Rainfall Map of Mirinae’s Flooding Rains

Typhoon Mirinae drenched the Philippines and Vietnam over the last two weeks. Typhoon Mirinae dropped heavy rain over the central Philippines after hitting as a category two typhoon with wind speeds of 85 knots (~98 mph). Mirinae weakened to a tropical storm as it moved into the South China Sea but briefly increased to typhoon strength just before hitting Vietnam on Monday, November 2 in the southern coastal province of Phu Yen.

The Tropical Rainfall Measuring Mission (TRMM) satellite is managed by NASA and the Japanese Space Agency, JAXA. From its vantage point in space, TRMM flew over Typhoon Mirinae during its lifetime and catalogued its rainfall.

TRMM-based, near-real time Multi-satellite Precipitation Analysis (TMPA) at the NASA Goddard Space Flight Center, Greenbelt, Md. was used to monitor rainfall with Mirinae. Rainfall totals were calculated for the period from October 26 to November 2, 2009. Tropical storm, typhoon and tropical depression symbols were overlaid to show the locations of Mirinae from when it came ashore in the eastern Philippines until being downgraded to a tropical depression over Vietnam.

The TRMM rainfall analysis indicated that Mirinae dropped heavy rainfall with totals over 200 mm (~7.8 inches) in an area southeast of Manila in the Philippines. Typhoon Mirinae dropped heavy rainfall over a much larger area of Vietnam with a small area having rainfall totals over 275 mm (~10.8 inches). As with typhoon Ketsana in late September, Mirinae pulled moist air from the South China Sea and forced it up over terrain causing the heaviest rainfall to occur north of the typhoon.

Typhoon Ketsana took a similar path to Mirinae when it caused disasters in the Philippines and Vietnam in late September 2009. Tropical storm Ketsana took a more northern track, also making a final landfall in Vietnam.

Tropical Depression 97W Passing Through Central Philippines

Tropical Depression 97W hasn’t grown into a tropical storm and is now tracking through the central Philippines, far south of Manila. The storm is weakening and is dissipating, and NASA’s Aqua satellite verified that the thunderstorm cloud tops are not as cold as they were yesterday, indicating a weakening storm.

At 11 a.m. local (Asia/Manila) time on November 3, TD97W had maximum sustained winds near 30 knots (34 mph) and higher gusts. It was located 160 miles east of Manila, near 14.1 North and 123.7 East. The storm is kicking up 12-foot high waves.

NASA’s Aqua satellite flew over 97W at 1:30 a.m. local Asia/Manila Time this morning, November 3. An infrared image from the Atmospheric Infrared Sounder (AIRS) instrument revealed warmer thunderstorm cloud tops, little or no convection (rapidly rising air that forms thunderstorms, and powers tropical cyclones).

Tropical Depression 97W (TD97W), named “Tino” in the Philippines, is forecast to move on a south-southwesterly track, over Tabaco City, Ligao, Oas, and Naga City into the Ragay Gulf. It will continue moving south-southwest through the Sibuyan Sea and into the Mindoro Strait, while bringing rains to areas that include the cities of Kalibo, Roxas City and San Jose de Buenavista.

The U.S. Navy’s Joint Typhoon Warning Center (JTWC), the organization that forecasts tropical cyclones in that part of the world, noted in their discussion this morning, “Animated multi-spectral imagery shows an increasingly exposed low level circulation center (LLCC) with very little to no central convection. Over the past 12 hours, the deep convection has waned and the LLCC has steadily tracked southward with the low- to mid-level northeasterly flow associated with the cold surge coming off the Asian land mass.”