Tropical Cyclone Joyce developed near Western Australia on Wednesday when a Tropical Low moved over the South Indian Ocean.  At 10:00 p.m. EST on Wednesday the center of Tropical Cyclone Joyce was located near latitude 17.0°S and longitude 121.6°E which put it about 80 miles (125 km) north-northwest of Broome, Australia.  Joyce was moving toward the south-southwest at 5 m.p.h. (7 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 990 mb.

A Tropical Low moved from Western Australia off the coast and over the warm water of the South Indian Ocean on Wednesday.  The circulation of the system organized after the center moved over water and the inner core became more well developed.  The Australian Bureau of Meteorology designated the system as Tropical Cyclone Joyce.  A Tropical Cyclone Warning was issued for the portion of the coast from Cape Leveque to De Grey including Broome and adjacent inland parts of Western Australia.  A Tropical Cyclone Watch was issued for the portion of the coast from De Grey to Dampier including Port Headland, Karratha and adjacent inland areas.

The circulation of Tropical Cyclone Joyce exhibited the classical appearance of an organizing tropical cyclone on Wednesday.  There was a well defined low level center of circulation.  Numerous bands of showers and thunderstorms were revolving around the center of circulation.  Storms in the core of Joyce were generating upper level divergence which was pumping mass away from the tropical cyclone.

Tropical Cyclone Joyce will be moving through an environment favorable for intensification during the next day or so.  Joyce will move over water where the Sea Surface Temperature is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  Warm water and little vertical wind shear will allow Joyce to strengthen and it could intensify rapidly.  Tropical Cyclone Joyce is forecast to strengthen into the equivalent of a hurricane/typhoon during the next 36 hours.

Tropical Cyclone Joyce is moving around the western end of a subtropical ridge which is steering Joyce toward the south-southwest.  The ridge is forecast to steer Joyce in a general southwesterly direction during the next several days.   On its anticipated track the center of Tropical Cyclone Joyce could make landfall on the coast of western Australia between Wallal Downs and De Grey in about 36 hours.