Katia formed from Tropical Depression Twelve over the Atlantic Ocean.
Katia track on SST image of 04 September (257 Kb) This image
represents the average composite sea surface temperature (SST) derived from
NOAA satellite AVHRR data over the 7 days ending 4 September 2011. The
averaging is done to remove clouds. The temperature scale for SST is
22C to 32C. The track of Katia is overlaid on this image.