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Typhoon Nyatoh Brings Wind and Rain to Iwo To

Typhoon Nyatoh brought wind and rain to Iwo To on Friday. At 10:00 a.m. EST on Friday the center of Typhoon Nyatoh was located at latitude 24.3°N and longitude 142.9°E which put it about 80 miles (130 km) southeast of Iwo To. Nyatoh was moving toward the northeast at 24 m.p.h. (39 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h). The minimum surface pressure was 947 mb.

Bands in the northwestern side of Typhoon Nyatoh brought strong winds and heavy rain to Iwo To on Friday. The core of Nyatoh’s circulation where the strongest winds were occurring passed to the southeast of Iwo To. An upper level trough over Japan was producing strong southwesterly winds that were blowing toward the top of Typhoon Nyatoh’s circulation. Those winds caused strong vertical wind shear and the shear started to weaken Nyatoh when it approached Iwo To. A circular eye was still present at the center of Typhoon Nyatoh, but the distribution of thunderstorms was asymmetrical. The strongest thunderstorms were occurring around the eye and in bands in the northern half of Nyatoh. Bands in the southern half of the typhoon consisted primarily of showers and lower clouds.

Even though Typhoon Nyatoh was weakening, it was still the equivalent of a major hurricane. Winds to typhoon force extended out 60 miles (95 km) from the center of Nyatoh. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Nyatoh was 23.6. The Hurricane Size Index (HSI) was 22.2 and the Hurricane Wind Intensity Size Index (HWISI) was 45.8.

The upper level trough over Japan will steer Typhoon Nyatoh quickly toward the northeast during the next 24 hours. On its anticipated track Nyatoh will move away from Iwo To and the weather conditions should improve. Typhoon Nyatoh will move through an environment that will be unfavorable for a typhoon. Nyatoh will move over water where the Sea Surface Temperatures are near 24.5˚C. The upper level trough will continue to produce strong vertical wind shear. A surface high pressure system over eastern Asia will transport drier air toward the western side of Nyatoh’s circulation. Cooler water, strong vertical wind shear, and drier air will cause Typhoon Nyatoh to weaken rapidly during the next 24 hours.

Typhoon Nyatoh Strengthens to Equivalent of a Major Hurricane

Typhoon Nyatoh strengthened to the equivalent of a major hurricane over the Western North Pacific Ocean southwest of Iwo To on Thursday. At 10:00 a.m. EST on Thursday the center of Typhoon Nyatoh was located at latitude 18.7°N and longitude 137.1°E which put it about 540 miles (875 km) southwest of Iwo To. Nyatoh was moving toward the northeast at 15 m.p.h. (24 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 955 mb.

Typhoon Nyatoh rapidly intensified to the equivalent of a major hurricane on Thursday. A circular eye with a diameter of 35 miles (55 km) formed at the center of Nyatoh. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Nyatoh. Storms near the core generated strong upper level divergence that pumped mass away to the northeast of the typhoon.

The circulation around Typhoon Nyatoh increased in size on Thursday. Winds to typhoon force extended out 65 miles (105 km) from the center of Nyatoh. Winds to tropical storm force extended out 220 miles (355 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Nyatoh was 20.6. The Hurricane Size Index (HSI) was 22.1 and the Hurricane Wind Intensity Size Index (HWISI) was 42.7.

Typhoon Nyatoh will move through an environment that will become unfavorable for intensification during the next 24 hours. Nyatoh will move over water where the Sea Surface Temperatures are near 28˚C. An upper level trough near Japan will produce southwesterly winds that will blow toward the top of Nyatoh’s circulation. Those winds will cause the vertical wind shear to increase during the next 24 hours. Clockwise flow around a surface high pressure system centered over eastern Asia will transport drier air toward the northwestern part of Nyatoh’s circulation. The drier air will begin to be pulled into the northwestern part of Typhoon Nyatoh’s circulation during the next 24 hours. The combination of more vertical wind shear and drier air will cause Typhoon Nyatoh to start to weaken.

