Tropical Storms and Hurricanes

Extremely strong tropical storms go by a number of different names, depending on
where they occur. Over the Atlantic and the eastern Pacific they are known as hurricanes.
Those over the extreme western Pacific are called typhoons; those over the
Indian Ocean and Australia are cyclones.

Hurricanes obtain most of their energy from the latent heat released by condensation and are most
common where a deep layer of warm water fuels them. August and September are the prime hurricane months
in the Northern Hemisphere, while January to March is the main season in the Southern Hemisphere.


The hurricane eye is a region of relatively clear skies, slowly descending air, and light winds.
Along the margin of the eye lies the eye wall, the zone of most intense storm activity with
the strongest winds, thickest cloud cover, and most intense precipitation of the entire hurricane.
























Hurricanes form only where the ocean has a deep
surface layer with temperatures above 27 °C (81 °F).
The need for warm water precludes hurricane formation
poleward of about 20 degrees because
sea surface temperatures are usually too low there.

Storm surge is a rise in water level induced by the hurricane.
Strong winds blowing toward a coast force surface waters
landward and thereby elevate sea level. Low atmospheric
pressure in a hurricane also contributes to the storm surge.
For every millibar of pressure decrease,
the water level rises 1 cm.