Cyclone Ilsa makes landfall in Australia
JMA Himawari-9 “Red” Visible (0.64 µm, left) and “Clean” Infrared Window (10.4 µm, right) [click to play animated GIF | MP4]
A Suomi-NPP ATMS Microwave (183 GHz) image from the CIMSS Tropical Cyclones site (below) displayed a closed eyewall structure at 0543 UTC, with a spiral band extending southward.
A RCM-3 SAR image at 1030 UTC (source) is shown below; the peak SAR-derived radial velocity was 144.36 knots within the northeast quadrant of Ilsa. Himawari-9 Infrared (11.2 µm) images (below) included an overlay of deep-layer wind shear at 1200 UTC — which showed that Ilsa was moving through an environment of low shear (as it traversed warm Sea Suface Temperatures). A GMI Microwave image at 1821 UTC (above) and a DMSP-18 SSMIS Microwave image at 2006 UTC (below) revealed that Ilsa’s closed eyewall remained intact for several hours after the storm had moved inland, while maintaining Category 4 intensity (as of 1800 UTC).