The upper level trough near Japan will steer Typhoon Nyatoh toward the northeast during the next 24 hours. On its anticipated track Typhoon Nyatoh could approach Iwo To on Friday. Although Nyatoh will weaken, it will bring strong winds and locally heavy rain to Iwo To.

Typhoon Malou Brings Strong Winds, Rain to Ogasawara Islands

Typhoon Malou brought strong winds and heavy rain to the Ogasawara Islands on Thursday morning. At 5:00 a.m. EDT on Thursday the center of Typhoon Malou was located at latitude 25.6°N and longitude 141.2°E which put it about 15 miles (25 km) east of Iwo To. Malou was moving toward the north-northeast at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 100 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 967 mb.

The strong inner core of Typhoon Malou passed directly over Iwo To on Thursday morning. An eye with a diameter of 35 miles (55 km) was at the center of Malou. The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms. Winds to typhoon force extended out 70 miles (110 km) from the center of Malou. Winds to tropical storm force extended out 175 miles (280 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Malou was 16.5. The Hurricane Size Index (HSI) was 20.6 and the Hurricane Wind Intensity Size Index (HWISI) was 37.1.

An upper level trough near Japan will steer Typhoon Malou toward the northeast during the next several days. On its anticipated track Malou will move away from the Ogasawara Islands. Typhoon Malou will pass well to the southeast of the larger islands of Japan.

Typhoon Malou will move into an environment unfavorable for tropical cyclones during the next few days. Malou will move over water where the Sea Surface Temperatures are cooler. The upper level trough near Japan will produce stronger southwesterly winds that will blow toward the top of Malou’s circulation. The vertical wind shear will increase as the upper level winds get stronger. The combination of cooler water and stronger vertical wind shear will cause Typhoon Malou to weaken. The cooler water and stronger shear will also cause Malou to make a transition to an extratropical cyclone during the next few days.

Typhoon Malou Nears Iwo To

Typhoon Malou neared Iwo To on Wednesday night. At 11:00 p.m. EDT on Wednesday the center of Typhoon Malou was located at latitude 24.2°N and longitude 141.3°E which put it about 100 miles (160 km) south-southwest of Iwo To. Malou was moving toward the north-northeast at 14 m.p.h. (22km/h). The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 970 mb.

Typhoon Malou strengthened as it moved closer to Iwo To on Wednesday night. A very large eye with a diameter of 90 miles (145 km) was at the center of Malou. Several smaller counterclockwise circulations were rotating within the eye. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the large core of Typhoon Malou. Storms near the core generated upper level divergence that pumped mass away to the northeast of the typhoon.

The size of Typhoon Malou’s circulation increased on Wednesday. Winds to typhoon force extended out 60 miles (95 km) from the center of Malou. Winds to tropical storm force extended out 175 miles (280 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Malou was 13.9. The Hurricane Size Index (HSI) was 14.6 and the Hurricane Wind Intensity Size Index (HWISI) was 28.5.

Typhoon Malou will move through an environment favorable for intensification during the next 18 hours. Malou will move over water where the Sea Surface Temperatures are near 28˚C. An upper level trough near Japan will produce southwesterly winds that will blow toward the top of Malou’s circulation. However, the winds in the lower levels of the atmosphere will also blow from the southwest and so there will not be a lot of vertical wind shear. Typhoon Malou is could strengthen during the next 18 hours. The upper level winds will get stronger on Friday and the vertical wind shear will increase. Malou is likely to weaken and to begin a transition to an extratropical cyclone when the wind shear increases.

An upper level trough over Japan will steer Typhoon Malou toward the north-northeast during the next 24 hours. On its anticipated track Typhoon Malou could make a direct hit on Iwo To in a few hours. Typhoon Malou will bring strong winds and heavy rain to Iwo To. The eyewall with the strongest winds is likely to pass over Iwo To. The wind could blow at tropical storm force or greater for several hours. Malou will be capable of causing serious damage on Iwo To. In addition, heavy rain could also cause flash floods.

