Simoom is a strong, dry, dust-laden wind. The word is generally used to describe a local wind that blows in the Sahara, Israel, Palestine, Jordan, Iraq, Syria, and the deserts of Arabian Peninsula. Its temperature may exceed 54 °C (129 °F) and the humidity may fall below 10%.

The name means "poison wind" and is given because the sudden onset of simoom may also cause heatstroke. This is attributed to the fact that the hot wind brings more heat to the body than can be disposed of by the evaporation of perspiration.

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