Tropical Cyclone Mitchell was passing near Exmouth in Western Australia on Sunday morning. At 10:00 a.m. EST on Sunday the center of Tropical Cyclone Mitchell was located at latitude 22.0°S and longitude 113.8°E which put the center about 25 miles (40 km) north-northwest of Exmouth, Australia. Mitchell was moving toward the west-southwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h). The minimum surface pressure was 983 mb.
The Australian Bureau of Meteorology issued a Warning that was in effect for the portion of the coast from Onslow to Overlander Roadhouse. The Warning included Exmouth, Carnarvon, and Denham. The Warning extended inland to include Gascoyne Junction.
Even though the center of Tropical Cyclone Mitchell remained offshore, Mitchell was producing strong winds along the coast of Western Australia. A weather station at the Onslow airport measured a sustained wind speed of 59 m.p.h. (95 km/h) and a wind gust of 75 m.p.h. (120 km/h).
Tropical Cyclone Mitchell weakened on Saturday night even though the center of Mitchell remained over water. Southeasterly winds blowing into the southwestern part of Mitchell’s circulation appeared to pull drier air from the interior of Western Australia into the western side of the circulation. The drier air caused many of the thunderstorms in the southwestern part of Tropical Cyclone Mitchell to weaken. Thunderstorms were still occurring in bands in the other parts of Mitchell’s circulation. Since there were fewer thunderstorms near the center of Mitchell, those thunderstorms generated less upper level divergence. Less upper level divergence meant that the thunderstorms pumped less mass away from the tropical cyclone. The removal of less mass caused the surface pressure to increase.
The circulation around Tropical Cyclone Mitchell continued to be small. Winds to tropical storm force extended out 90 miles (145 km) from the center of Mitchell’s circulation.
Tropical Cyclone Mitchell will move through an environment that will be unfavorable for intensification during the next 24 hours. Mitchell will move over water where the Sea Surface Temperatures are near 29°C. However, it will move under the western end of an upper level ridge that is over Australia. The upper level ridge will produce northwesterly winds that will blow toward the top of Mitchell’s circulation. Those winds will cause the vertical wind shear to increase. In addition, Tropical Cyclone Mitchell is likely to continue to pull drier air into its circulation. The combination of more vertical wind shear and drier air will cause Tropical Cyclone Mitchell to weaken slowly during the next 24 hours.
Tropical Cyclone Mitchell will move around the western end of a high pressure system that is over Australia. The high pressure system will steer Mitchell toward the south during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Mitchell will make landfall on the coast of Western Australia near Cape Cuvier and Carnarvon in 12 hours.
Tropical Cyclone Mitchell will bring strong winds and heavy rain parts of Western Australia near Cape Cuvier and Carnarvon. Heavy rain is likely to cause floods in some locations.
Flood Watches are in effect for the Gascoyne River, the Ashburton River, the Fortescue River, the Greenough River, the Murchison River, the Wooramel River, the Pilbara Coastal Rivers, and the Yarra Yarra Lakes District.
