Monthly Archives: September 2023

Hurricane Lee Moves South of Bermuda

Hurricane Lee moved south of Bermuda on Monday. At 11:00 p.m. EDT on Monday the center of Hurricane Lee was located at latitude 23.9°N and longitude 64.8°W which put it about 580 miles (935 km) south of Bermuda. Lee was moving toward the west-northwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (215 km/h). The minimum surface pressure was 948 mb.

Hurricane Lee went through another eyewall replacement cycle on Monday. The inner end of a rainband wrapped around the existing eye and eyewall early on Monday. Two concentric eyewalls were present at the core of Lee’s circulation during much of Monday. The inner eyewall weakened throughout the day, but a portion of the inner eyewall was still present on microwave satellite images on Monday evening. Low level convergence became concentrated into the outer eyewall and the outer eyewall began to contract around the center of Hurricane Lee. Bands of showers and thunderstorms revolved around the concentric eyewalls. Storms near the core of Lee’s circulation generated upper level divergence that pumped mass away from the hurricane.

The eyewall replacement cycle caused some fluctuations in the size and intensity of Hurricane Lee on Monday. Winds to hurricane force extended out 80 miles (130 km) from the center of Lee’s circulation. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) was 20.6. The Hurricane Size Index (HSI) was 26.4 and the Hurricane Wind Intensity Size Index (HWISI) was 47.0. Hurricane Lee was similar in size and intensity to Hurricane Irma when Irma hit Southwest Florida in 2017.

Hurricane Lee will move through an environment that will be favorable for intensification during the next 24 hours. Lee 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. If the inner eyewall dissipates completely, then Hurricane Lee could intensify on Tuesday.

Hurricane Lee will move around the southwestern part of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the northwest during the next 24 hours. On its anticipated track, Hurricane Lee will be far to the south of Bermuda on Tuesday.

Elsewhere over the Atlantic Ocean, former Tropical Storm Margot intensified to a hurricane over the Central Atlantic. At 11:00 p.m. EDT on Monday the center of Hurricane Margot was located at latitude 28.0°N and longitude 39.6°W which put it about 1295 miles (2085 km) northwest of the Cabo Verde Islands. Margot was moving toward the north 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 95 m.p.h. (150 km/h). The minimum surface pressure was 984 mb.

Hurricane Lee Moves Northeast of Puerto Rico

Hurricane Lee moved northeast of Puerto Rico on Sunday night. At 11:00 p.m. EDT on Sunday the center of Hurricane Lee was located at latitude 22.6°N and longitude 62.2°W which put it about 400 miles (645 km) northeast of the San Juan, Puerto Rico. Lee was moving toward the northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (220 km/h). The minimum surface pressure was 950 mb.

Hurricane Lee intensified on Sunday after it completed an eyewall replacement cycle. The inner eyewall dissipated on Sunday morning. The outer eyewall surrounded an eye with a diameter of 30 miles (50 km) developed at the center of Lee’s circulation. The strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms revolved around the core of Hurricane Lee. Storms near the core of Lee’s circulation generated upper level divergence that pumped mass away from the hurricane.

Hurricane Lee was turning into a large and powerful hurricane on Sunday night. Winds to hurricane force extended out 75 miles (120 km) from the center of Lee’s circulation. Winds to tropical storm force extended out 175 miles (280 km) from the center of circulation. The Hurricane Intensity Index (HII) was 22.1. The Hurricane Size Index (HSI) was 22.6 and the Hurricane Wind Intensity Size Index (HWISI) was 44.7.

Hurricane Lee will move through an environment that will be favorable for intensification during the next 24 hours. Lee 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. Hurricane Lee could intensify to Category 4 on the Saffir-Simpson Scale on Monday.

Hurricane Lee will move around the southwestern part of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the northwest during the next 24 hours. On its anticipated track, Hurricane Lee will pass far to the north of the Puerto Rico on Tuesday.

