Rear Adm. Brett Mietus, commander of Joint Region Marianas, left, fills sandbags at Naval Base Guam, April 11, 2026, ahead of Super Typhoon Sinlaku. (Joint Region Marianas)
Guam, including its U.S. military bases, is battening down for a near miss from Super Typhoon Sinlaku, which barreled through the Western Pacific on target to strike the Northern Mariana Islands.
The U.S. territory entered Tropical Cyclone Condition of Readiness 1 at 4 p.m. Monday, meaning potentially destructive winds were expected within 12 hours, according to a news release from Guam’s Joint Information Center.
“[Military] personnel are advised to remain sheltered in place and follow all official guidance until conditions improve,” the center said in the Monday afternoon news release.
Sinlaku was initially forecast to directly impact Guam, but has since moved northward, posing a greater threat to Rota, Tinian and Saipan.
Guam remained under a tropical storm warning and typhoon watch Monday, while the Northern Marianas face a possible direct hit Tuesday afternoon, according to the news release.
Sinlaku will make its closest approach to Guam around 2 p.m. Tuesday, about 103 miles northeast of Andersen Air Force Base, according to the Joint Typhoon Warning Center.
Numerous Guam businesses, including all pharmacies, had closed by Monday afternoon, according to the information center. Those include 7 Day Supermarket, Agana Shopping Center, American Grocery, Cost.U.Less, Guam Premier Outlets, Happy Mart, Home Depot, Kmart, Micronesia Mall, Pay-Less Supermarkets and Village of Donki.
Sailors and volunteers fill sandbags at Naval Base Guam, April 11, 2026, ahead of Super Typhoon Sinlaku. (Joint Region Marianas)
On the island’s military installations — Andersen, Naval Base Guam and Marine Corps Base Camp Blaz — operations narrowed to essential functions. Officials said nonessential services had been curtailed, while critical capabilities such emergency response, command and control, and other key operations remained in place.
“As with any severe weather event, operational adjustments may be made as conditions evolve to prioritize the safety of both civilian and military personnel and maintain the ability to respond as needed,” Navy Lt. Cmdr. Kristina Wiedmann, a spokeswoman for Joint Region Marianas, said by email Monday.
Base access could be affected as conditions worsen, with gates expected to close once sustained winds reach 57 mph, she said. Naval Hospital Guam will remain open for emergency services only.
Military planners are also drawing on lessons from previous storms, and “continue to strengthen resilience through infrastructure improvements and refined preparedness procedures,” Wiedemann said.
“Any changes to the current posture, including additional restrictions or a return to normal operations, will be based on real-time weather conditions and damage assessments,” she added.
While ships and aircraft are often repositioned ahead of major storms, those decisions are made at the installation level, Wiedemann said.
For many on Guam, the approach of Sinlaku has revived memories of Typhoon Mawar, which struck the island in May 2023 with winds of up to 140 mph. It remains the strongest storm to hit the territory since Typhoon Pongsona in 2002.
Mawar uprooted trees, damaged buildings and caused widespread flooding, leaving much of the 2010-square-mile U.S. territory without water. Recovery stretched on for more than a year, with repairs to Andersen’s passenger terminal still underway.
Follow Stars and Stripes’ Pacific Storm Tracker for up-to-date information on the typhoon.
