Airlines Operators Association of Nepal (AOAN) has directed its member helicopter companies to keep their aircraft on standby for possible rescue operations as meteorologists forecast heavy to very heavy rainfall across Nepal over the next five days.

The association issued a circular to its member companies on Wednesday, asking them to remain prepared to launch rescue and emergency operations if floods, landslides or other disasters occur because of adverse weather.

The circular, issued by association president Pratap Jung Pandey, said heavy rainfall and adverse weather were likely in various parts of the country from Friday to Sunday. It urged helicopter operators to exercise heightened caution while conducting flights and remain prepared for possible rescue operations.

The association has nine member helicopter companies: Air Dynasty, Heli Services, Altitude Air, Fishtail Air, Heli Everest, Kailash Helicopter, Basecamp Air, Mustang Helicopter and Prabhu Helicopters. Simrik Air was also included in the association’s circular on standby arrangements.

According to the Civil Aviation Authority of Nepal, the operators have a combined fleet of 33 helicopters. Annapurna Helicopter and Mountain Helicopters are not members of the association.

The association also urged passenger airlines including Buddha Air, Yeti Airlines, Shree Airlines, Tara Air, Summit Air and Sita Air to exercise caution, citing the Department of Hydrology and Meteorology's forecast of heavy rain accompanied by thunderstorms, lightning and strong winds, particularly in Gandaki and Lumbini provinces.

Meteorologists have warned of potentially heavy to very heavy rainfall across Nepal for five days from Thursday and urged people to remain alert.

The warning comes less than a month after a flash flood in the Bhotekoshi corridor killed more than 1,400 people and left thousands missing in Rasuwa and Nuwakot districts. The August 26 torrent, triggered by a glacial collapse, destroyed roads and bridges, buried settlements and damaged hydropower projects. Further heavy rain could hamper ongoing relief and recovery efforts.

The Bay of Bengal in the northeastern Indian Ocean is currently generating a low-pressure system that may bring extremely heavy rain to Nepal from September 24 to 28, according to the Meteorological Forecasting Division of the Department of Hydrology and Meteorology.