Monthly Archives: September 2023

Jova Rapidly Intensifies to a Major Hurricane

Hurricane Jova rapidly intensified to a major hurricane over the Eastern North Pacific Ocean south of Baja California on Wednesday. At 5:00 p.m. EDT on Wednesday the center of Hurricane Jova was located at latitude 14.9°N and longitude 111.7°W which put it about 565 miles (910 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 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 Jova intensified very rapidly to a major hurricane on Wednesday. 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.

Hurricane Jova rapidly intensified to Category 4 on the Saffir-Simpson Scale. Winds to hurricane force extended out 25 miles (40 km) from the center of Jova’s circulation. Winds to tropical storm force extended out 130 miles (210 km) from the center of circulation. The Hurricane Intensity Index (HII) was 25.1. The Hurricane Size Index (HSI) was 7.4 and the Hurricane Wind Intensity Size Index (HWISI) was 32.5.

Hurricane Jova will move through an environment favorable for intensification during the next 24 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 will intensify during the next 24 hours. Jova could strengthen to Category 5 on the Saffir-Simpson Scale.

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.

Lee Intensifies to a Hurricane

Former Tropical Storm Lee intensified to a hurricane over the Atlantic Ocean east of the Northern Leeward Islands on Wednesday. At 5:00 p.m. EDT on Wednesday the center of Hurricane Lee was located at latitude 14.9°N and longitude 46.4°W which put it about 1130 miles (1815 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 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h). The minimum surface pressure was 991 mb.

Former Tropical Storm Lee rapidly intensified to a hurricane on Wednesday. The inner end of a rainband wrapped most of the way around the center of Lee’s circulation. The strongest winds were occurring in the inner end of the rainband. An eye was forming at the center of Hurricane Lee. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the hurricane. Winds to hurricane force extended out 20 miles (30 km) from the center of lee’s circulation. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation.

Hurricane Lee will move through an environment favorable for intensification during the next 48 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 48 hours. Lee could strengthen to a major hurricane 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, Tropical Storm Lee could be northeast of the Northern Leeward Islands by Friday night.

Jova Rapidly Intensifies to a Hurricane

Former Tropical Storm Jova rapidly intensified to a hurricane over the Eastern North Pacific Ocean south of Baja California during Tuesday night. At 5:00 a.m. EDT on Wednesday the center of Hurricane Jova was located at latitude 13.6°N and longitude 109.6°W which put it about 640 miles (1035 km) southeast of the southern tip of Baja California. Jova was moving toward the west-northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 979 mb.

The maximum sustained wind speed in former Tropical Storm Jova increased 45 m.p.h. (75 km/h) during the past 24 hours. The inner end of a rainband wrapped most of the way around the center of Hurricane Jova. The strongest winds were occurring in the inner end of the rainband. A small circular eye was starting to appear on microwave satellite images. Other bands of showers and thunderstorms were revolving around the core of Hurricane Jova. Storms near the core generated upper level divergence that pumped mass away from the hurricane. Winds to hurricane force extended out 15 miles (20 km) from the center of Jova’s circulation. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation.

Hurricane Jova will move through an environment favorable for intensification during the next 36 hours. Jova will move over water where the Sea Surface Temperatures are near 29°C. It will move under the southern part of an upper level ridge over Mexico and the Eastern North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Jova’s circulation. The winds in the lower levels of the atmosphere will also blow from the east and there will be little vertical wind shear. Hurricane Jova will intensify during the next 36 hours. Jova is likely to strengthen to a major hurricane by Wednesday.

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 36 hours. On its anticipated track, Hurricane Jova will stay far to the southwest of Baja California.

Tropical Storm Yun-yeung Forms South of Japan

Tropical Storm Yun-yeung formed over the Western North Pacific Ocean south of Japan on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Yun-yeung was located at latitude 26.2°N and longitude 133.6°E which put it about 810 miles (1305 km) south-southwest of Tokyo, Japan. Yun-yeung was moving toward the north 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 998 mb.

