Cyclone Batsirai reaches Category 4 intensity
EWS-G1 Infrared Window (10.7 µm) images [click to play animated GIF | MP4]
A DMSP-17 SSMIS Microwave (85 GHz) image from the CIMSS Tropical Cyclones site (below) displayed evidence that Batsirai had recently completed an eyewall replacement cycle (ERC), with the faint signature of the original small-diameter eye surrounded by the new large-diameter eye. This ERC process — seen in a 48-hour MIMIC-TC animation — initiated Batsirai’s gradual decline in intensity.
EWS-G1 Visible (0.63 µm) images (below) showed that the small eye was initially cloud-filled, but eventually cleared during the day on 02 February — to reveal the possible existence of eye mesovortices (although such features are difficult to diagnose using 30-minute images) .EWS-G1 Visible (0.63 µm) images [click to play animated GIF | MP4]