Elsewhere over the Atlantic Ocean, Tropical Storm Margot continued to intensify gradually over the Central Atlantic Ocean. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Margot was located at latitude 24.6°N and longitude 39.9°W which put it about 1185 miles (1910 km) west-northwest of the Cabo Verde Islands. Margot was moving toward the north at 8 m.p.h. (13 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 996 mb.

Hurricane Lee Moves Northeast of the Leeward Islands

Hurricane Lee moved northeast of the Leeward Islands on Saturday night. At 11:00 p.m. EDT on Saturday the center of Hurricane Lee was located at latitude 21.0°N and longitude 59.9°W which put it about 285 miles (455 km) northeast of the Northern Leeward Islands. Lee was moving toward the west-northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 962 mb.

Hurricane Lee was in the middle of an eyewall replacement cycle on Saturday evening. A small eye was at the center of Lee’s circulation. The small eye was surrounded by a tight ring of thunderstorms. The strongest winds were occurring in that ring of storms. A second eyewall surrounded the small eye and inner eyewall. The eyewall replacement cycle and some vertical wind shear caused Hurricane Lee to weaken on Saturday. Bands of showers and thunderstorms revolved around the two concentric eyewalls. Storms near the center of Lee’s circulation generated upper level divergence that pumped mass away from the hurricane.

The eyewall replacement cycle caused the size of Hurricane Lee’s circulation to increase. Winds to hurricane force extended out 35 miles (55 km) from the center of Lee’s circulation. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) was 17.8. The Hurricane Size Index (HSI) was 13.6 and the Hurricane Wind Intensity Size Index (HWISI) was 31.4.

Hurricane Lee will move through an environment that will become more favorable for intensification during the next 24 hours. Lee 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 weaker and there will be less vertical wind shear. Hurricane Lee is likely to weaken on Sunday until the eyewall replacement cycle is completed, even though Lee will move into a more favorable environment. After the inner eyewall dissipates, low level convergence will increase into the larger outer eyewall. When the low level convergence becomes more concentrated in the outer eyewall, then Hurricane Lee could start to intensify again.

Hurricane Lee will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the west-northwest during the next 24 hours. On its anticipated track, Hurricane Lee could be north of the Puerto Rico by early next week.

Elsewhere over the Atlantic Ocean, Tropical Storm Margot gradually intensified west-northwest of the Cabo Verde Islands. At 11:00 p.m. EDT on Saturday the center of Tropical Storm Margot was located at latitude 21.6°N and longitude 39.1°W which put it about 1060 miles (1705 km) west-northwest of the Cabo Verde Islands. Margot was moving toward the northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 1000 mb.

Jova Weakens to a Tropical Storm

Former Hurricane Jova weakened to a tropical storm over the Eastern North Pacific Ocean west of Baja California during Friday night. At 5:00 a.m. EDT on Saturday the center of Tropical Storm Jova was located at latitude 21.5°N and longitude 124.6°W which put it about 945 miles (1520 km) west of the southern tip of Baja California. Jova was moving toward the west-northwest at 13 m.p.h. (21 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 986 mb.

Former Category 5 Hurricane Jova weakened to a tropical storm over cooler water during Friday night. Even though Jova weakened to a tropical storm, its circulation was well organized. Tropical Storm Jova completed an eyewall replacement cycle as it moved over cooler water. The original inner eye and eyewall dissipated. The outer eyewall surrounded a clear area at the center of Jova’s circulation. Bands of showers and thunderstorms revolved around the center of Tropical Storm Jova. The thunderstorms did not rise as high in the atmosphere because of the cooler water at the surface of ocean. Winds to tropical storm force extended out 115 miles (185 km) from the center of Jova’s circulation.

Tropical Storm Jova will move through an environment unfavorable for intensification during the next 48 hours. Jova will move over water where the Sea Surface Temperatures are near 24°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Jova will continue to weaken gradually over cooler water, even though there will be little vertical wind shear. Jova could weaken to a tropical depression by the end of the weekend.

Tropical Storm Jova will move around the southern part of a high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Jova toward the west-northwest during the next 48 hours. On its anticipated track, Tropical Storm Jova will move farther away from Baja California.

