NASA's Aqua Satellite Tracking 2 Southern Hemisphere Systems for Tropical Development
Two tropical low pressure systems caught the infrared eye of NASA's Aqua satellite today and they're being watched for possible development into tropical cyclones. The low in the southwestern Pacific Ocean appears to be twice as wide as the system in the Southern Indian Ocean.
NASA's Aqua satellite circles the globe twice a day and captures a variety of images from several satellites that fly aboard. The Atmospheric Infrared Sounder (AIRS) instrument captured images of the tropical lows on April 13, 2011. System 92S is located in the Southern Indian Ocean about 340 miles west of Darwin, Australia. System 93P is in the Southwestern Pacific Ocean about 580 miles northwest of Noumea, New Caledonia.
System 93P in the southwestern Pacific Ocean stretches from 152 to168 East latitude (16 degrees) approximately 1040800 nautical miles (in longitude) wide. Its center was approximately near 15.2 South latitude and 159.5 East longitude. The width of the AIRS infrared data swath (the width of the false-colored imagery) extends about 1056 miles (1700 kilometers), and System 93P filled up about more than four-fifths of that swath, indicating that the low is very large.
The Joint Typhoon Warning Center (JTWC), the organization that forecasts tropical cyclones in both the Southern Indian Ocean and Southern Pacific Oceans noted that visible imagery of System 93P showed consolidation of convection within the storm. There is also curved banding of thunderstorms around the low-level center. Sea surface temperatures are warm enough to support a tropical cyclone (at least 80F/27C), however, the potential for development of System 93P remains poor over the next 24 hours.
System 92S is about half the size of System 93P. System 92S stretches from 123 to 131 East latitude (8 degrees) in the Southern Indian Ocean, which is approximately 400 520 nautical miles (in longitude) wide. The center of System 92S is near 12.0 South latitude and 125.0 East longitude.
This low appears to be more consolidated and organized than System 93P. System 92S has a larger more concentrated area of strong convection than System 93P, and that convection is located around the northern and western edges of the storm. Because System 93P is in an area of moderate vertical wind shear, the JTWC also gives this low a poor prognosis for development in the next 24 hours, but that could change.
Rob Gutro, NASA's Goddard Space Flight Center
, Greenbelt, Md.