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Hurricane Season 2007: Hagibis (Western Pacific)
Typhoons Mitag and Hagibis

Two tropical cyclones, Hagibis and Mitag, dumped heavy rain on the Philippines between November 19 and November 29, 2007. Known in the Philippines as “Lando” and “Mina,” respectively, the two storms caused at least 29 deaths as a result of flooding and mudslides, reported the Agence France-Presse (AFP) news service on November 29. Hagibis struck the island nation first, passing through the central part of the islands on November 19. The storm then tracked west over the South China Sea towards Vietnam before making a dramatic “U-turn” back towards the Philippines. The second storm, Mitag, made landfall as a Category 1 storm on Luzon on November 25 and November 26 before turning out to sea.

Satellite data on storms Mitag and Hagibis
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This image shows the rainfall the two storms brought to the Philippines and the surrounding ocean between November 19 and November 29, 2007. The image was made from the near-real time, Multi-satellite Precipitation Analysis (MPA) at NASA Goddard Space Flight Center. Two separate areas of heavy rain, concentric circles of red and orange, lie off the coast of Vietnam over the South China Sea and along the eastern edge of the Philippines in the Philippine Sea. These two areas are associated with Hagibis and Mitag, respectively. The storm tracks are shown by the thin black lines with the positions recorded at 00:00 UTC each day marked with storm symbols.

The highest rainfall totals associated with Hagibis occurred over the South China Sea where the storm made its U-turn. The highest rainfall totals, shown in this image as dark red, exceed 500 millimeters (20 inches). The heaviest rain left by Typhoon Mitag occurs along either side of the storm’s path as it approached the Philippines. The image reveals that some of this heavy rain impacted the far eastern islands of the central Philippines. The northern island of Luzon, where Mitag made landfall, received on the order of 100 to 200 mm (4 to 8 inches) of rain (shown in green).

The image shows that the heaviest rain fell over the ocean, and this rain, along with high winds and waves, damaged or destroyed fishing vessels. As of November 29, 26 fishermen were still missing from a Filipino fishing vessel that capsized in the South China Sea as Hagibus passed overhead, reported the AFP. Two Chinese fishing vessels also sank in the area with 12 crew missing.

The Multi-satellite Precipitation Analysis is based in part on data collected by the Tropical Rainfall Measuring Mission (TRMM) satellite, which came into service in November 1997 with the primary mission of measuring rainfall in the tropics using a combination of passive microwave and active radar sensors. TRMM is a joint mission between NASA and the Japanese space agency, JAXA.

Steve Lang
Image credit: Hal Pierce (SSAI/NASA GSFC)

Two Cyclones Hit Philippines

Two tropical cyclones recently struck the Philippines within a week's time. On Nov. 19, 2007, then Tropical Storm Hagibis passed through the central Philippines in the direction of Vietnam, leaving behind 13 dead. A week later Typhoon Mitag hit northern Luzon where it was responsible for 17 fatalities. This recent surge in tropical cyclone activity in the West Pacific may be related to an active Madden-Julian Oscillation (or MJO). The MJO is a large, slow-moving area of enhanced tropical convective (i.e., thunderstorm) activity that propagates eastward from the Indian Ocean into the Pacific. It has been linked to modulations in tropical cyclone formation.

Visualization of storms Hagibis and Mitag
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This image from TRMM the Tropical Rainfall Measuring Mission satellite (commonly known as TRMM) shows Tropical Storm Hagibis (lower left corner, center denoted by the tropical storm symbol) and Typhoon Mitag (upper right corner) both in the same overpass. The image was taken at 23:00 UTC (6:00 pm EST) 25 November 2007. It shows the horizontal distribution of rain intensity (top down view) within the two cyclones as viewed by TRMM. Rain rates in the center of the swath are from the TRMM Precipitation Radar (PR), a unique space-borne precipitation radar, while those in the outer swath are from the TRMM Microwave Imager (TMI). These rain rates are overlaid on infrared (IR) data from the TRMM Visible Infrared Scanner (VIRS). At the time of this image, Hagibis was in its weakening stages and just barely a tropical storm with sustained winds estimated at just 35 knots (40 mph) by the Joint Typhoon Warning Center. The center of circulation (denoted by the storm symbol) is completely devoid of rain. Mitag, meanwhile, is a Category 1 typhoon with sustained winds of 75 knots (86 mph). It too is weakening after having made landfall about 6 hours earlier. A broad band of moderate (green areas) intensity rain is seen spiraling into the center with embedded areas of heavy rain (red areas). With the storm's circulation having been disrupted by the terrain, the eye is hard to discern.

