Three low pressure systems circling the South Pacific region today may potentially form cyclones by the weekend, says  Tonga's Meteorology Department.

“The one in Vanuatu, we are monitoring closely because it looks like it’s going to move east, near Samoa and the Niuas,” he said.

If the low pressure system continues moving east, “there is a possibility we could have a cyclone [forming] by the end of the week or early next week,” he said.

However, the system may change its forecast route.  “It’s still far away, we’re talking a thousand kilometres away”.

As for the other two low pressure systems, he said it is too early to tell where they will head to at this stage.

The low pressure zone near Tonga is causing the hot steamy weather felt across the kingdom, which 'Ofa says is “dragging the hot air from up north”.

The low pressure zone was located 608 km West Southwest of Nuku’alofa at 9am today and was moving south at about 12km per hour.

Tonga MET’s forecast to midnight tomorrow issued at 1pm today warns of strong wind and heavy rain for the Niuas. Vava’u may expect light to moderate west to northwest winds, variable at times, with occasional (possibly heavy) rain.

For Ha’apai, Tongatapu and ‘Eua, light to moderate north to north east winds are expected with isolated showers.

A strong wind warning is also issued for the Niuas coastal waters, Tele-ki-Tonga and Tele-ki-Tokelau coastal waters, as well as the Western waters of all of Tonga.