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Summer in Kuwait is characterized by large amounts of dust and sand, usually raised and deflated by the dry north-westerlies. The prerequisites for the suspension of dust particles in the air are:

1. aridity of land surface,
2. the presence of unconsolidated surface formations,
3. moderate wind velocity to invoke deflation,
4. atmospheric instability with extensive vertical movement of the air; this may be attributed in Kuwait to intensive heating of the ground surface during day time.

This study aims at expounding the relationship between wind velocity and directions on one hand, and the prevalence of aerial dust particles that reduce visibility on the other. It is based on data compiled throughout the decade extending from 1969 t0 1978, comprising hourly records (from 0600 to 1800) for the months May, June, July and August, in addition to statistics related to wind speed and direction.

The study has revealed the following:

1. Out of the total number of hours of 15990, some 27% were characterized by dust suspension. This percentage increased to 34% in July.
2. Sixty six per cent of the dust hours recorded during the summer months from May to August was accompanied by wind velocities ranging between 17 to 28 m.p.h.
3. The prevailing northwesterly was associated with 88% of the recorded dust hours in June, July and August.
4. Visibility was reduced to less than four kilometers in 48% of the recorded dust hours in June and July. In sixteen per cent of which visibility was even reduced to less than one kilometer.
5. The association between wind velocity and dust formation was also quite evident. The frequency of dust hours increased gradually according to wind speed from 7% related to wind velocity of less than 17 m.p.h., to 97% associated with wind speeds ranging from 29 to 33 m.p.h., to 100% with wind speeds exceeding 34 m.p.h.
6. The reduction of visibility followed a similar pattern. Probabilities for the deterioration of visibility in June and July to less than four kilometers were 47% with wind speeds ranging between 23 to 28 m.p.h. This rose to 77% with wind speeds between 29 to 33 m.p.h., and event to 100% when wind speed reached more than 34 m.p.h.