Tropical Cyclone 18S 2021

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Satellite images and tracking maps of Tropical Cyclone 18S 2021, January 28 - February 6. Max wind speed 65km/h.

18S is located 361 km (195 nautical miles) south-southwest of Learmonth, Australia, and has tracked west-southwestward at 15 km/h (8 knots) over the past 6 hours.

Satellite imagery shows an exposed low level circulation center (LLCC) which supports the initial position with good confidence. The limited remaining convection south of the LLCC continues to warm as the system takes on subtropical features.

Analysis indicates unfavorable conditions for tropical development with high (20-25 knots) wind shear, limited speed divergence from the westerlies offset to the south, and marginal sea surface temperatures (25-26°C).

18S will continue southward as a subtropical ridge builds east of the system over Western Australia.

Due to the southward track, the system will move under the subtropical westerlies with increasing wind shear (30-45 knots). 18S is expected to full transition into a subtropical cyclone as it tracks poleward under over cooling seas.

Forecast models are in good agreement lending high confidence to the JTWC forecast track, which is positioned near the multi-model consensus.

This is the final warning on this system by JTWC. The system will be closely monitored for signs of regeneration.

Maximum significant wave height is 4.6 meters (15 feet).

Information provided by the Joint Typhoon Warning Center (JTWC).