Category Archives: Tropical Cyclones

Information about tropical cyclones

Genevieve Still a Tropical Storm

Tropical Storm Genevieve was still a tropical storm on Saturday evening as it approached the Central Pacific Ocean.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Genevieve was located at latitude 23.5°N and longitude 136.0°W which put the center about 1655 miles (2665 km) west of southern tip of Baja California.  Genevieve 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 1004 mb.

Tropical Storm Genevieve continued to weaken gradually on Saturday as it moved over cooler water.  Thunderstorms were still occurring in bands in the northern side of Genevieve’s circulation.  Bands in the southern side of Tropical Storm Genevieve consisted primarily of showers and lower clouds.  Storms near the center of Genevieve still generated some upper level divergence that pumped mass away to the north of the tropical storm.  The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased gradually on Saturday.

The asymmetrical distribution of thunderstorms in Tropical Storm Genevieve caused the distribution of wind speeds also to be asymmetrical.  Winds to tropical storm force extended out 140 miles (220 km) in the northern half of Genevieve’s circulation.  Winds to tropical storm force only extended out 45 miles in the southern half of Tropical Storm Genevieve.

Tropical Storm Genevieve will move through an environment that will be unfavorable for intensification during the next 24 hours.  Genevieve will move over water where the Sea Surface Temperatures are near 23.5°C.  It will move under the eastern side of an upper level trough that is east of Hawaii.  The upper level trough will produce southwesterly winds that will blow toward the top of Genevieve’s circulation.  Those winds will cause the vertical wind shear to increase on Sunday.  Tropical Storm Genevieve will continue to weaken on Sunday because of the cooler water and more vertical wind shear.

Tropical Storm Genevieve will move around the southern part of a high pressure system that is over the Eastern North Pacific Ocean.  The high pressure system will steer Genevieve toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Genevieve will move over the Central North Pacific Ocean on Sunday.  Genevieve should stay well to the northeast of Hawaii.

Typhoon Dolphin Still Moving Toward Iwo To

Typhoon Dolphin was still moving toward Iwo on Saturday evening.  At 11:00 p.m. EDT on Saturday the center of Typhoon Dolphin was located at latitude 22.9°N and longitude 152.8°E which put the center about 785 miles (1265 km) east of Iwo To.  Dolphin was moving toward the west-northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 931 mb.

Typhoon Dolphin’s intensity fluctuated a little on Saturday, but Dolphin essentially maintained it strength.  A circular eye with a diameter of 35 miles (55 km) was at the center of Dolphin’s circulation.  The eye was surrounded a ring of thunderstorms and the strongest winds occurred in that ring of storms.  Bands of showers and thunderstorms revolved around the core of Typhoon Dolphin.  Storms near the core of Dolphin generated strong upper level divergence that pumped large amounts of mass from the typhoon.  The removal of large amounts of mass in the upper levels was nearly the same as the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure remained almost constant on Saturday.

The completion of multiple eyewall replacement cycles caused the circulation around Typhoon Dolphin to become very large.  Winds to typhoon force extended out 90 miles (145 km) from the center of Dolphin’s circulation.   Winds to tropical storm force extended out 275 miles (445 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 29.9. The Hurricane Size Index (HSI) is 26.7 and the Hurricane Wind Intensity Size Index (HWISI) is 56.6.  Typhoon Dolphin is bigger and stronger than Hurricane Helene was when Helene hit Florida in 2022.

Typhoon Dolphin will move through an environment favorable for a powerful typhoon during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Dolphin is likely to maintain its intensity on Sunday.  Eyewall replacement cycles are likely to continue to cause fluctuation in the intensity of Typhoon Dolphin during the next several days.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will continue to move toward Iwo To.  The center of Dolphin will be near Iwo To in 48 hours,

Tropical Storm Genevieve Churns West of Baja California

Tropical Storm Genevieve continued to churn over the Eastern North Pacific Ocean west of Baja California on Friday.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Genevieve was located at latitude 22.6°N and longitude 131.4°W which put the center about 1370 miles (2200 km) west of southern tip of Baja California.  Genevieve was moving toward the west-northwest at 15 m.p.h. (24 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.