Hurricane Lee Weakens East of the Northern Leeward Islands

Hurricane Lee weakened while it moved over the Atlantic Ocean east of the Northern Leeward Islands on Friday. At 11:00 p.m. EDT on Friday the center of Hurricane Lee was located at latitude 19.3°N and longitude 56.5°W which put it about 440 miles (705 km) east of the Northern Leeward Islands. Lee was moving toward the west-northwest at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (220 km/h). The minimum surface pressure was 963 mb.

An upper level trough near Puerto Rico produced strong southwesterly winds that blew toward the top of Hurricane Lee. Those winds caused moderate vertical wind shear. Those winds also inhibited the upper level divergence in the southern side of Hurricane Lee. Hurricane Lee was unable to pump away as much mass as was flowing into Lee in the lower levels of the atmosphere. More mass accumulated in the center of Hurricane Lee and the surface pressure rose quickly on Friday.

The inner core of Hurricane Lee was disrupted by the moderate vertical wind shear. The ring of thunderstorms surrounding the eye was broken south of the center of Lee’s circulation. Bands in the southwestern part of Hurricane Lee consisted primarily of showers and lower clouds. Most of the thunderstorms were occurring in bands in the northern half of Lee’s circulation. Thunderstorms in the northern side of Lee still generated upper level divergence that pumped mass away to the north of the hurricane.

The size of the circulation around Hurricane Lee increased on Friday. Winds to hurricane force extended out 30 miles (50 km) from the center of Lee’s circulation. Winds to tropical storm force extended out 175 miles (280 km) from the center of circulation. The Hurricane Intensity Index (HII) was 20.6. The Hurricane Size Index (HSI) was 12.4 and the Hurricane Wind Intensity Size Index (HWISI) was 33.0.

Hurricane Lee will move through an environment only marginally favorable for intensification during the next 24 hours. Lee will move over water where the Sea Surface Temperatures are near 29°C. However, the upper level trough near Puerto Rico will still continue to cause vertical wind shear on Saturday. Hurricane Lee could continue to weaken during the next 24 hours.

Hurricane Lee will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the west-northwest during the next 24 hours. On its anticipated track, Hurricane Lee could be northeast of the Northern Leeward Islands by Saturday night.

Elsewhere over the Atlantic Ocean, Tropical Storm Margot was moved farther away from the Cabo Verde Islands. At 11:00 p.m. EDT on Friday the center of Tropical Storm Margot was located at latitude 19.5°N and longitude 35.8°W which put it about 810 miles (1310 km) west-northwest of the Cabo Verde Islands. Margot was moving toward the west-northwest at 17 m.p.h. (28 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.

Hurricane Jova Weakens Southwest of Baja California

Hurricane Jova weakened over the Eastern North Pacific Ocean southwest of Baja California on Thursday. At 11:00 p.m. EDT on Thursday the center of Hurricane Jova was located at latitude 18.3°N and longitude 118.6°W which put it about 645 miles (1040 km) west-southwest of the southern tip of Baja California. Jova was moving toward the west-northwest at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 951 mb.

Hurricane Jova started an eyewall replacement cycle on Thursday. The inner end of a rainband wrapped around the original eye and eyewall. A larger outer eyewall surrounded the original eye and eyewall. The inner eyewall, which was where the strongest winds were, began to weaken after the outer eyewall developed. The inner eyewall was still evident on microwave satellite images on Thursday night. A larger clear area, sometimes called a moat, was between the inner eyewall and the outer eyewall. Bands of showers and thunderstorms were revolving around the two concentric eyewalls.

Hurricane Jova started to weaken as the eyewall replacement cycle progressed. Winds to hurricane force extended out 25 miles (40 km) from the center of Jova’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation. The Hurricane Intensity Index (HII) was 23.6. The Hurricane Size Index (HSI) was 10.4 and the Hurricane Wind Intensity Size Index (HWISI) was 34.0.

Hurricane Jova will move through an environment that will become unfavorable for intensification during the next 24 hours. Jova will move over water where the Sea Surface Temperatures are cooler than 26°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Jova will weaken during the next 24 hours as the inner eyewall dissipates. Jova will weaken more quickly when it moves over cooler water.

