Rapid intensification of Super Typhoon Surigae
2.5-minute interval rapid scan JMA Himawari-8 Infrared Window (10.4 µm) images (above) showed Typhoon Surigae undergoing rapid intensification (ADT | SATCON) to become a Category 4 storm as of 18 UTC on 16 April 2021.A DMSP-16 SSMIS Microwave (85 GHz) image from the CIMSS Tropical Cyclones site (below) displayed a well-defined eye, with distinct spiral bands feeding into the eyewall.
After sunrise, Himawari-8 “Red” Visible (0.64 µm) images (below) showed the relatively compact eye, with hints of low-level mesovortices within the eye.===== 17 April Update =====
![JMA Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]](https://cimss.ssec.wisc.edu/satellite-blog/images/2021/04/h8_ir2-20210417_120217.png)
JMA Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]
Year and date of all 165kt tropical cyclones on record around the world. pic.twitter.com/JLUwjceapf
— Sam Lillo (@splillo) April 17, 2021
An animation of Himawari-8 Infrared images with an overlay of deep-layer wind shear (below) indicated that Surigae was moving through a region of low to moderate wind shear; the storm was also moving across very warm water (SST + OHC). Around the time that Surigae was reaching its peak intensity, a Suomi NPP VIIRS Day/Night Band (0.7 µm) image several hours before sunrise (below) revealed concentric mesospheric airglow waves (reference) propagating away from the energetic Category 5 tropical cyclone. In closer view of time-matched Himawari-8 Infrared and Suomi NPP Day/Night Band images (below), a cluster of bright DNB pixels highlighted the presence of lightning activity along the inner edge of the northern eyewall.