Tropical Storm Genevieve continued to weaken gradually on Friday as it moved over cooler water in the Eastern North Pacific Ocean west of Baja California.  Thunderstorms near the center of Genevieve’s circulation were not rising as high into the atmosphere.  Bands of showers and thunderstorms were still revolving around the center of Tropical Storm Genevieve.  Storms near the center of Genevieve generated less upper level divergence that pumped less mass away from the tropical Storm.  The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased gradually on Friday.

Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Storm Genevieve.

Tropical Storm Genevieve will move through an environment that will be unfavorable for intensification during the next 24 hours.  Genevieve will move over water where the Sea Surface Temperatures are near 24.5°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Genevieve will continue to weaken gradually on Saturday as it moves over cooler water.

Tropical Storm Genevieve will move around the southern part of a high pressure system that is over the Eastern North Pacific Ocean.  The high pressure system will steer Genevieve toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Genevieve will continue to move farther away from Baja California.

Typhoon Dolphin Moves Toward Iwo To

Typhoon Dolphin moved toward Iwo To on Friday.  At 11:00 p.m. EDT on Friday the center of Typhoon Dolphin was located at latitude 20.5°N and longitude 157.8°E which put the center about 1080 miles (1740 km) east-southeast of Iwo To.  Dolphin was moving toward the west-northwest at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 933 mb.

Typhoon Dolphin appeared to be in the middle of another eyewall replacement cycle on Friday evening.  A circular eye with a diameter of 20 miles (32 km) was at the center of Dolphin’s circulation.  The eye was surrounded by two circular eyewalls.  Bands of showers and thunderstorms revolved around the core of Typhoon Dolphin.  Storms near the core of Dolphin generated strong upper level divergence that pumped large amounts of mass from the typhoon.  The removal of large amounts of mass in the upper levels was slightly less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased gradually on Friday.

The size of the circulation around Typhoon Dolphin increased on Friday.  Winds to typhoon force extended out 60 miles (95 km) from the center of Dolphin’s circulation.  Winds to tropical storm force extended out 230 miles (370 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 29.9.  The Hurricane Size Index (HSI) is 23.3 and the Hurricane Wind Intensity Size Index (HWISI) is 53.2.  Typhoon Dolphin is similar in size and intensity to Hurricane Helene when Helene hit Florida in 2022.

Typhoon Dolphin will move through an environment favorable for a powerful typhoon during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Dolphin is likely to maintain its intensity on Saturday.  Eyewall replacement cycles are likely to continue to cause fluctuation in the intensity of Typhoon Dolphin during the next few days.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will continue to move toward Iwo To.  The center of Dolphin could be near Iwo To in 72 hours,

Typhoon Dolphin Moves West of Wake Island

Typhoon Dolphin moved west of Wake Island on Thursday.  At 11:00 p.m. EDT on Thursday the center of Typhoon Dolphin was located at latitude 18.6°N and longitude 161.5°E which put the center about 315 miles (510 km) west-southwest of Wake Island.  Dolphin was moving toward the west-northwest at 12 m.p.h. (19 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 924 mb.

Typhoon Dolphin appeared to go through another eyewall replacement cycle.  A circular eye with a diameter of 30 miles (50 km) was present at the center of Dolphin’s circulation on Thursday evening.  The eye was surrounded by a ring of thunderstorms.  The strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms revolved around the core of Typhoon Dolphin.  Storms near the core of Dolphin generated strong upper level divergence that pumped large amounts of mass from the typhoon.  The removal of large amounts of mass in the upper levels was nearly equal to the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure  did not change much on Thursday.

