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View Full Version : MODIS: Cyclones Olaf and Nancy in the South Pacific


tlr online
18-02-05, 03:11
The Aqua MODIS instrument captured this true-color image of Tropical Cyclones Olaf and Nancy approaching each other in the South Pacific Ocean on February 16 at 1:10 UTC. At the time this image was taken, both cyclones were packing winds of up to 135 knots (155 mph) and were buffeting the outlying islands of Samoa, American Samoa and the Cook islands, but had so far caused little damage and no injuries.

It is very unusual for cyclones to be so close together in the South Pacific, and it’s hard to predict how the storms will interact. One possibility is that the weaker storm will be tugged off course by the large-scale atmospheric circulation of the other. Eventually the weaker storm will seem to “orbit” the stronger storm. The second possibility is that the outflow from one storm will impede the outflow from the other storm, weakening the second storm. Regardless of the interaction, the storms pose a potentially deadly threat to American Samoa and the Cook Islands.

The centre of cyclone Olaf was about 150 kilometers (93 miles) northwest of Samoa's main island of Savai'i and was moving at 15 km an hour. The centre of cyclone Nancy, a category 3 storm, had already passed over the southern Cook Island atolls of Aitutaki and Mitiaro and was about 100 kilometers (62 miles) northeast of the main island of Rarotonga.

http://modis.gsfc.nasa.gov/gallery/images/image02172005_md.jpg

Copyright 2005 NASA