A low pressure system over the Western North Pacific Ocean strengthened on Tuesday and the Japan Meteorological Agency designated the system as Tropical Storm Yun-yeung. More thunderstorms developed near the center of Yun-yeung’s circulation on Tuesday evening, but the distribution of thunderstorms was asymmetrical. Most of the thunderstorms were occurring in bands in the southern half of Tropical Storm Yun-yeung. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. The distribution of wind speeds was also asymmetrical. Winds to tropical storm force extended out 40 miles (65 km) in the eastern side of Yun-yeung’s circulation. The winds in the eastern side of Yun-yeung were blowing at less than tropical storm force.

Tropical Storm Yun-yeung will move through an environment somewhat favorable for intensification during the next 24 hours. Yun-yeung will move over water where the Sea Surface Temperatures are near 28°C. It will move under the eastern side on an upper level ridge south of Japan. The upper level ridge will produce northeasterly winds that will blow toward the top of Yun-yeung’s circulation. Those winds will cause moderate vertical wind shear. The wind shear is already contributing to the asymmetrical distribution of thunderstorms. The vertical wind shear will inhibit intensification, but the shear will probably not be strong enough to prevent Yun-yeung from strengthening. Tropical Storm Yun-yeung is likely to intensify gradually during the next 24 hours.

Tropical Storm Yun-yeung will move around the northwestern part of high pressure system over the Western North Pacific. The high pressure system will steer Yun-yeung toward the north-northeast during the next 24 hours. On its anticipated track, Tropical Storm Yun-yeung will move closer to Honshu. Yun-yeung could be near Tokyo in 48 hours.

Tropical Storm Lee Forms East of the Lesser Antilles

Tropical Storm Lee formed east of the Lesser Antilles on Tuesday afternoon. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Lee was located at latitude 13.2°N and longitude 41.8°W which put it about 1315 miles (2115 km) east of the Lesser Antilles. Lee was moving toward the west-northwest at 16 m.p.h. (26 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 1005 mb.

A low pressure system within a tropical wave over the Atlantic Ocean east of the Lesser Antilles strengthened on Tuesday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Lee. More thunderstorms developed near the center of Lee’s circulation during the afternoon. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center started to generate upper level divergence that pumped mass away form the tropical storm. Winds to tropical storm force extended out 65 miles (105 km) from the center of Tropical Storm Lee.

Tropical Storm Lee will move through an environment favorable for intensification during the next 36 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. Tropical Storm Lee will intensify during the next 36 hours. Lee could strengthen to a hurricane by Thursday.

Tropical Storm 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, Tropical Storm Lee could be northeast of the Leeward Islands by Friday night.

Tropical Storm Jova Forms South of Mexico

Tropical Storm Jova formed south of Mexico on Monday night. At 5:00 a.m. EDT on Tuesday the center of Tropical Storm Jova was located at latitude 12.8°N and longitude 106.9°W which put it about 725 miles (1165 km) south-southeast of the southern tip of Baja California. Jova was moving toward the west 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 1004 mb.

A low pressure system over the Eastern North Pacific Ocean south of Mexico strengthened during Monday night and the U.S. National Hurricane Center designated the system as Tropical Storm Jova. The circulation around Jova was still organizing on Tuesday morning. It was difficult to see the surface center of Tropical Storm Jova on infrared satellite images. More thunderstorms were developing in bands revolving around the center of circulation. Winds to tropical storm force extended out 60 miles (95 km) in the northeastern quadrant of Jova’s circulation. The winds in the other parts of Tropical Storm Jova were blowing at less than tropical storm force.

Tropical Storm Jova will move through an environment favorable for intensification during the next 36 hours. Jova will move over water where the Sea Surface Temperatures are near 29°C. It will move under the southern part of an upper level ridge over Mexico and the Eastern North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Jova’s circulation. The winds in the lower levels of the atmosphere will also blow from the east and there will be little vertical wind shear. Tropical Storm Jova will intensify during the next 36 hours. Jova could strengthen to a hurricane on Wednesday.

