Tropical Cyclone Sidr crept steadily north and west over the warm waters of the Bay of Bengal after forming on November 11, 2007. This image shows the storm as observed by NASA’s QuikSCAT satellite on November 11, 2007. At the time, the center of the developing storm sat west of the southern edge of the Andaman Islands. The colors chart out the storm’s wind speed, and not surprisingly, the strongest winds are in the center of the storm. Small barbs show wind direction, and white barbs point to heavy rainfall. On November 12, the Joint Typhoon Warning Center forecast that Sidr would grow to the equivalent of a Category 2 storm, with sustained winds of 170 kilometers/hour (100 mph or 90 knots) by November 14.