Nature is full of circles and among the most dramatic are the immense cyclonic storms spawned in the Atlantic (hurricanes), Pacific (typhoons) and Indian Ocean (cyclones). Not only are the storms circular, in the center is a most unusual natural phenomenon – the eye. Some storms have ill defined eyes and the eye of a given storm can organize and collapse and then reappear as the storm varies in intensity. When well defined as a circle, the eye of storm is relatively calm and clear and has the lowest sea level barometric pressures ever recorded. (Typhoon Tip in 1979 set the record for lowest barometric pressure in at sea level at 25.69 inches of mercury compared to average sea level pressure of 29.92. It was also the largest storm with a diameter of 1,380 miles of hurricane force winds at one point.)
In 1999, Hurricane Floyd became one of the largest storms ever to threaten the USA. The headquarters of the National Geographic Society in Washington DC has a really neat huge three dimensional relief map of Floyd made from satellite digital photo data where you can see the eye clearly defined. On September 14, 1999, Floyd struck the Bahamas at Category 4 (5 being highest) force with sustained winds of 155 mph. It later weakened and headed up the East Coast of the US where its heavy rains reached New York City, closing the schools on September 16, 1999.
The bad news is that you are on the Bahamas and Floyd is raging by. The good news is that you are safe in the upper story of a hotel built to withstand Floyd’s winds. After the fiercest winds imaginable, all of sudden it gets calm. You are in the eye. You hear on your battery powered radio that the eye is 50 miles in circumference and that the storm is drifting along at 13mph. Approximately how soon with the eye pass you and the fierce winds resume?
Bonus question: What was the circumference of Typhoon Tip when it was recorded as the largest storm on record?
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