AIRS Image of Helen (IMAGE) NASA/Goddard Space Flight Center Caption NASA AIRS infrared data on Tropical Cyclone Helen showed that the strongest thunderstorms with the coldest cloud top temperatures (purple) were still off-shore on Nov. 21. Credit NASA JPL, Ed Olsen Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.