Typhoon Songda was east of the Philippines when the Tropical Rainfall Measuring Mission (TRMM) satellite had an early evening view on May 25, 2011 at 0903 UTC (05:03 EDT) and saw good organization within the storm and heavy rainfall. Songda has intensified into a major typhoon as it tracks parallel to the east coast of the northern Philippines, spawning warnings.

Both TRMM’s Microwave Imager (TMI) and Precipitation Radar (PR) instruments were used to provide the rainfall analysis. TRMM’s TMI had the best coverage of rainfall with Songda and showed well organized bands of moderate to heavy rainfall converging into the typhoon. TRMM is managed by both NASA and the Japanese Space Agency, JAXA.

Infrared imagery from the Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua satellite showed an eye about 12 nautical miles wide and strong convection surrounding the eye on all sides. Songda intensified over the over the last 12 hours because of very warm sea surface temperatures between 30 and 31 Celsius, and low wind shear.

At 1500 UTC (11 a.m. EDT) on May 25, Songda’s maximum sustained winds were near 105 knots (120 mph/194 kmh) making it a Category Three Typhoon on the Saffir-Simpson scale. Sondga was located about 385 nautical miles east-southeast of Manila, Philippines and is now moving northwestward near 5 knots (6 mph/9 kmh). Yesterday it was moving to the west-northwest, so the curving northward has already begun.

Songda is predicted to become a very powerful category 4 super typhoon with wind speeds peaking at 125 knots (143 mph/231 kmh) as it passes to the northeast of the Philippines. By Friday, the current forecast track takes Songda’s center very close to the island with Kadena Air Base in the Northwestern Pacific Ocean.

Bune is now an extra-tropical cyclone in the Southern Pacific Ocean far to the northeast of northern New Zealand. NASA infrared data is showing weaker thunderstorms and waning convection, indicating that Bune is on its way into history. According to the New Zealand Meteorological Service, extra-tropical Cyclone Bune is expected to stay to the northeast of Gisborne on March 30 and will then move away toward the southeast on March 31. Rains that are forecast for Gisborne on March 30 will be from southerly wind flow and not associated with extra-tropical cyclone Bune.

NASA’s Aqua satellite flew over Bune on Sunday, March 27 when it was still a weak category one cyclone with maximum sustained winds near 74 mph (119 kmh/64 knots). The image still showed that Bune had an eye at that time. Animated satellite infrared imagery today, March 29, taken from the Atmospheric Infrared Sounder (AIRS) instrument that also flies aboard the Aqua satellite showed that the cloud tops of the thunderstorms were warming quickly and convection was dissipating. Warming cloud tops indicate that the thunderstorms are falling in height, and the lower the thunderstorms, the less powerful the uplift behind them is, and the weaker they are.