Tropical Cyclone Fantala showed a very clearly defined eye as the storm reached Category 5 level in mid-April.
By Jochen Kerkmann (EUMETSAT)
Fantala became a named Tropical Cyclone on 11 April with maximum winds of around 63 km/h (40 mph). By 18 April the cyclone had intensified into a powerful Category 5 storm with maximum sustained winds of more than 280 km/h (175 mph).
On the Meteosat-10 images from 18 April at 04:00 UTC (Figure 1) a very well-developed eye of about 44 km diameter could be clearly seen.
On Figure 2, the HRV image from 18 April, 13:30 UTC, the overshooting tops can be clearly seen illuminated by the evening sun.
An overshooting convective cloud top (OT) is a dome-like protrusion above a cumulonimbus anvil, often penetrating into the lower stratosphere. It is a manifestation of a very strong updraft in the convective cloud.
OTs can be most easily identified in the high resolution visible channel imagery as the lumpy textured appearance, although only during daytime.
The VIIRS instrument on Suomi-NPP also captured imagery of the eye of Tropical Cyclone Fantala when it was a Category 5 storm.
It was reported that the Seychelles island of Farquhar suffered significant damage overnight 17 April into 18 April, after Fantala passed over the archipelago's outer island.
No injuries were reported despite the fact the cyclone brought winds of up to 345 km/h (214 mph).
The Meteosat-10 IR animation (Figure 3) over the area around the Farquhar islands shows the moment when Fantala crosses the southern Farquhar island.
At around 15.15 to 15.30 UTC, the island is in the eye of the tropical cyclone.
Infrared animated gif
High Resolution Visible
About two hours before the eye crossed Farquhar, the High Resolution Visible image (Figure 4) was captured. Again the eye of Fantala can be clearly seen, as can the overshooting tops, illuminated by the morning/evening sun.
Subsequently, Madagascar did not get much rain, there were some large swells and storm surges.
Dan Lindsey, an atmospheric scientist with NOAA/NESDIS, tweeted an infrared image from 17 April at 22:45 UTC (Figure 3).
The MODIS instrument on the NASA-owned Terra satellite also captured the clear eye of the cyclone, as shown on the MODIS Band 1 (VIS0.6) image at 500 m resolution, 17 April at 6:45 UTC.
The Joint Typhoon Warning Center forecast from 17 April suggested that Fantala would turn round and move back towards the east later in April.
The tropical cyclone began to weaken late on 18 April, with maximum sustained winds of 193 km/h (120 mph) being recorded at 06:00 UTC on 19 April.
This is partly due to its unusual track, moving back the same way it approached Madagascar, over waters that it already mixed up previously, thus weakening the intensity.
The progress of Tropical Cyclone Fantala, as it passed over the Indian Ocean towards Madagascar, intensifying as it went, can be seen on the Meteosat-10 Airmass RGB, imagery (Figure 6).
Satellite Images Illustrate the Power of Category 5 Tropical Cyclone Fantala Near Madagascar (The Weather Channel)
Cyclone Fantala in the Indian Ocean (CIMSS Blog)
Joint Typhoon Warning Center (JTWC) warning
Tropical cyclone ‘Fantala’ hits Seychelles island of Farquhar; infrastructure damaged (Seychelles News Agency)
Record cyclone in the Indian Ocean (Wetter Online)