Oman’s Civil Aviation Authority on Monday warned that some areas could experience 80 millimetres of rain in just 24 hours.
Residents were warned to avoid wadis, desist from swimming and exercise caution on the roads.
“Due to the expected heavy thunderstorms that are likely to fall … which in some areas may range from 20 to 80mm within 24 hours, the Civil Aviation Authority advises all to take precautions during rainfall and check the sea state report before sailing,” it said on Monday, in an alert carried by Oman Meteorology, the country’s weather bureau.
Authorities forecast thunderstorms across the Hajar Mountains and in “adjacent areas” such as Buraimi, Batinah, Al Dhahirah and Al Dakhiliyah. They also warned of flash floods, hail, dust storms that cut visibility and waves of up to 4 metres in the Arabian Sea.
More of the same is anticipated on Tuesday and Wednesday as the low pressure systems roll in from India.
Local media also reported the Royal Oman Police warned people to stay away from valleys that are prone to flooding and told motorists not to risk crossing valleys and to leave a sufficient distance between vehicles while driving in the rain.
The force reported on June 29 that it had detained a man in Jebel Akhdar who it said drove through a flooded wadi.
Footage posted to social media by the force shows the man's SUV stuck in surging floodwaters.
The low pressure systems drift across the ocean from India, which is currently experiencing the monsoon.
Some of these systems also cause the phenomenon known as 'khareef", which sees parts of southern Oman turn green from a period of sustained rainfall.
Khareef starts in mid-June and ends typically around the end of August.
The UAE, meanwhile, could also experience some light rain over the next few days.
The National Centre of Meteorology on Monday said there was a chance of showers throughout the week, chiefly in eastern areas of the country.
“[It will be] partly cloudy to cloudy at times, especially eastward [and it] might be convective by afternoon with a probability of light rainfall, the NCM forecast for Tuesday.