Tropical Cyclone Idai Rapidly Intensifies Into Equivalent of Hurricane/Typhoon

Tropical Cyclone Idai rapidly intensified into the equivalent of a hurricane/typhoon over the Mozambique Channel on Sunday.  At 11:00 p.m. EDT on Sunday the center of Tropical Cyclone Idai was located at latitude 17.4°S and longitude 43.2°E which put it about 75 miles (120 km) northwest of Maintirano, Madagascar.  Idai was moving toward the south at 1 m.p.h. (2 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 958 mb.

Tropical Cyclone Idai intensified rapidly on Sunday.  An eye was apparent on satellite imagery,  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Idai.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to hurricane/typhoon force extended out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center.

The Hurricane Intensity Index (HII) for Tropical Cyclone Idai was 17.8.  The Hurricane Size Index (HSI) was 10.7 and the Hurricane Wind Intensity Size Index (HWISI) was 28.5.

Tropical Cyclone Idai will continue to move through an environment favorable for intensification during the next day or two,  Idai will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Idai could intensify into the equivalent of a major hurricane during the next 24 hours.

Tropical Cyclone Idai will move around the eastern end of a subtropical ridge over southern Africa. The ridge will steer Idai toward the west during the next several days.  On its anticipated track Tropical Idai could approach the coast of Mozambique in about four days.  Idai could be the equivalent of a major hurricane at that time.