Super Typhoon In-fa has regained strength, packing maximum sustained winds of 150 miles per hour as it approaches the Northern Islands of the Commonwealth of the Northern Mariana Islands (CNMI).
The US National Weather Service (NWS) said the category 4 storm is expected to pass near or over Agrihan on Friday afternoon or evening.
Typhoon warnings remain in effect for Agrihan, Pagan, and Alamagan, where destructive winds are expected.
At 4am Friday, In-fa was located about 290 miles east-southeast of Agrihan and 295 miles east-northeast of Saipan, moving west at 18 miles per hour.
NWS meteorologist Landon Aydlett said satellite imagery showed a powerful, well-organised storm with a large, clearly defined eye.
He said In-fa appeared to have reached peak intensity and was expected to weaken gradually as it moved through the Marianas.
In-fa is the fifth super typhoon to threaten or pass near the region this year, following Sinlaku in April, Bavi in July, Choi-wan in early October, and Champi less than two weeks ago.
Choi-wan moved north of the Marianas before strengthening into a super typhoon, while Champi narrowly missed southern Guam before reaching super typhoon strength as it moved away from the islands.
The region appears fortunate that In-fa is tracking well north of the main population centres of Guam, Rota, Tinian, and Saipan, sparing them the worst of the storm.
However, the Northern Islands remain at risk, particularly Agrihan, where the storm could pass directly overhead. The remote islands are believed to have only three CNMI residents, although that figure has not been independently confirmed.
Unlike Sinlaku, which moved slowly through the Marianas in April, In-fa is travelling at 15 to 20 miles per hour and is expected to pass through the island chain relatively quickly.
Guam, Rota, Tinian, and Saipan are expected to experience generally favourable weather conditions, although dangerous marine conditions remain a major concern.
Saipan and Tinian are under a high surf warning, with waves of 12 to 18 feet expected, along with possible minor coastal flooding and seas reaching 14 feet.
Guam and Rota are under a high surf advisory, with waves of 10 to 14 feet and seas reaching 10 feet.
High rip current risks remain in effect through Saturday across all four islands.
Residents have been advised to avoid dangerous surf and stay out of the water until conditions improve.
