Tag Archives: Rota

Tropical Storm Bebinca formed near Guam on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Bebinca located at latitude 13.6°N and longitude 144.0°E which put the center about 20 miles (30 km) southwest of Guam. Bebinca was moving toward the west-northwest at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 999 mb.

Tropical Storm Warnings were in effect for the coastal waters of Guam, Rota, Tinian and Saipan.

A low pressure system near Guam strengthened on Tuesday and the Japan Meteorological Agency designated the system as Tropical Storm Bebinca. Bebinca brought wind and rain to the Marianas. A weather station at Guam International Airport (PGUM) reported a sustained wind speed of 28 m.p.h. (45 km/h) and a wind gust of 45 m.p.h. (73 km/h).

The circulation around Tropical Storm Bebinca was exhibiting more organization on Tuesday afternoon. More thunderstorms developed near the center of Bebinca’s circulation. Thunderstorms also formed in bands in the eastern side of Tropical Storm Bebinca. Bands in the western side of Bebinca’s circulation consisted primarily of showers and lower clouds. Storms near the center of Bebinca generated upper level divergence that pumped mass away from the tropical storm. The removal of mass caused the pressure to decrease.

The distribution of winds speeds in Tropical Storm Bebinca was asymmetrical. Winds to tropical storm force extended out 100 miles (160 km) in the northeastern quadrant of Bebinca’s circulation. Winds to tropical storm force only extended out 25 miles (40 km) in the other parts of Tropical Storm Bebinca.

Tropical Storm Bebinca will move through an environment favorable for intensification during the next 24 hours. Bebinca will move over water where the Sea Surface Temperatures are near 30°C. It will move under the western part of an upper level ridge over the Western North Pacific Ocean. The upper level ridge will produce southerly winds that will blow toward the top of Bebinca’s circulation. Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification. Tropical Storm Bebinca will intensify during the next 24 hours. Bebinca is likely to strengthen to a typhoon later this week.

Tropical Storm Bebinca will move around the southwestern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Bebinca toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Bebinca will move west of the Marianas. Bebinca could approach the Ryukyu Islands by the end of the week.

Typhoon Bolaven Rapidly Intensifies to Equivalent of Cat. 5 Hurricane

Typhoon Bolaven rapidly intensified to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale on Tuesday evening. At 11:00 p.m. EDT on Tuesday the center of Typhoon Bolaven was located at latitude 17.5°N and longitude 143.8°E which put it about 245 miles (390 km) north-northwest of Guam. Bolaven was moving toward the north-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 185 m.p.h. (295 km/h). The minimum surface pressure was 920 mb.

Typhoon Warnings were in effect for Rota, Tinian and Saipan. Tropical Storm Warnings were in effect for Agrihan, Pagan and Alamagan.

Typhoon Bolaven rapidly intensified to the equivalent of a Category 5 hurricane west of the Marianas on Tuesday evening. A small circular eye with a diameter of 14 miles (22 km) was at the center of Bolaven’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Bolaven. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Bolaven was very symmetrical. Winds to typhoon force extended out 25 miles (40 km) from the center of Bolaven’s circulation. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Bolaven was 35.0. The Hurricane Size Index (HSI) was 11.5 and the Hurricane Wind Intensity Size Index (HWISI) was 46.5.

Typhoon Bolaven will move through an environment favorable for intensification during the next 24 hours. Bolaven will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Bolaven could continue to intensify during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then concentric eyewalls could form. If concentric eyewalls form, then an eyewall replacement cycle could cause Typhoon Bolaven to weaken.

Typhoon Bolaven will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Bolaven toward the north-northwest during the next 24 hours. On its anticipated track, the Typhoon Bolaven will stay west of the Marianas during the next 24 hours.

Typhoon Bolaven Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Bolaven rapidly intensified to the equivalent of a major hurricane over the Western North Pacific Ocean north of Guam on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Typhoon Bolaven was located at latitude 16.4°N and longitude 144.3°E which put it about 100 miles (160 km) northwest of Tinian. Bolaven was moving toward the north-northwest at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h). The minimum surface pressure was 959 mb.

A Typhoon Warning was in effect for Rota, Tinian and Saipan. A Typhoon Watch was in effect for Guam. A Tropical Storm Warning was in effect for Guam.

Typhoon Bolaven brought strong winds and heavy rain to Guam, Rota, Tinian and Saipan. The center of Bolaven passed between Rota and Tinian and the strongest winds likely occurred in those places. A weather station in Saipan reported a sustained wind speed of 49 m.p.h. (79 km/h) and a wind gust of 68 m.p.h. (110 km/h). A weather station at Guam International Airport reported a sustained wind speed of 32 m.p.h. (52 km/h) and a wind gust of 46 m.p.h. (74 km/h). That weather station also measured 4.54 inches (115.3 mm) of rain.

Typhoon Bolaven began to intensify rapidly as it moved west of the Marianas. A small circular eye with a diameter of 14 miles (22 km) developed at the center of Bolaven’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Bolaven. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The size of the circulation around Typhoon Bolaven increased when it intensified on Tuesday. Winds to typhoon force extended out 25 miles (40 km) from the center of Bolaven’s circulation. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Bolaven was 20.6. The Hurricane Size Index (HSI) was 11.5 and the Hurricane Wind Intensity Size Index (HWISI) was 32.1.

Typhoon Bolaven will move through an environment favorable for intensification during the next 24 hours. Bolaven will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Bolaven will intensify during the next 24 hours. Bolaven could intensify rapidly at times. Typhoon Bolaven could strengthen to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.

