In one incident, a group of school children and a driver died when their vehicle was overtaken, authorities said.

Heavy rains also were expected over Dubai in the neighbouring United Arab Emirates and other regions of the Arabian Peninsula.

Civil defence officials gave the death toll for the rains, in which Oman's North Al Sharqiyah province was hardest hit.

The Royal Oman Police and the Omani military deployed to the province to transport citizens out of flooded areas, the state-run Oman News Agency reported.

Heavy rainfall often causes flash flooding in the sultanate, drawing the curious from their homes to nearby dry riverbeds, known in Arabic as "wadi".

In flooding, they can quickly fill and wash away people and vehicles.

In Dubai, authorities expected heavy rains to begin on Monday night and last into Tuesday morning.

The Emirates' National Centre of Meteorology warned of thunder, lightning, rain and possibly hail, with winds reaching up to 70km/h.

Government schools announced they would hold classes remotely on Tuesday and Wednesday.

Australian Associated Press