Comparative Look at Megi as Tropical Depression and Typhoon16.4N 122.7E
These images offer a comparative look at the tropical storm system known as Megi (15W). The still images show the system as a tropical depression on October 13th, while the animated imagery shows the system at typhoon strength on October 18th. The following is the history of the storm’s development:
Late on October 12, the JMA reported that a tropical depression had formed to the west of Guam. During October 13, the JTWC designated the tropical depression as 15W. Later that day, the JMA and the JTWC reported that the depression had intensified into a tropical storm and named it as Megi.
On October 15, The JTWC reported that the storm had intensified into a category 2 typhoon, but the JMA were only monitoring the system as a Severe Tropical Storm.  Later that day, the JMA reported that the storm strengthened into a typhoon.
Early on October 16 the system entered the Phillipine Area of Responsibility and the PAGASA began to issue advisories on Megi, giving it the local designation of “Juan”. That same day, Megi continued to intensify and was upgraded by the JTWC to a category 3 typhoon.
Early on October 17, the JTWC reported that Megi had intensified into a category 5 super typhoon– the first super typhoon of the season and the first since Nida in November 2009. In the night of October 17, the intensity of Megi strengthened to 895 hPa (mbar), making Megi the strongest typhoon since Typhoon Yuri in 1991, and the first Pacific typhoon to reach lower than 900 hPa (mbar) in the 21st century and the first to do so anywhere in the world since Hurricane Wilma in the Atlantic in 2005.
It was also the first tropical cyclone in the 21st century to have one-minute sustained winds of 190-mph, and the first since Hurricane Allen in the Atlantic in 1980. In the morning of October 18, Megi continued to intensify to 885 hPa (mbar), making Megi the strongest typhoon since Typhoon Vanessa in 1984. It made landfall at that intensity, the most intense landfalling storm ever recorded anywhere in the world, surpassing the 1935 Labor Day hurricane.