First noted southeast of Guam on July 31, development of this system was initially slow to occur; it was first classified on August 5, and was upgraded into a tropical storm the next day.

Abby finally weakened back into a tropical storm on August 17 not long after making landfall in Japan.

Typhoon Abby also brought several consecutive days of rain to southern and central Japan, resulting in widespread damage.

While moving south of Guam, the area failed to organized significantly until August 3, when thunderstorm activity increased in coverage.

However, a Hurricane Hunter aircraft investigated the system early on August 5 and was able to locate a closed surface circulation.

Based on this, both the Joint Typhoon Warning Center (JTWC)[1] and the Japan Meteorological Agency (JMA) upgraded the system into a tropical depression.

[1] At 1800 UTC on August 6, both the JMA and the JTWC upgraded Abby to typhoon status when an eye began to form within the central dense overcast, a large mass of deep convection.

Twelve hours later, the JTWC estimated maximum winds of 245 km/h (150 mph), making Abby a super typhoon.

[2] After maintaining peak intensity for several hours, Abby began to weaken as its forward speed slowed.

However, this trend was short lived[2] and Abby steadily weakened as it made the long anticipated turn to the northeast in the general direction of Japan.

[1] On August 12, two tropical cyclones developed in the South China Sea, but due to the massive size of Abby, this had little effect on the typhoon.

Shortly thereafter, Abby moved ashore Hamamatsu and began to turn northeast, encountering rugged terrain near Tokyo.

A swimmer drowned in the lake on the western tip of Honshu;[21] a fisherman was swept away by high waves off Kamogawa.

[24] Major railway lines halted operations throughout central Japan while many other trains arrived late,[25] leaving 18,000 individuals stranded.