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Cyclone Kelvin batters northwest Australia

June 19, 2018
Image of Tropical Cyclone Kelvin

The Suomi NPP satellite's VIIRS instrument captured this image of Tropical Cyclone Kelvin in northwest Australia at 0630 UTC on February 18, 2018. The storm, which initially developed as a low pressure system off Australia's northern coast, was unusual for strengthening after it made landfall. While most tropical systems weaken after crossing land, Kelvin made landfall as a Category 1 storm, then continued to intensify to a Category 2 storm, lashing areas with winds above 90 mph. This imagery shows the storm as it developed a distinct eye over Australia's Great Sandy Desert.

Tropical cyclones that strengthen over land are rare, as these storms are fueled by heat and moisture from the ocean. Occasionally, however, conditions over land may be conducive for further intensification. In this instance, Cyclone Kelvin may have encountered the "brown ocean effect," where the combination of high soil moisture from recent rainfall, and relatively flat terrain helped sustain the storm over land.

Although true-color images like this may appear to be photographs of Earth, they aren't. They are created by combining data from the three color channels on the VIIRS instrument sensitive to the red, green and blue (or RGB) wavelengths of light into one composite image. In addition, data from several other channels are often also included to cancel out or correct atmospheric interference that may blur parts of the image.