Typhoon Tip, which formed in the Western Pacific in October 1979, holds the distinction of being the largest tropical cyclone ever recorded on Earth. This massive system was historically significant for both its physical expanse and its record-setting intensity. The storm’s size and power led to extensive study, including approximately 60 reconnaissance missions flown by the U.S. Air Force, making it one of the most closely observed cyclones in history.
Defining the Record-Breaking Scale
The immense size of Typhoon Tip is what truly set it apart, with its wind field reaching a maximum diameter of 1,380 miles (2,220 kilometers) at its peak. This physical expanse is nearly double the diameter of the previous largest recorded storm, Typhoon Marge in 1951. To grasp this size, the storm’s circulation was comparable to nearly half the size of the contiguous United States, or the distance from New York City to Dallas, Texas.
Meteorologists measure a tropical cyclone’s size by tracking the distance from the center to the extent of its gale-force winds (sustained winds of 39 mph or 63 km/h or greater). This measurement is often determined by the furthest closed isobar, a line connecting points of equal atmospheric pressure. When Tip reached its maximum size, its gale-force winds extended 675 miles (1,086 kilometers) from the center of circulation.
Meteorological Intensity and Power
Typhoon Tip was also one of the most powerful storms ever measured, combining immense scale with extreme intensity. On October 12, 1979, the storm reached its peak strength, recording a worldwide record-low sea-level pressure of 870 hPa (millibars). This pressure reading is the lowest ever officially measured at sea level globally.
The storm’s central pressure measurement is a key indicator of its power, as lower pressure correlates with a stronger pressure gradient that fuels higher wind speeds. At this peak intensity, Tip’s maximum sustained winds were estimated at 190 mph (305 km/h), which is the upper limit of a Category 5-equivalent Super Typhoon on the Saffir-Simpson Hurricane Wind Scale. For context, the eye of the storm, the relatively calm center, was only about 9.3 miles (15 kilometers) wide at this time, a stark contrast to the colossal size of its overall wind field.
Trajectory and Historical Context
Typhoon Tip originated from a disturbance within the monsoon trough near Pohnpei in Micronesia on October 4, 1979. Its early development was slow and erratic due to the presence of Tropical Storm Roger, which hindered its organization. As Roger moved farther north, Tip encountered highly favorable environmental conditions in the Western Pacific, allowing for rapid growth.
The massive expansion was primarily attributed to extremely low wind shear and warm sea surface temperatures, which provided the engine for the storm to rapidly intensify. After passing near Guam, Tip quickly developed into a Super Typhoon, reaching its peak size and intensity in the open ocean west-northwest of Guam. The storm maintained a west-northwestward track before eventually curving toward the northeast, influenced by an approaching trough.
Final Impact and Legacy
The colossal typhoon gradually weakened as it tracked toward the northeast, eventually making landfall on the Japanese island of Honshū on October 19. Although diminished, its sheer size still delivered widespread destruction across the region. The storm caused extensive flooding, over 600 mudslides, and damaged or destroyed thousands of homes in Japan.
A notable incident occurred at the U.S. Marine Corps Camp Fuji, where heavy rainfall and strong winds breached a flood-retaining wall near a fuel farm. The resulting erosion caused fuel storage bladders to rupture, and the spilled gasoline flowed into nearby huts where Marines were sheltering. A heater then ignited the fuel, causing a fire that tragically killed 13 U.S. Marines and injured 68 others.
Typhoon Tip remains a benchmark storm, offering meteorologists valuable data for understanding the upper limits of tropical cyclone development and the complex atmospheric dynamics that govern such massive weather systems.