Tag Archives: Farafangana

Tropical Cyclone Alvaro Moves East of Madagascar

Tropical Cyclone Alvaro moved east of Madagascar on Tuesday. At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Alvaro was located at latitude 23.1°S and longitude 50.3°E which put it about 150 miles (240 km) east of Farafangana, Madagascar. Alvaro was moving toward the east-southeast at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 999 mb.

Tropical Cyclone Alvaro weakened to the equivalent of a tropical depression before it moved over the Southwest Indian Ocean east of Madagascar on Tuesday. Alvaro began to intensify slowly after it moved back over water. More thunderstorms began to develop in bands revolving around the center of Tropical Cyclone Alvaro. Those thunderstorms generated upper level divergence that pumped mass away to the east of the tropical cyclone. Winds to tropical storm force extended out 75 miles (120 km) from the center of Alvaro’s circulation.

Tropical Cyclone Alvaro will move through an environment somewhat favorable for intensification during the next 24 hours. Alvaro will move over water where the Sea Surface Temperatures are near 27°C. It will move under the southern part of an upper level ridge over the Southwest Indian Ocean. The upper level ridge will produce westerly winds that will blow toward the top of Alvaro’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification, but the shear may not be enough to prevent some intensification. Tropical Cyclone Alvaro could continue to slowly intensify on Wednesday.

The upper level ridge over the Mozambique Channel will steer Tropical Cyclone Alvaro toward the east-southeast during the next 24 hours. On its anticipated track, Tropical Cyclone Alvaro will move farther east of Madagascar. Alvaro will pass south of La Reunion and Mauritius in 36 hours.

Tropical Cyclone Emnati Nears Madagascar

Tropical Cyclone Emnati neared the east coast of Madagascar on Tuesday morning. At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Emnati was located at latitude 20.2°S and longitude 49.9°E which put it about 100 miles (160 km) northeast of Manajary, Madagascar. Emnati was moving toward the southwest at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h). The minimum surface pressure was 962 mb.

Tropical Cyclone Emnati weakened as it neared the east coast of Madagascar. A long eyewall replacement cycle was disrupting the inner core of Emnati’s circulation. The inner eyewall was dissipating slowly. The strongest winds were occurring in the larger outer eyewall. A break in the ring of thunderstorms in the northwest side of the outer eyewall was evident on microwave satellite imagery. Bands of showers and thunderstorms were revolving around the outer eyewall. Storms near the center of Emnati generated upper level divergence that pumped mass away from the tropical cyclone.

The long eyewall replacement cycle produced a large circulation around Tropical Cyclone Emnati. Winds to hurricane/typhoon force extended out 80 miles (130 km) from the center of Emnati. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Emnati was 13.9. The Hurricane Size Index (HSI) was 25.7 and the Hurricane Wind Intensity Size Index (HWISI) was 39.6. Tropical Cyclone Emnati was capable of causing widespread serious damage.

Tropical Cyclone Emnati will move through an environment mostly favorable for intensification during the next 12 hours. Emnati will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Even though Tropical Cyclone Emnati will be in an environment favorable for intensification, the long eyewall replace cycle could cause Emnati to weaken while the inner eyewall fully dissipates. In addition, northwesterly winds blowing around the northern side of Tropical Cyclone Emanti could cause drier air to sink down the eastern side of mountains in Madagascar. The drier air could weaken thunderstorms in the northern part of Emnati’s circulation.

Tropical Cyclone Emnati will move around the northwestern part of a high pressure system over the Southwest Indian Ocean. The high pressure system will steer Emnati toward the southwest during the next 24 hours. On its anticipated track the center of Tropical Cyclone Emanti will reach the east coast of Madagascar in 12 hours. The center of Emnati could make landfall between Nosy Varika and Farafangana. Tropical Cyclone Emnati will be capable of causing widespread serious damage to southern Madagascar. Tropical Cyclone Emnati will bring strong destructive winds and locally heavy rain to southern Madagascar. Heavy rain is likely to cause flash floods in some locations. Widespread electrical outages are likely to occur. Emanti will also cause a significant storm surge along the southeast coast of Madagascar.