Cyclone George intensified into a powerful Category 4 Cyclone with wind gusts of up to 275 kph (171 mph) according to the Bureau of Meteorology's Tropical Cyclone Warning Center just as it was approaching the coastline of Western Australia. The storm made landfall east of Port Hedland on Thursday night (local time) the 8th of March 2007.

George formed into a tropical storm on the evening (local time) of March 3rd from an area of low pressure that moved off the coast of northern Australia and into the Timor Sea. As the storm headed due west, the center briefly crossed the Australian coastline on the 4th of March before re-emerging over open water on the 5th into the eastern Indian Ocean.

The Tropical Rainfall Measuring Mission (TRMM) satellite was placed into its low-earth orbit in November of 1997. Armed with both passive and active sensors, including the first space-borne precipitation radar, its primary mission is to measure rainfall from space; however, it also serves as a valuable platform for monitoring tropical cyclones over the global Tropics, especially over remote parts of the open ocean. This first image from TRMM shows George just as the storm was re-emerging off of the coast and into the Indian Ocean. The image was taken at 01:03 UTC (10:03 am Australian WDT) on 5 March 2007. The image shows the horizontal distribution of rain intensity within the system. Rain rates in the center swath are from the TRMM Precipitation Radar (PR), and 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 reveals a system that is still in the early stages of its development. Because the center had been over land, the system has not been able to develop. There is no eye and banding features (curvature) are weak as the circulation has not yet matured. However, significant areas of intense rain (dark red areas) are evident near the center and show where heat is being released into the storm, providing fuel for the circulation.

George continued to move due west on the 6th, taking it farther away from land. The system maintained tropical storm intensity. On the 7th, George strengthened into a Category 2 cyclone (roughly equivalent to a Category 1 hurricane on the Saffir-Simpson scale) before being drawn southward by a trough of low pressure. This next image was taken at 09:03 UTC (6:03 pm Australian WDT) March 7th just as George was strengthening and beginning to turn south. Although the center of the storm does not fall within the PR swath in this image, it is clear from the closed eye (green and blue ring with the open center) and the improved banding in the outer rain bands (dark red and bright green arcs denoting heavy to moderate rain intensities respectively) that George's circulation is now much better developed.

George continued to track due south towards the northern coastline of Western Australia on the 8th and began to intensify as well. This final image from TRMM was taken at 08:07 UTC (5:07 pm Australian WDT) March 8th as George was nearing the coast. Again, despite the center not being in the center of the swath, it is apparent that George is a strong storm, having a well-defined eye surrounded by a symmetric eyewall of moderate intensity rain (green ring). At the time of this image, George was rated as a Category 3 Cyclone by the Bureau's Tropical Cyclone Warning Center and would reach Category 4 soon after before it made landfall.



TRMM is a joint mission between NASA and the Japanese space agency JAXA. Images produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC).