Typhoon In-fa

November 20th, 2015 |

MTSAT-2 Infrared (10.8 µm) image with the track of In-fa [click to enlarge]

MTSAT-2 Infrared (10.8 µm) image with the track of In-fa [click to enlarge]

Tropical Depression In-fa (27W) formed well south of the Marshall Islands in the West Pacific Ocean on 17 November 2015, and proceeded to track northwestward to a position south of Guam on 20 November (above). Following a brief decrease in intensity on 18 September, In-fa began another period of intensification during the 19-20 September period. Rapid-scan (2.5-minute interval) Himawari-8 Visible (0.64 µm) images (below; also available as a large 73 Mbyte animated gif) showed a series of eyewall convective bursts and the occasional appearance of a recognizable eye. (Note: the ABI instrument on the upcoming GOES-R satellite will also have a rapid-scan capability, but at 1-minute or even 30-second intervals)

Himawari-8 Visible (0.64 um) images [click to play MP4 animation]

Himawari-8 Visible (0.64 um) images [click to play MP4 animation]

A longer animation spanning the entire 19-20 September period (below; also available as a large 120 Mbyte animated gif) revealed an improving trend in the overall satellite presentation of In-fa, with the eye becoming well defined by the end of the animation as the tropical cyclone reached Category 3 intensity.  In fact, this became the the 15th Category 3 or stronger typhoon in the Northwest Pacific basin in 2015 – the most on record in any tropical cyclone season by the date of 20 November.

Himawari-8 Infrared (10.4 um) images [click to play MP4 animation]

Himawari-8 Infrared (10.4 um) images [click to play MP4 animation]

A comparison of Suomi NPP VIIRS Infrared (11.45 µm) and Day/Night Band (0.7 µm) images at 1547 UTC (below; courtesy of William Straka, SSEC) showed the coldest cloud-top IR brightness temperatures in the southern hemisphere of the eyewall, along with the nighttime glow of lights from the island of Guam.

Suomi NPP VIIRS Infrared (11.45 um) and Day/Night Band (0.7 um) images [click to enlarge]

Suomi NPP VIIRS Infrared (11.45 um) and Day/Night Band (0.7 um) images [click to enlarge]

A well-defined eye was evident in MTSAT-2 Infrared (10.8 µm) and DMSP SSMIS Microwave (85 GHz) images around 2230 UTC on 20 September (below).

DMSP-19 SSMIS microwave (85 GHz) and MTSAT Infrared (10.8 um) images [click to enlarge]

DMSP-19 SSMIS microwave (85 GHz) and MTSAT Infrared (10.8 um) images [click to enlarge]

Mesovortices within the eye were seen in rapid-scan Himawari-8 Visible (0.64 µm) images beginning late in the day on 20 November as In-fa intensified to a Category 4 typhoon. (below;  also available as a large 50 Mbyte animated GIF).

Himawari-8 Visible (0.64 µm) images [click to play MP4 animation]

Himawari-8 Visible (0.64 µm) images [click to play MP4 animation]

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