NASA TRMM Satellite captures Tropical Storm Phanfone fragments

On Sept. 30, the TRMM satellite passed over Tropical Storm Phanfone and saw fragmented bands of thunderstorms with some isolated areas of heavy rain (red) falling at 2 inches per hour. 

Credit: NASA/SSAI, Hal Pierce

The bands of thunderstorms wrapping around Tropical Storm Phanfone in the Northwestern Pacific Ocean appeared fragmented to NASA's TRMM satellite.

On Sept. 30, a typhoon watch remains in effect for the far northern Marianas Islands including Pagan and, extinct volcano, Alamagan.

Tropical storm warnings have been cancelled for Tinian and Saipan, but remain in effect for Pagan, Alamagan and surrounding waters.

A flash flood watch remains in effect for the island of Saipan. For updated forecasts for these islands, visit the U.S. National Weather Service Office's Guam website.

On Sept. 30 at 01:51 UTC (Sept. 29 at 9:51 p.m. EDT) from its orbit in space, NASA and the Japan Aerospace Exploration Agency's Tropical Rainfall Measuring Mission (TRMM) satellite passed over Tropical Storm Phanfone.

Most of the rainfall in the fragmented bands of thunderstorms was light to moderate, falling at a rate between 10 and 20 mm (0.39 to 0.79 inch) per hour.

However, TRMM saw some isolated areas of heavy rain falling at 50 mm (2 inches) per hour.

The Joint Typhoon Warning Center noted that animated multi-spectral satellite imagery on Sept. 30 revealed that the tropical storm had slightly unraveled as the bands of thunderstorms had become even more fragmented than they were on Sept. 29.

On Sept. 30 at 1500 UTC (11 a.m. EDT) Phanfone's maximum sustained winds were near 45 knots (83.3 mph/51.7 kph).

It was centered near 17.1 north latitude and 145.0 east longitude, about 103 nautical miles north of Saipan. Phanfone was moving to the west-northwest at 15 knots (17.2 mph/17.7 kph).

Phanfone is forecast to intensify as it moves in a generally northwesterly direction through warm sea surface temperatures, toward the island of Iwo To.

Forecasters at the Joint Typhoon Warning Center expect Phanfone to reach typhoon strength on Oct. 1 and maintain it as it passes west of the island of Iwo To on Oct. 3, later moving toward Japan.