Hurricane Jova will move around the southern part of a high pressure system over northern Mexico and the Eastern North Pacific Ocean. The high pressure system will steer Jova toward the west-northwest during the next 24 hours. On its anticipated track, Hurricane Jova will move farther away from Baja California.

Hurricane Lee Rapidly Intensifies to Cat. 5

Hurricane Lee rapidly intensified to Category 5 on the Saffir-Simpson Scale over Atlantic Ocean east of the Northern Leeward Islands on Thursday. At 11:00 p.m. EDT on Thursday the center of Hurricane Lee was located at latitude 17.3°N and longitude 52.4°W which put it about 705 miles (1135 km) east of the Northern Leeward Islands. Lee was moving toward the west-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 190 m.p.h. (240 km/h). The minimum surface pressure was 928 mb.

A circular eye with a diameter of 17 miles (28 km) was at the center of Hurricane Lee. A ring of thunderstorms surrounded the eye and the strongest winds were occurring in the ring of storms. Bands of showers and thunderstorms were revolving around the core of Lee’s circulation. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the hurricane. The removal of large amounts of mass caused the surface pressure to decrease rapidly.

Hurricane Lee rapidly intensified to Category 5 on the Saffir-Simpson Scale on Thursday. Winds to hurricane force extended out 45 miles (75 km) from the center of Lee’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation. The Hurricane Intensity Index (HII) was 35.0. The Hurricane Size Index (HSI) was 13.4 and the Hurricane Wind Intensity Size Index (HWISI) was 48.4.

Hurricane Lee will move through an environment favorable for intensification during the next 24 hours. Lee will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Lee could continue to intensify during the next 24 hours.

Hurricane Lee will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the west-northwest during the next 36 hours. On its anticipated track, Hurricane Lee could be northeast of the Northern Leeward Islands by Friday night.

Elsewhere over the Atlantic Ocean, Tropical Storm Margot was spinning west-northwest of the Cabo Verde Islands. At 11:00 p.m. EDT on Thursday the center of Tropical Storm Margot was located at latitude 16.8°N and longitude 29.3°W which put it about 355 miles (570 km) west-northwest of the Cabo Verde Islands. Margot was moving toward the west-northwest at 16 m.p.h. (26 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 1004 mb.

Lee Rapidly Intensifies to a Major Hurricane

Hurricane Lee rapidly intensified to a major hurricane over Atlantic Ocean east of the Northern Leeward Islands on Thursday. At 5:00 p.m. EDT on Thursday the center of Hurricane Lee was located at latitude 16.9°N and longitude 51.3°W which put it about 780 miles (1260 km) east of the Northern Leeward Islands. Lee was moving toward the west-northwest at 15 m.p.h. (24 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 953 mb.

Hurricane Lee rapidly intensified to a major hurricane on Thursday. The inner end of rainband wrapped around the center of Lee’s circulation. An eye with a diameter of 23 miles (37 km) formed at the center of Hurricane Lee. A ring of thunderstorms surrounded the eye and the strongest winds were occurring in the ring of storms. Bands of showers and thunderstorms were revolving around the core of Lee’s circulation. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the hurricane. The removal of large amounts of mass caused the surface pressure to decrease rapidly.

Hurricane Lee rapidly intensified to Category 4 on the Saffir-Simpson Scale on Thursday. Winds to hurricane force extended out 30 miles (50 km) from the center of Lee’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation. The Hurricane Intensity Index (HII) was 25.1. The Hurricane Size Index (HSI) was 10.3 and the Hurricane Wind Intensity Size Index (HWISI) was 35.4.

Hurricane Lee will move through an environment favorable for intensification during the next 24 hours. Lee will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Lee will intensify during the next 24 hours. Lee could strengthen to Category 5 on Friday.

Hurricane Lee will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the west-northwest during the next 36 hours. On its anticipated track, Hurricane Lee could be northeast of the Northern Leeward Islands by Friday night.