After re-emerging back over open water over the Luzon Strait north of Luzon, Mitag is now following a northeast track away from major land areas and is expected to continue weakening. Hagibis, however, which as one point was headed straight for Vietnam after passing through the Philippines, made a U-turn and is now on its way back to the Philippines. Fortunately, the system has already been down-graded to a tropical depression and is expected to continue weakening, but it still poses a threat for flooding. Efforts are still underway to locate crewman from a fishing vessel as well as a search aircraft near the Spratly Islands located in the South China Sea between the Philippines and Vietnam.

TRMM is a joint mission between NASA and the Japanese space agency JAXA.

Steve Lang
Image credit: Hal Pierce (SSAI/NASA GSFC)

A Sea of Tropical Activity: Western Pacific Has Three Tropical Cyclones

While the Atlantic Ocean hurricane season is winding down and ending officially on Nov. 30, the Tropical Cyclone season in the Western Pacific Ocean is in full swing. On Nov. 26, there are two tropical cyclones in the South China Sea: Mitag and Hagibis, and Tropical Depression 25W located far south of Japan.

Tropical Cyclone Mitag, also named 'Mina' in the Philippines and numbered 24W for the 24th storm of the season in the western Pacific is now centered in Luzon, the Philippines (to the right of this image). Tropical Cyclone Hagibis, also known as "Lando," and numbered 23W for the season's 23rd storm, is on its way to Manila. Tropical Depression 25W is not pictured in this satellite image from Nov. 25.

The Joint Typhoon Warning Center noted the location of Mitag on Nov. 26 at 12:00 UTC (7:00 a.m. EST) near 20.3 degrees north latitude and 120.6 degrees east longitude, approximately 140 nautical miles south of Kaohsiung, Taiwan. Mitag was moving north at 10 knots (11 mph), and had sustained winds of 65 knots (75 mph) with higher gusts. Mitag is a Category 1 hurricane.

Meanwhile, Tropical Depression Hagibis was located near 11.9 degrees north latitude and 116.8 degrees east longitude, or approximately 290 nautical miles southwest of Manila, Philippines. Hagibis has turned round and is heading back east across the South China Sea towards the Philippines. It has been tracking east- northeastward at 13 knots. Maximum sustained winds were near 30 knots (34 mph) with higher gusts.

Tropical depression 25W (no name) has tracked west-northwestward and intensified slightly on Nov. 26 at 15:00 UTC (10:00 a.m. EST). It is forecast to become extratropical by Nov. 28. On Nov. 26, Tropical depression 25W was located approximately 635 nautical miles south-southeast of Naha, Okinawa, Japan.

Satellite image of storms in Western Pacific
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This infrared image from 17:59 UTC (12:59 p.m. EST) Nov. 25 was created by data from the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite.

Each storm's clouds and rains are the blue and purple areas. This AIRS image shows the temperature of the cloud tops or the surface of the Earth in cloud-free regions. The lowest temperatures (in purple) are associated with high, cold cloud tops that make up the tops of Mitag and Hagibis. The infrared signal does not penetrate through clouds. Where there are no clouds the AIRS instrument reads the infrared signal from the surface of the Earth, revealing warmer temperatures (red).

Rob Gutro / Ed Olsen
Goddard Space Flight Center / Jet Propulsion Laboratory
Image credit: NASA/JPL