Tropical Cyclone Olga weakened over the South Indian Ocean north of Western Australia on Monday. At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Olga was located at latitude 17.5°S and longitude 117.2°E which put it about 250 miles (400 km) north of the Karratha, Australia. Olga was moving toward the southwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 994 mb.

Strong vertical wind shear caused Tropical Cyclone Olga to weaken steadily on Monday. An upper level trough over the South Indian Ocean west of Australia produced strong northwesterly winds that blew toward the top of Olga’s circulation. Those winds caused strong vertical wind shear. The wind shear caused the distribution of thunderstorms in Tropical Cyclone Olga to become asymmetrical. Thunderstorms were occurring in bands in the southeastern part of Olga’s circulation. Bands in the other parts of Tropical Cyclone Olga consisted primarily of showers and lower clouds.

The strong vertical wind shear also caused the pattern of wind speeds around Tropical Cyclone Olga to become asymmetrical. Winds to tropical storm force extended out 145 miles (235 km) in the southern half of Olga’s circulation. Winds to tropical storm force only extended out 75 miles in the northern half of Tropical Cyclone Olga.

Tropical Cyclone Olga will move through an environment that will be unfavorable for intensification during the next 24 hours. Olga will move over water where the Sea Surface Temperatures are near 28°C. However, the upper level trough west of Australia will continue to cause strong vertical wind shear. The strong wind shear will cause Tropical Cyclone Olga to continue to weaken.

Tropical Cyclone Olga will move around the northwestern part of a high pressure system over Australia. The high pressure system will steer Olga toward the southwest during the next 24 hours. On its anticipated track, Tropical Cyclone Olga will gradually move closer to the coast of Western Australia.

Tropical Cyclone Olga brought strong gusty winds to the area around Rowley Shoals. A weather station on Rowley Shoals reported a sustained wind speed of 48 m.p.h. (78 km/h) and a wind gust of 61 m.p.h. (98 km/h). Olga could bring strong gusty winds to Barrow Island during the next 24 hours.