if a nuclear bomb hit Mexico City?

Mexico City has approximately 9,209,000 people and an urban density around 6,000 per km². A Hiroshima-yield warhead (15 kt Little Boy) detonated over Mexico City would produce a moderate blast radius of about 2.5 km, with an estimated 25,635 immediate fatalities in the severe-blast zone. A modern strategic warhead (W76, 100 kt) would extend the moderate-damage zone to roughly 4.7 km with thermal burns reaching 4.4 km. Run the interactive simulator above to see the exact zones overlaid on the map.

How many people would die in Mexico City from a nuclear strike?

A 100 kt W76 strategic warhead air-burst over Mexico City could cause an estimated 252,821 immediate fatalities and around 148,157 additional injured. For comparison, a 50 Mt Tsar Bomba — the largest weapon ever tested — would put roughly 204,341,495 people inside the 1 PSI light-blast zone alone. Real casualties depend strongly on time of day, sheltering, weather, and altitude of detonation.

What is the blast radius of a nuclear bomb over Mexico City?

For a 100 kt strategic warhead over Mexico City: fireball radius 0.91 km, severe blast (20 PSI) 2.20 km, moderate blast (5 PSI) 4.71 km, light blast (1 PSI) 13.39 km, third-degree thermal burns 4.43 km. Larger yields scale these radii roughly as the cube root of yield for blast and the 0.41 power for thermal effects.

Is Mexico City a likely nuclear target?

This is an educational simulator and does not assess threat probability. Mexico City is one of the world's most prominent cities in North America, which is why we feature it as a scenario. The purpose of these visualizations is to convey the humanitarian scale of nuclear weapons — not to make any operational claim.

See also: full Weapons Database (45+ entries) · Scientific methodology · Data sources.