Elsewhere over the Atlantic Ocean, Tropical Storm Margot developed west-northwest of the Cabo Verde Islands. At 5:00 p.m. EDT on Thursday the center of Tropical Storm Margot was located at latitude 16.8°N and longitude 28.3°W which put it about 290 miles (465 km) west-northwest of the Cabo Verde Islands. Margot was moving toward the west-northwest at 17 m.p.h. (28 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 1004 mb.

Hurricane Jova Rapidly Intensifies to Cat. 5

Hurricane Jova rapidly intensified to Category 5 on the Saffir-Simpson Scale over the Eastern North Pacific Ocean south of Baja California on Wednesday. At 11:00 p.m. EDT on Wednesday the center of Hurricane Jova was located at latitude 15.4°N and longitude 113.0°W which put it about 535 miles (865 km) south-southwest of the southern tip of Baja California. Jova was moving toward the west-northwest at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 190 m.p.h. (305 km/h). The minimum surface pressure was 929 mb.

Hurricane Jova intensified from a tropical depression to a Category 5 hurricane in 48 hours. A circular eye with a diameter of 12 miles (19 km) formed at the center of Jova’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 Hurricane Jova. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the hurricane. The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The size of the circulation around Hurricane Jova increased as Jova rapidly intensified. Winds to hurricane force extended out 30 miles (50 km) from the center of Jova’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) was 35.0. The Hurricane Size Index (HSI) was 9.0 and the Hurricane Wind Intensity Size Index (HWISI) was 44.0.

Hurricane Jova will move through an environment favorable for intensification during the next 12 hours. Jova will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Jova could continue to intensify during the next 12 hours. The inner end of a rainband appeared to be wrapping around the existing eye and eyewall in the core of Jova’s circulation. If concentric eyewalls form, then an eyewall replacement cycle will cause Hurricane Jova to weaken on Thursday. Jova will move over cooler water on Friday, which will also cause it to weaken.

Hurricane Jova will move around the southern part of a high pressure system over northern Mexico and the Eastern North Pacific Ocean. The high pressure system will steer Jova toward the west-northwest during the next 24 hours. On its anticipated track, Hurricane Jova will stay far to the southwest of Baja California.

Tropical Storm Yun-yeung Moves Toward Honshu

Tropical Storm Yun-Yeung moved toward Honshu on Wednesday. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Yun-yeung was located at latitude 30.2°N and longitude 136.7°E which put it about 430 miles (695 km) south-southwest of Tokyo, Japan. Yun-yeung was moving toward the north-northeast at 15 m.p.h. (24 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 994 mb.

Tropical Storm Yun-yeung consisted primarily of a low level circulation on Wednesday night. The bands revolving around the center of Yun-yeung’s circulation contained primarily showers and lower clouds. A strong upper level trough northwest of Japan produced strong southwesterly winds that blew across the top of Tropical Storm Yun-Yeung. Those winds caused strong vertical wind shear and the winds blew the upper part of Yun-Yeung’s circulation to the northeast of the circulation near the surface . There was a band of thunderstorms near the northern periphery of Tropical Storm Yun-yeung. Winds to tropical storm force extended out 100 miles (160 km) in the eastern side of Yun-Yeung’s circulation. The winds in the western side of Yun-yeung were blowing at less than tropical storm force.

Tropical Storm Yun-yeung will move through an environment unfavorable for intensification of a tropical storm during the next 36 hours. Yun-yeung will move over water where the Sea Surface Temperatures are near 28°C. However, the upper level trough northwest of Japan will continue to cause strong vertical wind shear. The strong vertical wind shear will prevent intensification of Tropical Storm Yun-yeung. Yun-yeung could get a little stronger, if it makes a transition to an extratropical cyclone.

Tropical Storm Yun-yeung will move around the northwestern part of high pressure system over the Western North Pacific. The high pressure system and the upper level trough northwest of Japan will steer Yun-yeung toward the northeast during the next 36 hours. On its anticipated track, Tropical Storm Yun-yeung will approach Tokyo in 36 hours.