Coast KZN

24 Jan 2022

First named tropical system of 2021/22 cyclone season

Tamlybn Jolly (Zululand Observer) Picture: SAWS. Tropical storm Ana was named this past weekend

This weekend saw the first named tropical system of the 2021/22 tropical cyclone season for the Southwest Indian Ocean Basin.

Towards the end of last week, a tropical low began rapidly intensifying over the open ocean to the northeast of Madagascar, northwards of Mauritius and Reunion islands.

‘There was much interest on the part of the meteorological community, as well as the general public, as this system (provided it intensified sufficiently) was a strong candidate to be the first named tropical system within the Southwest (SW) Indian Ocean Basin,’ said the SA Weather Service (SAWS) on Monday.

To qualify to be named, a tropical low pressure system must reach at least 63 km/h.

‘Over the weekend, the system swirled gradually from east to west over central and northern Madagascar, temporarily losing intensity due to surface friction with the landmass, as well as the absence of the release of latent heat energy from the ocean surface (the main energy driver for tropical cyclones).

‘On Sunday, the system intensified as it slid into the warm, tropical waters of the Mozambique Channel, with the storm becoming more ‘organised’ in structure. ‘Overnight, the system continued to intensify, reaching Moderate Tropical Storm intensity in the early hours of Monday morning, leading to its official naming of ‘Ana’.

‘The system consistently tracked predominantly westwards and by local sunrise on Monday morning, was lying just off the northern Mozambican coastline between Angoche and Mogincual.

According to Storm Report SA, earlier today (Monday), Ana’s average 10 minute wind speed was 75 km/h with maximum estimated gusts of 100 km/h. Her centre pressure was 992 hPa and she was moving west at 19 km/h.

Ana is not expected to pose a direct threat to South Africa