Dehradun, Jun 23 (IANS): With most parts of Uttarakhand witnessing overcast skies Sunday and the met department forecasting heavy rain in the next 48 hours, the fate of nearly 20,000 people stranded there after last week's heavy rains seems frighteningly uncertain, officials say.

Officials engaged in rescue operations had Saturday said 20,000 people were still awaiting evacuation from the hill state ravaged by flash-floods and landslides which have claimed hundreds of lives.

While the rescuers say they are doing their best to ensure that the "last living soul" in the rain-ravaged areas is brought back to safety, they admit that airlifting of stranded people may become impossible in rains.

"If the rains restart, our choppers would not be able to fly and the rescue sorties will have to be stopped," said a senior official involved in the relief operations in Uttarakhand.

An officer of the army's Central Command told IANS that heavy rains are expected between June 25 and 27, and that the presence of "multi-layered clouds" would hamper flying.

Heavy rains are expected in the state's Pithoragarh, Uttarkashi and Chamoli districts, which are already disaster-stricken following last week's rains and cloud-burst.

The army has already said that Sunday will be a crucial day for the ongoing rescue operations.

Several sorties had to be abandoned Saturday owing to the dense and heavy cloud cover over the state capital Dehradun and Rudraprayag. Dehradun received some showers too.

An army official said heavy fog has enveloped the valleys around Chamoli town, making air movement "either difficult or confusing". The fog is likely to get denser, as environmentalists say this is a normal phenomenon in the hills if the sun shows up right after heavy rains.

The army rescued 600 people from Kedarnath, Jangalchatti and Rambada Saturday, and 1,800 marooned pilgrims were sent from Guptkashi to Rishikesh in 150 vehicles.

With more than 1,000 major and minor roads washed away in the rains, officials say air rescue is the only way to get trapped people to safety.

However, soldiers of the Indian Army, and troopers of the Indo-Tibetan Border Police (ITBP) and the National Disaster Relief Force (NDRF) are making new routes through the hills and rescuing people on foot.

In all, 1,550 people have been rescued from Pandukeshwar, Ghangharia and Pulna, while more than 5,000 people are still stranded at Badrinath. Around 17,000 people have been evacuated from this region so far.

The state is yet to receive the monsoon showers but the rains last week were 450 percent more than what the region generally gets during this period.

Thousands are feared to have perished in the disaster which Uttarakhand Chief Minister Vijay Bahuguna described as a "Himalayan Tsunami".