Christmas 2018 under the threat of Cyclones Cilida and Kenanga

For twenty years or more we have been watching CNN forecasting hurricane movements in the Atlantic. The wonder for me had always been the accuracy with which the paths were predicted while the hurricanes were in their early stages

By Paramanund Soobarah

Last Thursday evening (20 December 2018) around 10:00 p.m. while the country was under a Cyclone Warning Class One because of tropical depression Cilida, I was amazed by what I saw on my computer screen. There in front of me, on the Met Office website, was the forecast track of that depression as well as that of Kenanga, the other one of two depressions surprisingly churning up our part of the Indian Ocean at the same time. Two such depressions in the same area is unusual, but it was the forecast tracks, particularly that of Cilida, that aroused my interest and even wonder. I would have liked to transmit that wonder immediately to Mauritius Times, but it was obviously too late for the Friday paper. But I still think that moment of wonder is still worth recording.

After initially tracking eastwards from Agalega, it recurved sharply to the right by more than 90 degrees to track towards the south-west and continued moving in that direction. We can be sure that this track as depicted was accurate, because it was, by that time, also confirmed by historical data and verified by weather satellite imagery.

If it were to continue moving in that direction it would pass between St Brandon and Tromelin Islands, and pass far to the west of Mauritius and even Reunion: actually it was at the the time still forecast to move that way until about midday or 2.00 pm the following day (Friday). But around that time on Friday a dramatic change was forecast to happen: Cilida would turn left and head south – directly towards Mauritius, our own beloved Island. Fortunately for us the leftward bend was shown to continue, and for the track to settle on a south-easterly course which would take it well to the East of Mauritius, passing between Mauritius and Rodrigues. It must be remembered that at the time these track positions were forecasts, and NOT actual positons.

The wonder in that picture was that our Met office in Vacoas had been able to forecast that movement, with its re-curvature from eastwards to south-westwards and then back to south-eastwards days before the movement had actually taken place. For twenty years or more we have been watching CNN forecasting hurricane movements in the Atlantic. These hurricanes start somewhere in the Mid Atlantic and head westwards towards Haiti and Cuba, and then they turn north and finally north-east, making their way upwards along the eastern states of the US, sometimes passing over the Florida panhandle and sometimes further west over Texas or at any point in between. The wonder for me had always been the accuracy with which the paths were predicted while the hurricanes were in their early stages, still moving westwards in mid-Atlantic. I always dreamed about the day when our own Met Office would be able to forecast cyclone tracks with such accuracy.

That was what, on the screen before me that Thursday evening, our little country, and our little Met Office in Vacoas, had achieved. It did not matter if they were a little, or even a lot, off the mark. They now had the tools, and were confident about using them; they will no doubt keep improving themselves and refining their methods. I feel the same sort of pride in that achievement as Indians probably feel when ISRO launches GSLV and PSLV satellites today using indigenously developed cryogenic (very low temperature) technology. I recall the sadness I felt in the late eighties when the US, USSR, Europe and others banded together to deny India access to that technology.

One intriguing point about the movement of the other cyclone (Kenanga) was that it was forecast to be moving on a track perpendicular to that of Cilida by Monday or Tuesday and moving towards it. That will be an interesting encounter to watch.

We are now a far cry from we were in the days of Cyclone Carol in 1960, when weather data in the Indian Ocean was very scarce, all charts had to be drawn manually based on these scarce data and could only be described as very approximate at best. There were of course no satellites; there weren’t even any computers. But we had giants like Met Director Davy and his colleagues Swan, Sundberg and Padya, who all put their heads together to say late at night that this cyclone was heading directly South, and would pass over us within the ensuing twenty-four hours or less. And it did, with catastrophic results for the country.

On Saturday evening (22 Dec 2018), we all had the good fortune of seeing and listening to the Met Director, Mr Goolaup, during the news bulletin. I was still more impressed. Not only was he absolutely sure of the forecast track of Cilida, he asserted that the effective diameter of the area of cyclonic winds was small enough for it not to affect the Islands, and that he would not therefore be issuing a Class III warning. That was some self-assurance for you! It required great courage and conviction, and absolute confidence in his data and science, to make such a statement.

The sequel proved that he was absolutely right. Our Met Office has passed the grade. We are as good as the best!

* Published in print edition on 28 December 2018