Hurricane (Typhoon) — Saipan, Guam

2023-10-10 to 2023-10-11 · Saipan, Guam

Event narrative

Bolaven went through the Marianas On Oct 10th as a Category 1 typhoon on the Modified Saffir-Simpson Tropical Cyclone Scale for the Western North Pacific, with winds around 80 mph and a estimated minimum central pressure 982 mb, passing through the channel between the islands of Rota and Tinian. Bolaven then rapidly intensified as it continued northwest and then north-northwest into the Philippine Sea, becoming a 160 mph super typhoon of Category 5 strength on Oct 11th. Bolaven would reach estimated peak intensity of 180 mph on October 12th, with a estimated minimum central pressure of 904 mb, before turning northeast on October 13th, exiting WFO Guam Area of Responsibility, and then eventually becoming an extratropical cyclone in the northern Pacific. The strongest winds recorded on Saipan was by the privately owned Wireless Ridge weather station, elevation about 673 ft above MSL, with a sustained wind of 63 knots (72 mph) and gust of 70 knots (81 mph). The ASOS at Saipan International Airport reported a max sustained wind of 38 knots (44 mph), with a gust of 62 knots (71 mph), and a minimum pressure of 996.3 mb. Tinian, the island just south of Saipan, had a sutron that measured a max wind of 41 knots (47 mph), a gust of 65 knots (75 mph), and a min pressure of 987.9 mb. The highest 24 hour rainfall was recorded by the Tinian sutron, with 3 inches recorded. On Saipan the highest 24 hour rainfall was recorded by a private weather station located at Saipan Palace with 2.43 inches. The ASOS on Saipan recorded 1.71 inches in 24 hours. Across Tinian and Saipan, little structural damage was reported though numerous trees were reported down across Saipan and Tinian, blocking roads. On Tinian, the Department of Fire and Emergency Medical Services noted much of the island experienced power outages. There was also one structure fire sometime after midnight (cause unknown) and by 0130ChST, the fire was contained with all individuals safe; seven people went to shelters.

Wider weather episode

Super Typhoon Bolaven formed in northern Chuuk State to the northeast of Chuuk Lagoon on October 7th and very slowly intensified as it moved west to west-northwest toward the Marianas. Bolaven intensified to a tropical storm on October 8th NNE of Chuuk then was slow to intensify further for the next day. It wasn't until October 10th that Bolaven reached Category 1 typhoon status with maximum sustained winds of 80 mph. At this point, it was located 50 miles ESE of Rota. Bolaven soon passed between the islands of Rota and Tinian, keeping the strongest of the typhoon-force winds over the open waters between the two islands, then began to rapidly intensify as it continued northwest then north-northwest into the Philippine Sea. Bolaven was classified a super typhoon with maximum winds of 160 mph as it continued NNW, keeping west of the far northern Mariana Islands. STY Bolaven reached its estimated peak intensity of 180 mph on 12 October before beginning a turn to the northeast on 13 October and exiting to the north of the WFO Guam Area of Responsibility. No injuries, fatalities, or major damage was reported within the Marianas.

Source: NOAA Storm Events Database, event_id 1144291. Narrative written by the NWS forecast office that issued the report.