Bolaven Strengthens to a Typhoon East of Guam

Former Tropical Storm Bolaven strengthened to a typhoon east of Guam on Monday night. At 11:00 p.m. EDT on Monday the center of Typhoon Bolaven was located at latitude 14.0°N and longitude 146.0°E which put it about 110 miles (175 km) east of Guam. Bolaven was moving toward the northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 990 mb.

A Typhoon Warning was in effect for Rota, Tinian and Saipan. A Typhoon Watch was in effect for Guam. A Tropical Storm Warning was in effect for Guam.

Former Tropical Storm Bolaven strengthened to a typhoon as it neared the Marianas on Monday night. A circular eye formed at the center of Bolaven’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Bolaven. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The size of the circulation around Bolaven increased when it intensified on Monday. Winds to typhoon force extended out 35 miles (55 km) from the center of Bolaven’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation.

Typhoon Bolaven will move around the southwestern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Bolaven toward the northwest during the next 24 hours. On its anticipated track, the center Typhoon Bolaven will pass near Rota in a few hours.

Typhoon Bolaven will bring strong winds and heavy rain to Rota, Tinian and Saipan. The strongest winds are likely to occur in Rota and Tinian. Bolaven will also produce gusty winds and heavy rain in Guam. The strong winds will be capable of causing damage and electricity outages are likely. Heavy rain will cause flash floods in some locations.

Tropical Storm Bolaven Moves Toward the Marianas

Tropical Storm Bolaven moved toward the Marianas on Sunday night. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Bolaven was located at latitude 11.1°N and longitude 149.9°E which put it about 410 miles (660 km) east-southeast of Guam. Bolaven was moving toward the west-northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h). The minimum surface pressure was 992 mb.

A Typhoon Watch was in effect for Guam, Rota, Tinian and Saipan. A Tropical Storm Warning was also in effect for Guam.

Tropical Storm Bolaven strengthened on Sunday. The inner end of a rainband wrapped around the center of Bolaven’s circulation. Bands of showers and thunderstorms revolved around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 70 miles (100 km) from the center of Bolaven.

Tropical Storm Bolaven will move through an environment favorable for intensification during the next 24 hours. Bolaven will move over water where the Sea Surface Temperatures are near 30°C. It will move under the southern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Bolaven’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Tropical Storm Bolaven is likely to intensify to a typhoon during the next 24 hours.

Tropical Storm Bolaven will move around the southwestern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Bolaven toward the northwest during the next 24 hours. On its anticipated track Tropical Storm Bolaven will move closer to the Marianas. Bolaven could reach the Marianas in less than 36 hours. Bolaven will very likely be a typhoon when it reaches the Marianas.

Elsewhere over the Western North Pacific Ocean, former Typhoon Koinu made landfall on the coast of China west of Hong Kong on Sunday. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Koinu was located at latitude 21.5°N and longitude 112.9°E which put it about 75 miles (120 km) west-southeast of Hong Kong. Koinu was moving toward the west at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h). The minimum surface pressure was 988 mb.

Typhoon Koinu Lingers Near Hong Kong

Typhoon Koinu lingered over the Western North Pacific Ocean near Hong Kong on Saturday. At 11:00 p.m. EDT on Saturday the center of Typhoon Koinu was located at latitude 21.4°N and longitude 114.4°E which put it about 65 miles (105 km) south-southeast of Hong Kong. Koinu was moving toward the west-northwest at 4 m.p.h. (6 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 968 mb.

Typhoon Koinu weakened gradually on Saturday as it lingered near Hong Kong. Since Koinu moved very slowly, the strong winds in the lower atmosphere mixed cooler water to the surface of the ocean. Koinu was unable to extract as much energy from the cooler water and the typhoon weakened. Thunderstorms in Typhoon Koinu did not rise quite as high into the atmosphere.

Even though Typhoon Koinu weakened on Saturday, it still exhibited a well organized circulation. A very small eye was present at the center of Koinu’s circulation. The inner end of a rainband wrapped around the existing eye and eyewall, and concentric eyewalls could be developing. Bands of showers and thunderstorms revolved around the small core of Typhoon Koinu. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The size of the circulation around Typhoon Koinu decreased as Koinu gradually weakened. Winds to typhoon force extended out 25 miles (40 km) from the center of Koinu’s circulation. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Koinu was 16.5. The Hurricane Size Index (HSI) was 8.6. and the Hurricane Wind Intensity Size Index (HWISI) was 25.1.

Typhoon Koinu will move through an environment somewhat unfavorable for intensification during the next 24 hours. Koinu will move over water where the Sea Surface Temperatures are near 27°C. It will move under axis of an upper level ridge over China. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. However, strong winds in the lower atmosphere will continue to mix cooler water to the surface of the ocean. In addition, the circulation around the northern side of Typhoon Koinu could draw in some drier air from China. Typhoon Koinu is likely to continue to weaken gradually during the next 24 hours due to the mix of cooler water to the surface of the ocean.

Typhoon Koinu will move will move around the southern part of a high pressure system over eastern Asia. The high pressure system will steer Koinu slowly toward the west during the next 24 hours. On its anticipated track the center Typhoon Koinu will move south of Hong Kong on Sunday.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 15W strengthened to Tropical Storm Bolaven east-southeast of Guam. At 11:00 p.m. EDT on Saturday the center of Tropical Storm Bolaven was located at latitude 9.6°N and longitude 152.9°E which put it about 630 miles (1020 km) east-southeast of Guam. Bolaven was moving toward the west-northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1000 mb. Typhoon Watches were in effect for Guam, Rota, Tinian and Saipan.

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.

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.

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