Tropical Cyclones Giovanna & Thirteen Struggling
Tropical Cyclone Giovanna has been drifting to towards the southern direction for the last few days after delivering a pounding to the island nation of Madagascar. The system has remained with sustained wind speeds of 55 knots. Wind shear is low over the system, at 5-10 knots due to an anti-cyclone centered over the eastern half of Giovanna. A report from February 15th has said that the death toll from Giovanna so far has risen to 16, and may unfortunately continue to rise in the near future. atleast 65 are injured from the system, and over 11,000 people are homeless.
Satellite image of Giovanna over Madagascar on the 14th dropping torrents of rainfall, credit: NASA
Forecast For Giovanna
Giovanna should continue moving towards a general southeast to east direction in the next day or so, while cold water temperatures begin to rob the system of its fuel source. As the system moves in this direction, land interaction from southern Madagascar will also begin taking its toll on the system again, and Giovanna will slowly weaken to a post tropical cyclone during the next 2-3 days. Dry air lies to the systems west, and this may be able to penetrate into the system due to the lack of deep convection on the northern side. Southern Madagascar should watch this system for the threat of potentially heavy rainfall.
Tropical Cyclone Thirteen Struggling
Tropical cyclone Thirteen was once forecast to make it to a high end category 2 system, but an unexpected weakening cyclone took place yesterday morning. The system has remained at an intensity of 35 knots throughout the last 24 hours, and only expected to strengthen slightly. Dry air may be effecting the system as seen on MIMIC-TPW loops, with some dry air to the systems south and west, trying to make its way into the system from the west. Convection has struggled to sustain with the system, with a few clusters over the LLCC.
IR satellite image of the South Indian Ocean. 13S(Thirteen) is located towards the center.
Forecast For 13S
A subtropical ridge lies to the south of the system, and this should guide Thirteen to the west-southwest for the next few days. As Thirteen gets closer to Madagascar, the system will begin a turn to the southwest on the northwest periphery of the ridge. Sea surface temperatures(SST's) beneath and around the system are about 29-30C, and will remain in this range as Thirteen passes over them. as Thirteen begins its turn towards the southwest in a few days, water temperatures will be cooler, at 27-28C. The system will also be battling dry air all the way through if convection cannot hold itself together. This lack of a Central Dense Overcast(CDO) also makes Thirteen vulnerable to wind shear, but wind shear will not be a problem for atleast the next 24 hours as an anti-cyclone lies over the system. This decreases the shear to the low range of 5-10 knots. The islands of Rodrigues, Mauritius, and Reunion should watch this system as it moves through the forecast track nearing these islands.
Elsewhere In The Tropics
Tropical Depression One has formed in the southern half of the South China Sea, and is on its way to Vietnam. Only slight strengthening is expected before landfall.
The NOGAPS develops a system south of Indonesia in roughly 5 days, a second small weak system in 7 days, and another weak system in 8 days. The GFS shows no TC development in the S Indian, but tries consolidating a system in the western half of the Arafura Sea in 8 days.
That is it for today, thanks all for stopping in and I hope you all have a blessed weekend ahead of you!