By Scott Lindstrom •
Typhoon Koppu hit the northern Philippines island of Luzon on Saturday 18 October. The 4-panel mp4 animation above (Click here for an animated gif) shows the 3 water vapor infrared channels (6.2 µm, 6.9 µm and 7.3 µm) and the window infrared channel (10.35 µm) from the Himawari-8 satellite. There is value in three water vapor channels because the shorter wavelength (6.2 µm) better captures high-level moisture whereas the longer wavelength better captures mid-level moisture. Cirrus is readily apparent in the 6.2 µm channel; tropical cumulus is more readily apparent underneath cirrus in the 7.3 µm channel. Compare the two channels in this animation, for example, or in this one. The three water vapor channels on Himawari-8 (similar to the 3 that will fly on the GOES-R ABI instrument) give a three-dimensional view of atmospheric moisture. All four channels above show the approach of Koppu towards Luzon, with the ragged eye filling rapidly at landfall. The structure of Koppu’s eyewall is depicted above in a 24-hour morphed animation of microwave data (Source, as referred to from here). The nearly complete eyewall rapidly loses its integrity as the storm moves onshore. Total Precipitable Water (below, taken from the MIMIC Total Precipitable Water Site) shows Koppu on the northern edge of the rich moisture source that is the Intertropical Convergence Zone (Typhoon Champi is to Koppu’s east). Notably, the storm stalled over Luzon after making landfall; flooding rainfalls occurred. Himawari-8 also captured the evolution of the storm in visible imagery. The full-resolution animation from 0100-0930 UTC on 17 October is shown below (a slower animation is available here). Periodic bursts of deep convection are apparent in the curved bands near the storm center. These convective bursts are better resolved with the 10-minute imagery from Himawari-8 than from 15-minute data from MTSAT-2 (or COMS-1).Categories: GOES-R, Himawari-8, Other Satellites, Tropical cyclones