Powerful Typhoon Mawar Approaches Guam

Powerful Typhoon Mawar was approaching Guam on Tuesday morning. At 11:00 a.m. EDT on Tuesday the center of Typhoon Mawar was located at latitude 12.4°N and longitude 145.8°E which put it about 110 miles (175 km) southeast of Guam. Mawar was moving toward the north-northwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h). The minimum surface pressure was 920 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.

Typhoon Mawar strengthened to the equivalent of a strong Category 4 hurricane on the Saffir-Simpson Scale on Tuesday morning. A circular eye with a diameter of 20 miles (32 km) 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.

The size of the circulation around Typhoon Mawar increased as Mawar appeared to go through a quick eyewall replacement cycle. Winds to typhoon force extended out 40 miles (65 km) from the center of Mawar’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of Typhoon Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 33.3. The Hurricane Size Index (HSI) was 15.6 and the Hurricane Wind Intensity Size Index (HWISI) was 48.9. Mawar was similar in intensity to Hurricane Ian when Ian hit Southwest Florida in 2022. Typhoon Mawar was a little smaller than Hurricane Ian was.

Typhoon Mawar will move through an environment favorable for a powerful typhoon 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 a little more during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then another eyewall replacement cycle could begin. Another eyewall replacement cycle would cause Typhoon Mawar to weaken temporarily.

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 northwest during the next 24 hours. On its anticipated track, the core of Typhoon Mawar will reach Guam in 12 hours. Mawar will be the equivalent of a major hurricane when it reaches the Marianas. Typhoon Mawar will bring strong winds and locally heavy rain to Guam, Rota, Tinian and Saipan. The core of Mawar with the strongest winds could move over Guam. Typhoon Mawar will be capable of causing regional severe damage when it reaches Guam. 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. The subtropical high pressure system will steer Typhoon Mawar more toward the west-northwest after it moves west of Guam.