Alcide (Southern Indian Ocean)

Nov. 09, 2018 – NASA Satellite Sees Tropical Cyclone Alcide Nearing Madgascar

Tropical Cyclone Alcide continued to linger just northeast of the Island nation of Madagascar in the Southern Indian Ocean when NASA’s Aqua satellite passed overhead and captured an image of the storm.

Aqua image of Alcide
On Nov. 9 the MODIS instrument aboard NASA’s Aqua satellite captured a visible image of Tropical Cyclone Alcide in the Southern Indian Ocean, located northeast of Madagascar. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

On Nov. 9 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite provided a visible light image of the storm. The MODIS image showed a somewhat elongated storm from northwest to southeast with the bulk of clouds in the western quadrant of the storm.

On Nov. 9, the Joint Typhoon Warning Center or JTWC noted that animated multispectral satellite imagery showed that Alcide has lost much of its deep convection (rising air that forms the thunderstorms that make up a tropical cyclone) but maintained its spiral banding, and convection is newly flaring over the low level circulation center.

On Nov. 9 at 10 a.m. EST (1500 UTC), Alcide’s maximum sustained winds had dropped to 80 mph (70 knots/129.6 kph). It was located approximately 487 nautical miles north-northwest of Port Louis, Mauritius. Alcide is moving southward at 1.1 mph (1 knot1.8 kph) and is expected to curve to the northwest.

Because of the storm’s slow movement, it is bringing up cooler waters from below the ocean’s surface, which will in turn, weaken the storm.

The Joint Typhoon Warning Center now expects Alcide to move to the northwest and pass just north of the northern point of Madagascar over the next several days.

By Rob Gutro
NASA’s Goddard Space Flight Center