2006 in review: the global tropical cyclone season

While no records were set in any ocean basin for number of tropical cyclones or number of intense tropical cyclones, 2006 saw a number of remarkable storms. Here's a summary of the most notable storms of the year, and the hardest hit countries:

Most intense tropical cyclone of 2006: Cyclone Monica.
Tropical Cyclone Monica, which made landfall on the sparsely populated northern coast of Australia in April, was the most intense tropical cyclone of 2006. The Joint Typhoon Warning Center estimated maximum sustained winds of 180 mph with gusts to 220 mph at 00 GMT April 24, and a minimum pressure of 879 mb. However, other satellite measurements of Monica's peak intensity were different--TCWC Darwin reported a minimum pressure of 905 mb at 5:00pm ACST (0730 UTC) on April 23, and an unofficial estimate from the University of Wisconsin put Monica's lowest pressure at 868.5 mb--1.5 mb lower than the world record low pressure observed in Super Typhoon Tip of 1979. Monica brought a 5-6 meter (16-20 foot) storm surge to the coast when it made landfall, and Margie Kieper's View From the Surface blog from yesterday has an impressive photo of the incredible damage Monica did to the forest on the Australian coast.

Monica was the most intense cyclone ever observed in the Southern Hemisphere, which is remarkable, given that she formed in the last half of April, when the Australian cyclone season is typically over. The co-record holder, also with a minimum pressure of 879 mb, is held by Cyclone Zoe of 2002, a Category 5 storm that affected several small islands in the Solomon chain. Reliable records of Southern Hemisphere cyclones only go back to the 1980s, so it is likely that there were other storms with lower pressures in the Southern Hemisphere during the past century. The lowest pressure measured at the surface in a Southern Hemisphere cyclone was 905 mb at North Rankin A gas platform during Cyclone Orson on 22-23 April 1989. Orson had 160 maximum sustained winds at the time, making it a Category 5 storm.


Figure 1. Eye of Tropical Cyclone Monica at 0430 GMT April 24 2006. Image credit: NASA.

Hardest hit country in 2006: the Philippines
The 2006 typhoon season saw an unprecedented five major (Category 3 or higher) typhoons make landfall in the Philippines, plus one Category 2 storm. Officially, 2049 people are listed as dead or missing and presumed dead from the 2006 typhoon season. Another 1122 died after monsoon rains triggered a landslide that buried the entire village of Guinsaugon in the central island of Leyte in February. In all, the six typhoons caused about $1.3 billion in damage--the most damaging typhoon season in Philippine history. For comparison, damage from all Philippine typhoons in the 20th century was $5.6 billion.


Figure 2. The fearsome sixsome of Philippine typhoons in 2006. From upper left to upper right: Super Typhoon Chanchu (May, Category 2 at landfall); Super Typhoon Xangsane (Category 4, September); Super Typhoon Cimaron (Category 5, October). From lower left to lower right: Typhoon Chebi (November, Category 3); Super Typhoon Durian (November, Category 4); Typhoon Utor (December, Category 3). A Super Typhoon is any storm with sustained 1-minute average winds of 150 mph or greater.

Deadliest tropical cyclone of 2006: Super Typhoon Durian
Super Typhoon Durian was the worst of the Philippine typhoons in 2006. Durian initially hit the island of Catanduanes as a Category 4 typhoon with sustained winds of 145 mph. Virtually every building on the island was damaged or destroyed, and Durian was judged the worst typhoon ever to hit the island. Next, Durian powered ashore into extreme southern Luzon Island in the province of Albay, still packing Category 4 winds of at least 135 mph. Durian passed directly over Mayon, the most active volcano in the Philippines and one of the country's most famous tourist attractions because of its near-perfect cone. Loose rock that the volcano had deposited in a July eruption rushed down the slopes in the form of deadly mudslides, thanks to Durian's torrential rains. Estimates from NASA's TRMM satellite of the rain amounts were 8-12 inches in a 24 hours period. The mudslides swept into villages and rivers at the foot of the Mayon Volcano. At least 1479 people died in the Philippines, mostly in mudslides near the Mayon volcano. This was the third deadliest typhoon in Philippine history, and the most damaging. Durian destroyed 211,000 homes, and damaged another 308,000. Durian weakened to a Category 1 typhoon after it emerged in the South China Sea, and passed along the coast of southern Vietnam. Durian killed 95 more people in Vietnam, destroying 50,000 homes and damaging 195,000. Damage was estimated at $456 million in Vietnam.

Most damaging tropical cyclone of 2006: Cyclone Larry
Australia got hit exceptionally hard by tropical cyclones in 2006, suffering hits by three major cyclones--Category 5 Monica in April, Category 3 Glenda in March, and the worst blow, Cyclone Larry on March 20, 2006. Cyclone Larry was a borderline Category 3/4 storm on the U.S. Saffir/Simpson scale, and struck Queensland with a fury unmatched in that region in perhaps a century. Damage from the storm was estimated at over $1 billion U.S. dollars.


Figure 3. Cyclone Larry. Image credit: NASA.

Longest duration intense tropical cyclone in history: Ioke
Hurricane Ioke (a.k.a. Super Typhoon Ioke after it crossed the Date Line) was the strongest hurricane ever recorded in the Central Pacific, and remained at Category 4 or 5 strength longer than any tropical cyclone on record. Ioke spent 36 (33 consecutive) 6-hourly reports at that strength. The previous records were held by 2004's Hurricane Ivan with 33 (32 consecutive) and 1997's Typhoon Paka with 27 (25 consecutive) 6-hourly reports. The Accumulated Cyclone Energy (ACE) for this one storm was about 81--higher than the ACE index of 79 accumulated by all the tropical cyclones in the Atlantic 2006 hurricane season.


Figure 4. Super Typhoon Ioke. Image credit: NASA.

Jeff Masters