Tropical Cyclone Harold formed west of Guadalcanal on Thursday.  At 8:00 a.m. EDT on Thursday the center of Tropical Cyclone Harold was located at latitude 10.0°S and longitude 157.8°E which put it about 150 miles (240 km) west-southwest of Honiara, Solomon Islands.  Harold was moving toward the east-southeast at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 999 mb.

A distinct low level center of circulation developed in an area of thunderstorms over the southern Solomon Sea west of Guadalcanal on Thursday and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Harold.  The circulation around Harold was still organizing.  Bands of strong thunderstorms developed west of the center of circulation.  Other bands of showers and thunderstorms developed in the eastern periphery of Tropical Cyclone Harold.  Storms west of the center of circulation generated upper level divergence which pumped mass away from the center of circulation.  Winds to tropical storm force extended out 90 miles (150 km) from the center.

Tropical Cyclone Harold will move through an environment favorable for intensification.  Harold will move over water where the Sea Surface Temperature is near 30°C.  It will move around the southwestern end of an upper level ridge over the South Pacific Ocean.  The ridge will produce northwesterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Cyclone Harold will intensify and it will strengthen into the equivalent of a hurricane/typhoon.  Harold could intensify rapidly when the inner core becomes fully developed.

The upper level ridge will steer Tropical Cyclone Harold toward the southeast during the next few days.  On its anticipated track Harold could reach Rennell Island in 12 hours.  Tropical Cyclone Harold will bring gusty winds and locally heavy rain to Guadalcanal, San Cristobal and Rennell Island.  Harold could reach Vanuatu within 72 hours.  Tropical Cyclone Harold is very likely to be the equivalent of a hurricane/typhoon when it reaches Vanuatu.