The pictures are especially important to track hurricanes and other powerful storm systems.

Meteorologists use radar to track storms, hurricanes and tornadoes.

Mr. Lisman said he and city officials use the Internet to track hurricanes, which he said makes their ability to determine the potential threat easier and more accurate.

Bjorn Lambrigtsen, scientist who is part of a large effort to track hurricanes and understand what powers them.

In Canada, the Convair 580 is used by National Research Council to track hurricanes.

To the Editor: I moved to New York from New Orleans almost 25 years ago, but have continued to track hurricanes.

Army officials routinely track hurricanes, and had been following the storm for two weeks, since it began swirling off the west coast of Africa.

Students used NASA Web sites to track hurricanes, graph their intensity and videotape them via computer.

The satellite, whose expected five-year lifetime will expire in February, is the source of vital pictures used to track hurricanes and other storms.

"Helped you track hurricanes."