GOES-16 (GOES-East) Ash RGB images and Dust RGB images (above) showed numerous volcanic plumes emanating from Popocatépetl in central Mexico during the 5-day period from 21 May – 25 May 2023. On 21 May, the airport at Puebla (MMPB) was temporarily closed, due to the potential adverse impact of volcanic ash to aviation (1731 UTC images) — and ash fall occurred within the city. At times the volcanic plumes were either partially or completely obscured by meteorological clouds, but for the most part the majority of eruptive events were well-sampled by the 5-minute GOES-16 imagery.

Even though the Ash RGB and Dust RGB products leverage the same ABI spectral bands, the various RGB components are scaled differently — which in this case led to the ash plumes exhibiting a more notable signature in the Dust RGB images (brighter shades of pink to magenta).

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Direct Broadcast data from the antenna on Guam (processed with CSPP data) at 1558 UTC on 25 May show the structure of a very strong typhoon. Mawar at 1800 UTC was a Super Typhoon with sustained winds of 155 knots. (Blog Post). The toggle above shows I05 (11.45 µm) and Day Night Band visible (0.70 µm) imagery. There are (again) indications of mesospheric gravity waves in the Day Night Band imagery (i.e., concentric light/dark bands surrounding the storm, especially west and north of the storm). The 11.45 infrared imagery shows a very warm eye. In both images, the symmetric nature of the storm is apparent, and strong convection in the outer bands.

At 1650 UTC, Suomi NPP provided I05 and Day Night Band data, shown below. The Mesospheric Gravity Waves are perhaps more noteable in the Suomi NPP Day Night imagery.

Thanks to Douglas Schumacher, SSEC/CIMSS, for the imagery!

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Target Sector (2.5-minute interval) JMA Himawari-9 Visible and Infrared images (above) covered the period +/- 2 hours when Super Typhoon Mawar reached Category 5 intensity at 0600 UTC on 25 May 2023. Mesovortices within the eye were evident in Visible imagery, with the eye exhibiting a “stadium effect” geometry (two signatures that are often associated with intense tropical cyclones).

A DMSP-17 SSMIS Microwave (85 GHz) image at 0911 UTC from the CIMSS Tropical Cyclones site (above) showed Mawar to the west of Guam, with a well-defined, completely closed eyewall along with a spiral band wrapping into the storm center from the south. Later in the day, Mawar further intensified to 155 knots at 1800 UTC (JTWC advisory | ADT | SATCON | D-MINT | D-PRINT) — and a DMSP-18 SSMIS Microwave image at 1905 UTC (below) revealed a distinct pair of spiral bands.

As also mentioned in this blog post, a Suomi-NPP VIIRS Day/Night Band (0.7 µm) image valid at 1655 UTC (below) revealed mesospheric airglow waves (reference) radiating hundreds of miles northward through westward away from Mawar — these vertically-propagating gravity waves were generated by deep convection within Mawar’s eyewall.

A long animation of Himawari-9 “Clean” Infrared Window (10.4 µm) images (below) showed that the eye of Mawar exhibited a small amount of trochoidal motion during the day.

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Typhoon Mawar wobbled north during the day on 24 May and moved through the Rota channel between the islands of Guam to the south and Rota to the north, as shown in the animation of Himawari-9 Target Sector Band 3 (Visible, 0.64 µm) imagery above. The track path from the Joint Typhoon Warning Center, below, shows the 0900 UTC position just north of Ritidian Point on Guam. Typhoon conditions are widespread over Guam however with widespread heavy rain, winds and lightning.

Waves at the Ritidian Buoy exceeded 28 feet in height!

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There is a Direct Broadcast antenna at the forecast office in Guam, and it collected imagery during the storm. The image below, from MetopB, shows 12 µm brightness temperatures at 1205 UTC on 24 May 2023. At this time, typhoon winds continued to affect the island although the center of the eye was

NOAA-20 overflew the storm shortly after 0300 UTC on 24 May 2023, and the Day Night band imagery from that pass is shown below. At that time, the storm was still east of Guam.

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