Hurricane Sam Passes East of Bermuda

Hurricane Sam passed east of Bermuda on Saturday morning. At 11:00 a.m. EDT on Saturday the center of Hurricane Sam was located at latitude 33.9°N and longitude 59.3°W which put it about 335 miles (540 km) east-northeast of Bermuda. Sam was moving toward the northeast at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h). The minimum surface pressure was 945 mb.

Hurricane Sam was still a powerful hurricane when it passed east of Bermuda on Saturday morning. Sam was rated at Category 4 on the Saffir-Simpson Scale. A circular eye with a diameter of 30 miles (50 km) was present at the center of Hurricane Sam. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving round the core of Sam’s circulation. Storms near the core generated strong upper level divergence that pumped mass away to the north of the hurricane.

The size of the circulation around Hurricane Sam continued to increase in size as it moved farther to the north. Winds to hurricane force extended out 65 miles (10 km) from the center of Sam. Winds to tropical storm force extended out 240 miles (390 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Sam was 25.1. The Hurricane Size Index (HSI) was 20.6 and the Hurricane Wind Intensity Size Index (HWISI) was 45.7.

Hurricane Sam will move through an environment capable of maintaining a major hurricane during the next 12 hours. Sam will move over water where the Sea Surface Temperatures are near 27˚C. It will move through a region where the upper level winds are weak during the next 12 hours. An upper level trough east of the U.S. will produce southwesterly winds that will start to affect Hurricane Sam on Sunday. Those winds will blow toward the top of Sam’s circulation and they will cause more vertical wind shear. Hurricane Sam will also move over cooler water on Sunday. The wind shear and cooler water will cause Hurricane Sam to weaken as it begins a transition to a strong extratropical cyclone.

The upper level trough east of the U.S. will steer Hurricane Sam toward the northeast later during the next several days. On its anticipated track Hurricane Sam will pass southeast of Newfoundland on Monday. Sam could be a powerful extratropical cyclone southeast of Greenland by early next week.

Elsewhere over the Atlantic Ocean, Tropical Storm Victor weakened west of the Cabo Verde Islands. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Victor was located at latitude 13.1°N and longitude 37.2°W which put it about 905 miles (1455 km) west of the Cabo Verde Islands. Victor was moving toward the northwest at 12 m.p.h. (19 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 1005 mb.

Bermuda Issues Tropical Storm Warning Because of Hurricane Sam

Bermuda issued a Tropical Storm Warning because of the potential effects of Hurricane Sam. At 5:00 p.m. EDT on Thursday the center of Hurricane Sam was located at latitude 23.6°N and longitude 60.9°W which put it about 645 miles (1040 km) south-southeast of Bermuda. Sam was moving toward the northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 170 m.p.h. (280 km/h). The minimum surface pressure was 938 mb.

A Tropical Storm Warning was in effect for Bermuda.

Hurricane Sam continued to be a powerful hurricane on Thursday. Sam was rated at Category 4 on the Saffir-Simpson Scale. A circular eye with a diameter of 28 miles (44 km) was present at the center of Hurricane Sam. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving round the core of Sam’s circulation. Storms near the core generated strong upper level divergence that pumped mass away from the hurricane.

The size of the circulation around Hurricane Sam was increasing in size as it moved farther to the north. Winds to hurricane force extended out 60 miles (95 km) from the center of Sam. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Sam was 29.8. The Hurricane Size Index (HSI) was 17.5 and the Hurricane Wind Intensity Size Index (HWISI) was 47.3.

Hurricane Sam will move through an environment capable of maintaining a major hurricane during the next 36 hours. Sam will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level winds are weak during the next 24 hours. An upper level trough east of the U.S. will produce southwesterly winds that will start to affect Hurricane Sam later on Friday. Those winds will blow toward the top of Sam’s circulation and they will cause more vertical wind shear. The wind shear will cause Hurricane Sam to start to weaken.

