NASA MODIS Image of the Day: January 20, 2013 – Tropical Cyclone Narelle (08S) off Australia
When NASA’s Terra satellite passed over Tropical Cyclone Narelle on Jan. 11 at 0245 UTC the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument captured a visible image of the storm that clearly showed an eye had formed. Satellite imagery indicated that Narelle’s eye was approximately 15 nautical miles (17.2 miles/27.8 km) wide. Satellite imagery also showed that Narelle had become more symmetrical and bands of thunderstorms had become more tightly wrapped into the center than the previous day, indicating a strengthening storm. The Joint Typhoon Warning Center (JTWC) reported on January 11 at 1500 UTC (10 a.m. EST), that Tropical Cyclone Narelle’s maximum sustained winds had increased to 132.3 mph (213 km/h), making the storm a major cyclone and a Category 4 hurricane on the Saffir-Simpson Scale. At that time, Narelle was located about 255 nautical miles (293.4 miles/472.3 km) north-northwest of Learmonth, Australia, and was moving to the southwest at 9.2 mph (14.8 km/h). The storm formed over the southern Indian Ocean on January 7, and strengthened into the cyclone two days later, bringing heavy rain and high winds and flooding to Indonesia. Tropical Cyclone Narelle then took aim at Western Australia, but a sub-tropical ridge of high pressure centered over Western Australia kept Narelle offshore as it skirted the western coastline. Vertical wind shear began to take a toll on the storm by January 13, and at 2100 UTC (8:00 p.m. EST/U.S.) the JTWC issued their final warning on Narelle, which had become an extra-tropical system moving southward over open ocean.
