Summary of the evolution of Gelena over Mascarenes region

Brief on Evolution of Gelena in the Mascarenes region (5 to 15 February 2019) under National News

On 5 Feb at 19h00 (Mauritian Time) , Gelena under formation was located near 15.8°S 64.3°E. It was 912 km east-northeast of Port Louis, Mauritius

On 6 Feb. at 14h20 (Mauritius Time) satellite provided a visible image of Tropical Storm Gelena in the Southern Indian Ocean. The image (12.3°S 53.4°E) showed the storm developing an eye, with bands of thunderstorms wrapping into the low-level centre.

On 7 Feb., 2019, at 19h00 (Mauritius Time) the NASA’s Terra satellite captured a visible image of Tropical Cyclone Gelena (near 13.1°S 53.7 °E). The visible-light image showed bands of thunderstorms wrapping into “an intermittent eye feature.” The western quadrant had the bulk of clouds and thunderstorms that extended to the northern tip of Madagascar. Gelena is a Category 1 hurricane on the Saffir-Simpson hurricane scale with winds of 140km/hr n Feb. 8, a tropical cyclone warning class 2 is in force at Mauritius and Rodrigues.

On 8 Feb at 14h05 (Mauritius Time) was located near latitude 15.7°S 55.3°E that’s about 500 km north-northwest of Port Louis, Mauritius. Maximum sustained winds were near 195 kph) and strengthening. On the day, a tropical cyclone warning class 2 came into force at Mauritius and Rodrigues.

On 9 February 2019, at 12H16 (Mauritius Time) GELENA had intensified considerably to Category 4 and represented a threat to Rodrigues

On 10 February with gusts up to 160km/h hit Rodrigues Island.  90% of the 40 000 inhabitants were left without electricity, and 142 people have been evacuated to refuge centres. The main damage reported is due to fallen trees, with blocked roads and broken electricity cables and phone lines. The official cyclone warning has been lifted and only a high wave warning for Rodrigues remains valid over Sunday. The cyclone passed some 50 km to the South-West of the Island at 03h00 LT.

On 11Feb, 2019 at 19h00 (Mauritius Time) , westerly wind shear pushed the bulk of clouds and storms east of the centre. Wind shear is a measure of how the speed and direction of winds change with altitude. Gelena was located near 24.6°S 70.3°E, approximately 1375 km east-southeast of Port Louis, Mauritius.

On 12 Feb 2019 at 13h18 (Mauritius Time), the clouds are being pushed eastward by strong westerly winds. Gelena was located approximately at 25.5°E and 75.5°E att about 1780 km  east-southeast of Port Louis, Mauritius. The tropical storm is moving to the east-southeast. Because Gelena is expected to move over cooler sea surface temperatures and the wind shear is expected to persist, the storm is forecast to dissipate in two days.

On 13 Feb., at 19h00 (Mauritius Time)  the image showed bands of thunderstorms spiralling into a cloud-filled, but defined low level circulation with the bulk of its associated convection and clouds pushed eastward from westerly winds. It was cantered near 26.0°S 79.2°E, 2200km east-southeast of Port Louis, Mauritius. It was moving east-southeast.

On 14 Feb., at 11h45 (Mauritius Time) NASA’s Aqua satellite image shows Gelena’s clear low level centre of circulation, and the bulk of the tropical cyclone’s clouds pushed south of the centre due to strong northerly wind shear. It was centred at  28.6°S 86.6°E at approximately 2730km  south-southeast of Diego Garcia, and has tracked east-south eastward.

 On 15 February 2019, Galena had reached the extra-tropical stage.