Let not the cyclones haunt us. Better care them away. Away from our minds. But we still have to be mindful of the facts about cyclones. The facts, however, remain that each year before the onset of the monsoon April 15 t July 15 and also after its withdrawal September 15 to December 15, there is always a distinct possibility of cyclone storms developing in the North Arabian Sea.

The word "cyclone" is of Greek origin and means a "coil of snake". No doubt, fully developed cyclones not only resemble the coil of a snake, they have a venom of thousands of snakes as far as their killing capability is concerned. These giants kill in three ways-by causing heavy to very-heavy continuous downpour leading to floods, strong to very-strong sustained winds, and tidal waves. The distinguishing property of the cyclonic storm is, however, the onslaught of tidal waves which often accompany the storms along with strong sustained winds and torrential rains.

Tropical cyclones are classified according o the maximum force of winds which accompany them as indicted in the following:

Depression : winds up to 33 knots.
Cyclonic storm : winds from 34 to 47 knots.
Severe tropical-cyclone storm : winds from 48 to 63 knots.
Hurricane : winds of 64 knots or more.

The major killing factor is, therefore, tidal wave assisted by very strong winds. As regards tidal waves, possible coincidence of the time of passage of an expected cyclonic storm with high and low tide times and lunar dates can appreciably add or decrease the actual heights of the tidal waves. This important factor is, therefore, is given due consideration when forecasting the passage of the cyclonic storms into the coastal areas.

It is worthwhile to evaluate how great is the danger of cyclonic storms striking Karachi or other coastal areas of Because of its very high population and industrial growth, Karachi merits special attention. Although nobody except Providence knows what fate awaits us, the changing natural processes and events do provide a clue to us. One of the parameters utilized by meteorologists is the climatology or past records of weather events.

In this connection, meteorological data about the cyclonic storms formed in the Arabian Sea during the last 100 years is given below:

• June 14-18, 1895: Cyclone made land fall along Balochistan Coast between Pasni and Gwadar after weakening into depression.
• April 26 - May 3, 1901: Severe cyclone weakened into a  depression before making a landfall near Jiwani.
• May 7-13, 1902: Severe cyclonic storm weakened into a cyclonic storm and made landfall along Sindh Coast near Keti Bunder.
• June 11-16, 1902: Severe cyclonic storm crossed the coast near Karachi.
• June 4-6, 1907: Severe cyclonic storm crossed the Sindh Coast near Karachi.
• June 18-20, 1907: Severe cyclonic storm made landfall south of Karachi.
• June 16-20, 1926: Cyclone struck Indian Gujrat, recurved again into Sea, intensified further and hit the Sindh Southeast of Karachi.

June 5-9, 1948: Severe cyclonic storm weakened into cyclonic storm before crossing the Mekran Coast near Jiwani.

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