The completion of another eyewall replacement cycle increased the size of the circulation around Typhoon Dolphin.  Winds to typhoon force extended out 60 miles (95 km) from the center of Dolphin’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 33.3.  The Hurricane Size Index (HSI) is 21.0 and the Hurricane Wind Intensity Size Index (HWISI) is 54.3.  Typhoon Dolphin is similar in intensity to Hurricane Ian when Ian hit Southwest Florida in 2022.  Typhoon Dolphin is larger than Ian was.

Typhoon Dolphin will move through an environment favorable for a powerful typhoon during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Dolphin is likely to maintain its intensity on Friday.  Eyewall replacement cycles are likely to cause fluctuation in the intensity of Typhoon Dolphin during the next few days.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will move toward Iwo To.

Genevieve Weakens to a Tropical Storm

Former Hurricane Genevieve weakened to a tropical storm on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Genevieve was located at latitude 21.3°N and longitude 126.0°W which put the center about 1035 miles (1665 km) west of southern tip of Baja California.  Genevieve was moving toward the west-northwest at 15 m.p.h. (24 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 989 mb.

Former Hurricane Genevieve continued to weaken gradually on Thursday as it moved over cooler water in the Eastern North Pacific Ocean west of Baja California.  Thunderstorms were still occurring near the center of Genevieve’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Genevieve.  Storms near the center of Genevieve still generated upper level divergence that pumped mass away from the hurricane.  However, the removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure continued to increase on Thursday.

Winds to tropical storm force extended out 125 miles (200 km) from the center of Tropical Storm Genevieve.

Tropical Storm Genevieve will move through an environment that will be unfavorable for intensification during the next 24 hours.  Genevieve 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 Genevieve will continue to weaken on Friday as it moves over cooler water.

Tropical Storm Genevieve will move around the southwestern part of a high pressure system that is over the Southwest U.S.  The high pressure system will steer Genevieve toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Genevieve will continue to move farther away from Baja California.

Hurricane Genevieve Continues to Weaken

Hurricane Genevieve continued to weaken as it moved over the Eastern North Pacific Ocean southwest of Baja California on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Genevieve was located at latitude 19.6°N and longitude 120.8°W which put the center about 735 miles (1185 km) west-southwest of southern tip of Baja California.  Genevieve was moving toward the west-northwest at 9 m.p.h. (15 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 970 mb.

Hurricane Genevieve continued to weaken gradually on Wednesday as it moved over cooler water in the Eastern North Pacific Ocean southwest of Baja California.  An eye was no longer visible on satellite imagery, but thunderstorms were still occurring near the center of Genevieve’s circulation.  Bands of showers and thunderstorms were revolving around the center of Hurricane Genevieve.  Storms near the center of Genevieve still generated upper level divergence that pumped mass away from the hurricane.  However, the removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased on Wednesday.

The distribution of wind speeds around Hurricane Genevieve was fairly symmetrical.  Winds to hurricane force extended out 30 miles (50 km) from the center of Genevieve’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Hurricane Genevieve.

Hurricane Genevieve will move through an environment that will be unfavorable for intensification during the next 24 hours.  Genevieve will move over water where the Sea Surface Temperatures are near 25°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Genevieve will continue to weaken on Thursday as it moves over cooler water.  Genevieve could weaken to a tropical storm by Friday.

Hurricane Genevieve will move around the southwestern part of a high pressure system that is over the Southwest U.S.  The high pressure system will steer Genevieve toward the west-northwest during the next 24 hours.  On its anticipated track, Hurricane Genevieve will move farther away from Baja California.

Typhoon Dolphin Strengthens to Equivalent of Cat. 5 Hurricane

Typhoon Dolphin strengthened to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale as it moved over the Western North Pacific Ocean south of Wake Island on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Dolphin was located at latitude 16.0°N and longitude 166.3°E which put the center about 240 miles (390 km) south of Wake Island.  Dolphin was moving toward the northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 165 m.p.h. (265 km/h) and there were wind gusts to 200 m.p.h. (320 km/h).  The minimum surface pressure was 915 mb.

