Tropical Cyclone Oma Spins Northwest of Vanuatu

Tropical Cyclone Oma continued to spin over the Coral Sea northwest of Vanuatu on Thursday.  At 7:00 p.m. EST on Thursday the center of Tropical Cyclone Oma was located at latitude 15.3°N and longitude 165.1°E which put it about 260 miles (420 km) northwest of Port Vila, Vanuatu.  Oma was nearly stationary.  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 979 mb.

Tropical Cyclone Oma exhibited evidence of greater organization on Thursday.  The inner end of a rainband wrapped more tightly around the center of circulation.  Other bands of showers and thunderstorms also exhibited greater organization.   Storms around the center of circulation generated more upper level divergence which pumped mass away from the tropical cyclone.  Winds to tropical storm force extended out about 200 miles (320 km) from the center of circulation.

Once Tropical Cyclone Oma starts to move, it will move through an area favorable for intensification.  Oma will move over water where the Sea Surface Temperature is near 30°C.  It will move into a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Oma will be likely to intensify and it will likely strengthen into the equivalent of a hurricane/typhoon.

Tropical Cyclone Oma has been in an area where the winds at the steering level were weak and it has moved little during the past several days.  An upper level ridge east of Oma is forecast to strengthen during the next few days.  When the ridge strengthens, it will start to steer Tropical Cyclone Oma toward the southwest.  On its anticipated track Oma will move slowly away from Vanuatu and it could be north of New Caledonia in a few days.