Tropical Cyclone Maila strengthened to the equivalent of a major hurricane as it moved slowly over the Solomon Sea on Monday night. At 5:00 a.m. EDT on Tuesday the center of Tropical Cyclone Maila was located at latitude 9.9°S and longitude 156.5°E which put the center about 605 miles (970 km) east of Port Moresby, Papua New Guinea. Maila was moving toward the east at 2 m.p.h. (3 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h). The minimum surface pressure was 953 mb.
Tropical Cyclone Maila intensified to the equivalent of a major hurricane on Monday night. A circular eye was present at the center of Maila’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Maila. Storms near the center of Maila generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass caused the surface pressure to decrease.
The distribution of wind speeds around Tropical Cyclone Maila was fairly symmetrical. Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Maila’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of Tropical Cyclone Maila.
The Hurricane Intensity Index (HII) for Tropical Cyclone Maila is 20.6. The Hurricane Size Index (HSI) is 16.5 and the Hurricane Wind Intensity Size Index (HWISI) is 37.1. Tropical Cyclone Maila is similar in intensity to Hurricane Rita when Rita hit Southwest Louisiana in 2005. Maila is smaller than Rita was.
Tropical Cyclone Maila will continue to be in an environment that will be mostly favorable for intensification during the next 24 hours. Maila will be over water where the Sea Surface Temperatures are near 30°C. It will be under the middle of an upper level ridge that is over the Solomon Sea. The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear. Since Tropical Cyclone Maila has been moving slowly over the Solomon Sea, the strong winds near the surface of the ocean are mixing cooler water to the surface. If enough cooler water mixes to the surface of the ocean, then the cooler water could stop the intensification of Maila. Tropical Cyclone Maila could intensify slowly during the next 24 hours, unless too much cooler water mixes to the surface of the ocean.
Tropical Cyclone Maila will continue to be in a region where the steering winds are weak during the next 24 hours. Tropical Cyclone Maila is forecast to meander over the Solomon Sea because the steering winds are weak. A high pressure system is forecast to develop over the Coral Sea later this week. The high pressure system will steer Maila toward the west after it develops.
Elsewhere over the South Pacific Ocean, Tropical Cyclone Vaianu passed southwest of Fiji. At 5:00 a.m. EDT on Tuesday the center of Tropical Cyclone Vaianu was located at latitude 19.7°S and longitude 175.6°E which put the center about 175 miles (285 km) southwest of Nadi, Fiji. Vaianu was moving toward the south-southeast at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h). The minimum surface pressure was 954 mb.