TRMM

November 14, 2004 1611 UTC	November 16, 2004 0606 UTC
		RAINFALL ACCUMUMLATION AND TYPHOON POSITIONS

<-- --> <-- See LARGE [ 2.3 mb] QUICKTIME ANIMATION November 13-18, 2004 Rain Accumulation --> <-- --> <-- See SMALLER [.4 mb] QUICKTIME ANIMATION --> <-- --> <-- See MEDIUM [.9 mb] MPEG ANIMATION -->

TYPHOON MUIFA BRINGS HEAVY RAINS TO PHILIPPINES

Typhoon Muifa (known as Unding in the Philippines) continues to bring torrential rains to the Philippines as the slow-moving storm passes through the north central part of the islands. The Tropical Rainfall Measuring Mission (TRMM) satellite with its array of passive and active sensors has been monitoring the progress of Muifa, providing valuable information on its location, structure and intensity to forecasters. Muifa first became a tropical depression back on the 11th of November 2004 south of the Caroline Islands in the West Pacific. The storm moved steadily northwest passing well north of Palau and just south of the Yap Islands before entering the Philippine Sea. Muifa slowly organized into a tropical storm on the 14th. The first TRMM image shows Muifa at 16:11 UTC on the 14th of November as it neared the central Philippines. The image shows the horizontal distribution of rain intensity as seen from above by the TRMM satellite. Rain rates in the center swath are from the TRMM Precipitation Radar (PR), the first precipitation radar in space, while rain rates in the outer swath are from the TRMM Microwave Imager (TMI). The rain rates are overlaid on infrared (IR) data from the TRMM Visible Infrared Scanner (VIRS). TRMM shows that Muifa is not very well organized having no eye, a very asymmetric structure, and only weak banding evident in the moderate intensity rain field (green arcs). However, at this time, there are several areas of heavy rain with rates on the order of 2 inches per hour (dark red areas) in a large rainband north of the center.

The next TRMM image shows Muifa two days later at 06:06 UTC on the 16th. Muifa was still a tropical storm with maximum sustained winds estimated at 45 knots (52 mph) by the Joint Typhoon Warning Center. The large rainband that was north of the center is no longer present. Instead, most of the rain is west of the center, and only localized areas of heavy rain (red areas) are present. Muifa still does not have an eye though the moderate rain immediately west of the center does show some banding (green arc). Muifa now finally began to intensify becoming a typhoon on the 17th and a major typhoon on the 18th with maximum sustained winds approaching 115 knots (132 mph). Fortunately the center remained offshore. However, the storm stalled just off the east coast of the northern and central islands of the Philippines. This led to very heavy rainfall over parts of the islands.

The TRMM-based, near-real time Multi-satellite Precipitation Analysis (MPA) at the NASA Goddard Space Flight Center monitors rainfall over the global tropics. The last image shows MPA rainfall totals for the period 13-18 November 2004 associated with the passage of Muifa. It reveals an area of extreme rainfall on the order of 40 inches centered just east of the southern half of the main island of Luzon (dark red area). Most of southern Luzon and parts of the central Philippines received upwards of 10 to 20 inches of rainfall (green and yellow areas), while the island of Catanduanes and extreme southeastern Luzon may have been inundated by as much as 35 inches of rain (red to dark red areas). Storm symbols mark the 00Z positions beginning on the 15th. So far, 3 persons have been reported to have drowned as a result of Muifa. The storm is expected to continue crossing Luzon and move west into the South China Sea.