Hurricane Sam will move around the western end of a high pressure system over the Atlantic Ocean during the next 24 hours. The high will steer Sam toward the north during that time period. The upper level trough east of the U.S. will start to steer Hurricane Sam toward the northeast later on Friday. On its anticipated track Hurricane Sam will pass east of Bermuda on Friday night. The western fringes of Sam could bring gusty winds and locally heavy rain to Bermuda, which is why the Tropical Storm Warning was issued.

Elsewhere over the Atlantic Ocean, Tropical Storm Victor strengthened a little southwest of the Cabo Verde Islands. At 5:00 p.m. EDT on Thursday the center of Tropical Storm Victor was located at latitude 9.9°N and longitude 30.0°W which put it about 585 miles (940 km) southwest of the Cabo Verde Islands. Victor was moving toward the west-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1003 mb.

Typhoon Mindulle Passes South of Tokyo

Typhoon Mindulle passed south of Tokyo on Thursday. At 5:00 p.m. EDT on Thursday the center of Typhoon Mindulle was located at latitude 31.1°N and longitude 140.0°E which put it about 340 miles (545 km) south of Tokyo, Japan. Mindulle was moving toward the northeast at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 969 mb.

The core of Typhoon Mindulle passed well to the south of Tokyo on Thursday. However, the circulation around Typhoon Mindulle was so large, that bands of showers and thunderstorms on the northern periphery of Mindulle were bringing gusty winds and rain to parts of Honshu. Winds to typhoon force extended out 130 miles (210 km) on the eastern side of Typhoon Mindulle. Winds to typhoon force extended out 75 miles in the western half of Mindulle. Winds to tropical storm force extended out 310 miles (500 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Mindulle was 13.9. The Hurricane Size Index (HSI) was 37.6 and the Hurricane Wind intensity Size Index (HWISI) was 51.5.

Typhoon Mindulle weakened as it moved over cooler water and into a region where westerly winds in the upper levels caused more vertical wind shear. A larger eye was present at the center of Mindulle, but breaks were developing in the ring of thunderstorms around the eye. The upper level westerly winds in the middle latitudes were beginning to affect the structure of Typhoon Mindulle. Those winds were blowing toward the top of Mindulle’s circulation and they were causing increasing vertical wind shear. The strongest thunderstorms were occurring in bands north and east of the center of the typhoon. Bands south and west of the center consisted primarily of showers and lower clouds. The combination of cooler water and more wind shear was causing Typhoon Mindulle to start a transition to an extratropical cyclone.

The westerly winds in the upper levels will steer Typhoon Mindulle quickly toward the northeast during the next 48 hours. On its anticipated track the core of Mindulle will pass well to the east of Honshu and Hokkaido. Bands on the northern side of Typhoon Mindulle could bring gusty winds and heavy rain to coastal parts of northern Honshu and eastern Hokkaido. Big waves will affect shipping southeast of Japan. Mindulle will weaken gradually during the next 48 hours while it makes a transition to an extratropical cyclone.

Typhoon Mindulle Strengthens Back to Equivalent of a Major Hurricane

Typhoon Mindulle strengthened back to the equivalent of a major hurricane west-southwest of Iwo To on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Typhoon Mindulle was located at latitude 23.0°N and longitude 135.6°E which put it about 390 miles (630 km) west-southwest of Iwo To. Mindulle was moving toward the north at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 950 mb.

Typhoon Mindulle strengthened back to the equivalent of a major hurricane after it completed several Eyewall Replacement Cycles. A large circular eye with a diameter of 45 miles (75 km) was present at the center of Typhoon Mindulle. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Mindulle. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Mindulle grew even larger after it completed the Eyewall Replacement Cycles. Winds to typhoon force extended out 70 miles (110 km) from the center of Mindulle. Winds to tropical storm force extended out 235 miles (380 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Mindulle was 22.1. The Hurricane size Index (HSI) was 27.4 and the Hurricane Wind Intensity Size Index (HWISI) was 49.5.

