Typhoon Mawar Hits Guam

Typhoon Mawar hit Guam early on Wednesday. At 5:00 a.m. EDT on Wednesday the center of Typhoon Mawar was located at latitude 13.7°N and longitude 144.9°E which put it about 20 miles (30 km) east-southeast of Andersen Air Force Base, Guam. Mawar was moving toward the northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 160 m.p.h. (265 km/h). The minimum surface pressure was 937 mb.

Typhoon Warnings were in effect for Guam and Rota. Tropical Storm Warnings were in effect for Tinian and Saipan. Typhoon Watches were also in effect for Tinian and Saipan.

Powerful Typhoon Mawar brought strong, gusty winds and heavy rain to Guam early on Wednesday. A weather station at the Guam International Airport (PGUM) reported a sustained wind speed of 71 m.p.h. (115 km/h) and a wind gust of 105 m.p.h. (170 km/h). Mawar was also bringing strong winds and rain to Rota, Tinian and Saipan.

Typhoon Mawar was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale when it hit Guam. The size of the circulation around Typhoon Mawar increased when an eyewall replacement cycle occurred in the the core of Mawar’s circulation. Winds to typhoon force extended out 40 miles (65 km) from the center of Typhoon Mawar. Winds to tropical storm force extended out 145 miles (225 km) from the center of Typhoon Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 28.3. The Hurricane Size Index (HSI) was 17.8 and the Hurricane Wind Intensity Size Index (HWISI) was 46.1. Mawar was not quite as strong as Hurricane Ida was when Ida hit Southeast Louisiana in 2021, but Mawar was bigger than Ida was.

Typhoon Mawar was in the latter stages of an eyewall replacement cycle when it hit Guam on early on Wednesday. A small circular eye was at the center of Mawar’s circulation. A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Mawar. Storms near the core of Mawar’s circulation generated strong upper level divergence that pumped mass away from the tropical storm in all directions. The removal of mass continue to caused the surface pressure to remain low.

Typhoon Mawar will move through an environment favorable for intensification during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western part of the axis of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Typhoon Mawar could intensity during the next 24 hours after it completes the current eyewall replacement cycle.

Typhoon Mawar will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the west-northwest during the next 24 hours. On its anticipated track, Typhoon Mawar will move away from the Marianas later today. Mawar will continue to bring strong winds and locally heavy rain to Guam, Rota, Tinian and Saipan during the next few hours. Typhoon Mawar is capable of causing regional severe damage in Guam. Widespread power outages are possible. Heavy rain is likely to cause flooding. A Flood Watch is in effect for Guam. Mawar will also cause a destructive storm surge along the coast of Guam. Weather conditions in the Marianas will improve slowly when the core of Typhoon Mawar moves farther to the west.