It took the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite a full five minutes to fly over this expansive cloud pattern on April 29, 2009. The sprawling "S"-shaped swirl is actually two cyclones that seem to be feeding on each other. Polar cyclones often form as a result of low-pressure systems over the ocean, and usually bring winds and heavy snow.
MODIS acquired this photo-like image over the cold waters of the South Atlantic Ocean, where winter is approaching.
Credit: Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC Click to enlarge. (2.7 mb)
Welcome to JetStream, the National Weather Service Online Weather School. This site is designed to help educators, emergency managers, or anyone interested in learning about weather and weather safety.
The information contained in JetStream is arranged by subject; beginning with global and large scale weather patterns followed by lessons on air masses, wind patterns, cloud formations, thunderstorms, lightning, hail, damaging winds, tornados, tropical storms, cyclones and flooding. Interspersed in JetStream are "Learning Lessons" which can be used to enhance the educational experience.
You are free to use the materials in any manner you wish. We welcome your feedback on this project. Your input will greatly assist others in teaching the "hows" and "whys" of weather. Not sure where to begin? Click to see all topics in JetStream in the Topic Matrix. Contact Us:
Steven Cooper Steven.Cooper@noaa.gov
Deputy Regional Director, NWS Southern Region Headquarters, Fort Worth, Texas
Michael Vescio Michael.Vescio@noaa.gov
Meteorologist-in-Charge, NWS Pendelton, Oregon
Dennis Cain Dennis.Cain@noaa.gov
a.k.a. "Professor Weather", NWS Fort Worth, Texas