Typhoon Mindulle will move through an environment capable of sustaining a powerful typhoon during the next 36 hours. Mindulle will move over water where the Sea Surface Temperatures are near 29˚C. It will move into a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Mindulle could strengthen gradually during the next 36 hours.

Typhoon Mindulle will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next 48 hours. The high pressure system will steer Mindulle toward the north during the next 24 hours. Typhoon Mindulle will start to move toward the northeast after it moves around the western end of the high. On its anticipated track Typhoon Mindulle will pass west of Iwo To during the next 24 hours. Mindulle cold be south of Tokyo in 48 hours.

Hurricane Sam Strengthens Back to Cat. 4

Hurricane Sam strengthened back to Category 4 on the Saffir-Simpson Scale on Tuesday morning. At 11:00 a.m. EDT on Tuesday the center of Hurricane Sam was located at latitude 17.5°N and longitude 54.3°W which put it about 580 miles (935 km) east of the Northern Leeward Islands. Sam moving toward the northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 155 m.p.h. (250 km/h). The minimum surface pressure was 954 mb.

Hurricane Sam strengthened back to Category 4 after completing several Eyewall Replacement Cycles. The Eyewall Replacement Cycles also resulted in an increase in the size of Hurricane Sam. A larger circular eye with a diameter of 40 miles (65 km) was present at the center of Sam. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Sam. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Sam was larger after the completion of the Eyewall Replacement Cycles. Winds to hurricane force extended out 40 miles (65 km) from the center of Sam. Winds to tropical storm force extended out 140 miles (225 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Sam was 25.1. The Hurricane Size Index (HSI) was 14.2 and the Hurricane Wind Intensity Size Index (HWISI) was 39.3.

Hurricane Sam will move through an environment capable of sustaining a major hurricane during the next 48 hours. Sam will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Sam could strengthen in the favorable environment.

Hurricane Sam will move around the southwestern part of a subtropical high pressure system over the Atlantic Ocean. The high will steer Sam toward the northwest during the next 48 hours. On its anticipated track Hurricane Sam could pass northeast of the Northern Leeward Islands on Thursday. Sam could be southeast of Bermuda by Friday.

Hurricane Sam Peaks Just Shy of Cat. 5

Hurricane Sam peaked just shy of Category 5 on the Saffir-Simpson Scale on Sunday. At 11:00 p.m. EDT on Sunday the center of Hurricane Sam was located at latitude 14.7°N and longitude 50.8°W which put it about 850 miles (1365 km) east-southeast of the Northern Leeward Islands. Sam moving toward the northwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 170 m.p.h. (280 km/h). The minimum surface pressure was 943 mb.

The National Hurricane Center indicated that the maximum sustained wind speed in Hurricane Sam may have peaked at 155 m.p.h. (250 km/h) on Sunday afternoon before an Eyewall Replacement Cycle halted intensification. The inner end of a rainband wrapped around the existing small eye and eyewall at the center of Hurricane Sam. There were two concentric eyewalls for a period of time and then the inner eyewall began to dissipate. Low level convergence became primarily concentrated on the outer eyewall. The outer eyewall had a diameter of 16 miles (26 km). The western side of the outer eyewall was weaker and the rainbands on the western side of Hurricane Sam were also weaker.

The size of the circulation around Hurricane Sam only increased slightly as a result of the Eyewall Replaement Cycle. Winds to hurricane force extended out 30 miles (50 km) from the center of Sam. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) was 29.9. The Hurricane Size Index (HSI) was 9.8 and the Hurricane Wind Intensity Size Index (HWISI) was 39.7.

Hurricane Sam will move through an environment capable of sustaining a major hurricane during the next 48 hours. Sam will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. The current Eyewall Replacement Cycle will cause Hurricane Sam to weaken until the outer eyewall becomes full developed. Additional Eyewall Replacement Cycles could occur which would cause fluctuations in the intensity of Hurricane Sam.

Hurricane Sam will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high will steer Sam toward the northwest during the next 48 hours. On its anticipated track Hurricane Sam could be east of the Northern Leeward Islands by Wednesday.