Typhoon Megi (2016)

Typhoon Megi (Helen)

Typhoon (JMA scale)
Category 4 (Saffir–Simpson scale)
Typhoon Megi making landfall in Taiwan at peak intensity on September 27
Formed	September 22, 2016
Dissipated	September 29, 2016
Highest winds	10-minute sustained: 155 km/h (100 mph) 1-minute sustained: 220 km/h (140 mph)
Lowest pressure	945 hPa (mbar); 27.91 inHg
Fatalities	24 dead, 17 missing
Damage	$944.7 million (2016 USD)
Areas affected	Caroline Islands, Ryukyu Islands, Taiwan, China (including South and East)
Part of the 2016 Pacific typhoon season

Typhoon Megi (pronounced [me̞.ɟi]), known in the Philippines as Typhoon Helen, was a large and powerful tropical cyclone which affected Taiwan and China in late September 2016. It is the seventeenth named storm and the seventh typhoon of the annual typhoon season.

A tropical disturbance formed northeast of Pohnpei on September 19. Two days later, the Japan Meteorological Agency (JMA) upgraded the low-pressure area to a tropical depression early on September 21, and the Joint Typhoon Warning Center (JTWC) also issued a Tropical Cyclone Formation Alert shortly after that; however, the low-level circulation center (LLCC) of that disorganized system was exposed with fragmented convection. The JMA upgraded the system to a tropical storm and named it Megi early on September 23, when the JTWC also indicated that the monsoonal circulation had consolidated, resulting in upgrading it to a tropical depression but lacking of a definitive center. Six hours later, the JTWC upgraded Megi to a tropical storm. When formative banding and cloud tops were improving and cooling late on the same day, the JMA further upgraded the broad system to a severe tropical storm.

Tracking along the southwestern periphery of the deep-layered subtropical ridge on September 24, Megi was trying to form an eye that prompted both of the JMA and then the JTWC upgrading it to a typhoon. It also received the name Helen from PAGASA as the system entered the Philippine Area of Responsibility on the same day. However, despite being under excellent environmental conditions, Megi stopped intensifying further since September 25. Located in an area of low vertical wind shear and above warm sea surface temperatures near 30ºC, diurnal weakening of convection still continued to occur, especially over the northern half of the system. With excellent radial outflow tapping into westerlies and a large tropical upper tropospheric trough (TUTT) cell to the east, a defined eye remained absent from the typhoon. After completing an eyewall replacement cycle on September 26, Megi eventually started to strengthen more in the afternoon, resulting in a ragged but larger eye embedded in this large typhoon. The JMA indicated that Megi had reached its peak intensity at 18:00 UTC, with ten-minute maximum sustained winds at 155 km/h (100 mph) and the central pressure at 940 hPa (27.76 inHg).