Tropical Storm 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 36 hours. On its anticipated track, Tropical Storm Jova will move farther away from the west coast of Mexico.

Tropical Storm Haikui Makes Landfall near Shantou, China

The center of Tropical Storm Haikui made landfall on the coast of eastern China near Shantou on Monday. At 5:00 p.m. EDT on Monday the center of Tropical Storm Haikui was located at latitude 23.7°N and longitude 117.0°E which put it about 15 miles (20 km) northeast of Shantou, China. Haikui was moving toward the west at 13 m.p.h. (21 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 996 mb.

Former Typhoon Haikui weakened to a tropical storm as it moved across the Taiwan Strait. The lower levels of circulation around Haikui were disrupted by the mountains on Taiwan. The disruption caused Haikui to weaken steadily before it made landfall in China. Many of the bands revolving around the center of Tropical Storm Haikui consisted primarily of showers and lower clouds. There were thunderstorms in a band just to the south of the center of Haikui’s circulation. There were also thunderstorms in a band in the eastern side of Tropical Storm Haikui.

Tropical Storm Haikui will move toward the west over eastern China. Haikui will weaken to a tropical depression as it moves inland. Tropical Storm Haikui will bring gusty winds and isolated heavy rain to eastern Guangdong province.

Typhoon Haikui Moves over the Taiwan Strait

Typhoon Haikui moved over the Taiwan Strait on Sunday night. At 11:00 p.m. EDT on Sunday the center of Typhoon Haikui was located at latitude 23.3°N and longitude 119.6°E which put it about 70 miles (110 km) northwest of Kaohsiung, Taiwan. Haikui was moving toward the west-northwest at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 966 mb.

Typhoon Haikui brought strong winds and heavy rain to Taiwan on Sunday. A weather station at the airport in Taipei (RCTP) reported a sustained wind speed of 35 m.p.h. (55km/h) and a wind gust of 49 m.p.h. (79 km/h). A weather station in Taitung (RCFN) reported a sustained wind speed of 56 m.p.h. (91 km/h) and a wind gust of 87 m.p.h. (140 km/h). A weather station in Kaohsiung (RCKH) reported a sustained wind speed of 39 m.p.h. (63 km/h) and a wind gust of 62 m.p.h. (100 km/h). Bands in the eastern part of Typhoon Haikui were still dropping heavy rain over parts of Taiwan on Sunday night.

The lower levels of the circulation of Typhoon Haikui were disrupted when Haikui moved over the mountains on Taiwan. There was no longer an eye at the center of Haikui’s circulation. The circulation in the middle and upper level of Typhoon Haikui remained relatively intact. Bands of showers and thunderstorms were revolving around the center of Haikui’s circulation. Winds to typhoon force extended out 30 miles (50 km/h) from the center of circulation. Winds to tropical storm force extended out 165 miles (265 km) from the center of Typhoon Haikui.

Typhoon Haikui will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Haikui toward the west-northwest during the next 24 hours. On its anticipated track, the center of Typhoon Haikui will approach the east coast of China between Shantou and Xiamen within 24 hours.

Typhoon Haikui will move through an environment favorable for intensification during the next 24 hours. Haikui will move over water where the Sea Surface Temperatures are near 30°C. It will move under an upper level ridge centered northwest of Taiwan. The upper level winds are weak in the ridge and the will be little vertical wind shear. Typhoon Haikui may not intensify during the next 24 hours even though it will move through a favorable environment. The lower levels of Haikui’s circulation will gradually reorganize now that the center of circulation is back over water. However, there may not be enough time for an eye to develop again before Haikui reaches the east coast of China. If the inner core of Typhoon Haikui does not develop again, then it will be unlikely to strengthen.

Typhoon Haikui Hits Taiwan

Typhoon Haikui hit Taiwan on Sunday morning. At 5:00 a.m. EDT on Sunday the center of Typhoon Haikui was located at latitude 22.9°N and longitude 121.1°E which put it about 20 miles (30 km) northeast of Taitung, Taiwan. Haikui was moving toward the west at 12 m.p.h. (19 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 947 mb.

