Super Typhoon Bopha

December 3rd, 2012
Suomi NPP VIIRS 0.64 µm visible and 11.45 µm IR images

Suomi NPP VIIRS 0.64 µm visible and 11.45 µm IR images

Super Typhoon Bopha reached peak intensity (ADT plot | Advisory text) just before making landfall in the island of Mindanao in the Philippines on 03 December 2012. Earlier in the day, a comparison of McIDAS-X images of 375-meter resolution Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel data (above) revealed detailed patterns of cloud top wave structure: (1) the formation of “transverse bands” oriented perpendicular to the flow (which is fairly common in strong tropical cyclones), and (2) an arc-shaped gravity wave train in the northwest quadrant, which was likely propagating outward, away from the storm center. There were also a number of convective overshooting tops which exhibited IR brightness temperatures of -90 to -95º C (yellow enhancement).

MTSAT-1R 10.8 µm IR images (click image to play animation)

MTSAT-1R 10.8 µm IR images (click image to play animation)

McIDAS-X images of MTSAT-1R 10.8 µm IR channel images (above; click image to play animation) showed Super Typhoon Bopha as the eye made landfall around 20 UTC or 4 AM local time. Media reports indicated that there were as many as 270 fatalities as a result of flooding, mudslides, and falling trees.

A few hours prior to landfall, a comparison of McIDAS-V images of Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR data (below; images courtesy of William Straka, CIMSS) again showed a signature of gravity waves propagating outward from the storm center — at this time (17:09 UTC or 1:09 AM local time) these gravity waves could be seen in all four quadrants of the storm top. The eye was not entirely cloud-free, with the Day/Night Band image showing moonlight being reflected off of low-level stratus near the ocean surface.

Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images

Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images

During the 01-03 December period, the MIMIC or Morphed Integrated Microwave Imagery at CIMSS product (below; click image to play animation) showed that Bopha experienced multiple eyewall replacement cycles as it moved south of the island of Palau (where it produced a wind gust of 70 mph at Koror) and toward the Philippines.

Morphed Integrated Microwave Imagery at CIMSS (click image to play animation)

Morphed Integrated Microwave Imagery at CIMSS (click image to play animation)

Bopha had an early storm track (below) that was unusually close to the Equator — in fact, the storm was classified as a typhoon at a latitude of 3.8º N on 30 November, making it the closest typhoon formation to the Equator on record for the West Pacific Basin.

Track of Super Typhoon Bopha

Track of Super Typhoon Bopha