Hurricane Ivan was the ninth named storm and the fifth hurricane of the 1998 Atlantic hurricane season. Ivan developed into a tropical depression after it moved off the coast of Africa. It later became a tropical storm, then a hurricane, as it moved northwest, and then recurved to the northeast and out to sea. It came close to the Azores later on in its life, the first Azores strike on the Azores since 1992's Hurricane Bonnie.
Ivan caused no reported damage or fatalities.
|Formation||September 19, 1998|
|Dissipation||September 27, 1998|
|Highest winds||90 mph|
|Lowest pressure||975 mbar|
Ivan developed from a tropical wave that was easily identified over western Africa near Greenwich Meridian on September 14. The wave had a concentrated area of thunderstorms at this time. However, as it moved off the coast, convection decreased. Convection redeveloped within the wave on September 17 while it was located south of the Cape Verde Islands. The cloudiness became more concentrated near the axis of the wave on September 18, with Dvorak classifications being issued on the wave that day. It is estimated that the wave organized enough to become a tropical depression at 0000 UTC on September 19, while located about 175 nm southwest of the Cape Verde Islands. After forming, the depression moved northwest from September 20 to September 25. The system strengthened into Tropical Storm Ivan late on September 20. Because Ivan was embedded in an environment with troughs, its development was slow, due to strong vertical wind shear brought by the troughs.
Ivan reached 65 mph on September 22, and developed what could've been a possible eye for about an hour, before it disappeared. At 1400 UTC on September 23, the eye was reappeared and was more discernable than it was earlier, indicating that Ivan was becoming a hurricane as it neared 30°N. The eye disappeared once again, but then became more distinct with a diameter of about 20 nm, and Ivan is estimated to have reached its peak intensity of 90 mph as a hurricane on the morning of September 26. At this time, the pressure was 975 mb. At the time, Ivan was located 300 miles west of the Azores. At the time, the influence of upper-level troughs on Ivan were decreasing, and Ivan's track was increasingly controlled by westerlies to the north. Late on September 26, Ivan's eye disappeared again, for the final time. Ivan's inner core of convection rapidly deteriorated as Ivan moved eastward over cooler waters to the north of the Azores on September 27, becoming extratropical.
Ivan then became a weakening extratropical cyclone, then a gale, which moved northeastward.
Lack of Retirement
Because there was no damage, the name Ivan wasn't retired in the Spring of 1999 by the World Meteorological Organization. It was retired in 2004, however, and was replaced with Igor for the 2010 Atlantic hurricane season.