The center of Typhoon Haikui made landfall on the southeast coast of Taiwan just to the northeast of Taitung on Sunday morning. Haikui intensified to the equivalent of a major hurricane as it approached the coast of Taiwan. The Hurricane Intensity Index (HII) for Typhoon Haikui was 22.1. The Hurricane Size Index (HSI) was 13.0 and the Hurricane Wind Intensity Size Index (HWISI) was 35.1. Typhoon Haikui was similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

Typhoon Haikui brought strong, gusty winds and heavy rain to Taiwan. Winds to typhoon force extended out 40 miles (65 km) from the center of Haikui’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

The center of Typhoon Haikui will move across southern Taiwan during the next few hours. Haikui’will produce strong, gusty winds in much of Taiwan. Typhoon Haikui is capable of causing regional major damage. Widespread outages of electricity are likely. Heavy rains will cause flash floods, especially near mountains.

The center of Typhoon Haikui will be near Kaohsiung in a few hours. Haikui will weaken as it moves across southern Taiwan. Mountains in Taiwan could will disrupt the circulation in the lower levels of Typhoon Haikui. The circulation in the middle and upper troposphere will remain move relatively intact. Haikui will move over the South China Sea later on Sunday. Typhoon Haikui could approach the coast of China near Shantou in less than 36 hours.

Typhoon Haikui Nears Taiwan

Typhoon Haikui neared Taiwan on Saturday. At 5:00 p.m. EDT on Saturday the center of Typhoon Haikui was located at latitude 22.6°N and longitude 122.7°E which put it about 100 miles (160 km) east-southeast of Taitung, Taiwan. Haikui was moving toward the west at 13 m.p.h. (21 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 958 mb.

Typhoon Haikui intensified as it neared Taiwan on Saturday. A small circular eye was at the center of Haikui’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 Haikui. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The Taiwan Central Weather Bureau’s radar images indicated that Typhoon Haikui was very symmetrical. Winds to typhoon force extended out 35 miles (55 km) from the center of Haikui’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Haikui was 17.8. The Hurricane Size Index (HSI) was 9.7 and the Hurricane Wind Intensity Size Index (HWISI) was 27.5. Typhoon Haikui was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Typhoon Haikui will move through an environment favorable for intensification during the next few hours. Haikui 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 centered north of Taiwan. The ridge will produce easterly winds that will blow toward the top of Haikui’s circulation. The winds in the lower levels of the atmosphere will also blow from the east. So, there will be little vertical wind shear. Typhoon Haikui is likely to continue to intensify during the next few hours until it makes landfall on Taiwan.

Typhoon Haikui will move around the southern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Haikui toward the west- northwest during the next 24 hours. On its anticipated track, the center of Typhoon Haikui will move landfall on the coast of southeast Taiwan near Taitung in nine hours.

Typhoon Haikui will bring strong winds and heavy rain to Taiwan. Haikui will be capable of causing regional serious damage. The heaviest rain will fall on the eastern sides of mountains where the wind will push air up the slopes. Heavy rain is likely to cause flash floods.

Elsewhere over the Western North Pacific Ocean, former Typhoon Saola weakened to a tropical storm along the coast of southern China and former Tropical Storm Kirogi weakened to a tropical depression south of Japan. At 5:00 p.m. EDT on Saturday the center of Tropical Storm Saola was located at latitude 21.6°N and longitude 109.5°E which put it about 35 miles (55 km) east-northeast of Beihai, China. Saola was moving toward the west-southwest at 7 m.p.h. (11 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 991 mb.

At 5:00 p.m. EDT on Saturday the center of Tropical Depression Kirogi was located at latitude 29.6°N and longitude 142.0°E which put it about 370 miles (595 km) south-southeast of Tokyo, Japan. Kirogi was moving toward the northwest at 22 m.p.h. (35 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1000 mb.