The atolls of Fais and Ulithi in the Federated States of Micronesia are expected to be hit by Typhoon Maysak overnight.
Emergency declarations were made in the FSM as Maysak caused serious damage and was believed to have caused five deaths in one of the states.
A forecaster with the US National Weather Service on Guam, Derek Williams, said the category five system was reaching its peak intensity with winds of up to 250 kilometres an hour at its centre.
Mr Williams said the atolls of Fais and Ulithi, and their population of just over 1000, were in the super-typhoon's "firing range", which could cause serious damage.
"I mean it's going to be a major, major typhoon for them. We expect around a 10-foot storm surge at Fais. And Ulithi, depending on the exact track, it could have anywhere between six to 10 feet. If it tracks directly over [Ulithi], the entire atoll could be underwater. So it's not a good situation."
Mr Williams said the super-typhoon would move towards the main Yap islands tomorrow morning but should pass far enough to the north that they wouldn't take a direct hit.
Meanwhile, a disaster official in Yap, Raymond Igechep, said people on Fais and Ulithi should be seeking shelter in concrete buildings such as churches and schools.
"We're expecting a full, hard impact on the islands by nightfall. As far as information relayed to us, people are mobilising to the community designated typhoon shelters. So I hope they are all OK when the typhoon hits."
Mr Igechep said there were reports of significant damage in the eastern islands of Yap state.
"They took a full impact on the crops and trees and stuff like that but fortunately there were no lives lost."
However, the central FSM state of Chuuk appeared to have not been so lucky, with unconfirmed reports that five people died there because of the typhoon.
Chuuk also sustained serious damage to infrastructure, houses and crops, and the governor Johnson Elimo has declared a state of emergency.
The FSM President, Manny Mori, said a government vessel carrying relief supplies and medical personnel was bound for Chuuk, and another for Yap.
Relief supplies needed
The director of the National Emergency Management Office, Andrew Yatilman, indicated the FSM would need international assistance in the form of food, water and other supplies.
"And as we have done in the past, we always look to regional as well as international communities for help."
The US National Weather Service said Maysak was likely to weaken as it continued its path west towards the Philippines.