Typhoon Dolphin strengthened to the equivalent of a Category 5 hurricane on Wednesday.  A  circular eye with a diameter of 20 miles (32 km) was present at the center of Dolphin’s circulation.  The eye was surrounded by a ring of thunderstorms. The strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms revolved around the core of Typhoon Dolphin.  Storms near the core of Dolphin generated strong upper level divergence that pumped large amounts of mass from the typhoon. The removal of large amounts of mass caused the surface pressure to decrease.

The distribution of wind speeds in Typhoon Dolphin was symmetrical.  Winds to typhoon force extended out 40 miles (65 km) from the center of Dolphin’s circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 36.7.  The Hurricane Size Index (HSI) is 15.5 and the Hurricane Wind Intensity Size Index (HWISI) is 52.2.  Typhoon Dolphin is similar in intensity to Hurricane Otis when Otis hit Mexico in 2023.  Typhoon Dolphin is larger than Otis was.

Typhoon Dolphin will move through an environment favorable for a powerful typhoon during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Dolphin could continue to intensify during the next few hours.  Eyewall replacement cycles are likely to cause fluctuation in the intensity of Typhoon Dolphin during the next few days.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will be east of Iwo To by the end of the weekend.

Tropical Storm Fausto Passes Northeast of Hawaii

Tropical Storm Fausto was weakening as it passed northeast of Hawaii on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Fausto was located at latitude 22.5°N and longitude 152.2°W which put the center about 270 miles (435 km) northeast of Hilo, Hawaii.  Fausto was moving toward the west-northwest at 12 m.p.h. (19 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 1005 mb.

Tropical Storm Fausto was weakening as it passed northeast of Hawaii on Tuesday afternoon.  An upper level trough that was located north of Hawaii was producing strong southwesterly winds that were blowing across the top of Fausto’s circulation.  Those winds were causing strong vertical wind shear.  The strong upper level winds were also blowing the tops off of many of the thunderstorms in Tropical Storm Fausto.

Thunderstorms were still occurring in bands in the eastern edge of Tropical Storm Fausto.  Bands in the other parts of Fausto’s circulation consisted primarily of showers and lower clouds.  There were no thunderstorms near the center of Fausto to generate upper level divergence to pump mass away from the tropical storm.  Convergence of mass in the lower levels of the atmosphere was causing the surface pressure to increase.

The strongest winds were blowing on the northern side of Tropical Storm Fausto.  Winds to tropical storm force extended out 140 miles (220 km) in the northern side of Fausto’s circulation.  Winds to tropical storm force only extended out 70 miles (110 km) in the southern side of Tropical Storm Fausto.

Tropical Storm Fausto will move through an environment that will be unfavorable for intensification during the next 24 hours.  Fausto will move over water where the Sea Surface Temperatures are near 26°C.  However, the upper level trough north of Hawaii will continue to cause strong vertical wind shear.  Tropical Storm Fausto will continue to weaken steadily during the next 24 hours.  Fausto is likely to weaken to a tropical depression on Wednesday.

Tropical Storm Fausto will move around the southern side of a high pressure system that is over the Central North Pacific Ocean.  The high pressure system will steer Fausto toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Fausto will continue to pass north of Hawaii on Wednesday.

Elsewhere, Hurricane Genevieve was weakening gradually as it moved southwest of Baja California.  At 5:00 p.m. EDT on Tuesday the center of Hurricane Genevieve was located at latitude 18.0°N and longitude 116.9°W which put the center about 565 miles (910 km) southwest of southern tip of Baja California.  Genevieve was moving toward the west-northwest at 9 m.p.h. (15 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 955 mb.

Typhoon Dolphin Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Dolphin rapidly intensified to the equivalent of a major hurricane as it moved over the Western North Pacific Ocean southeast of Wake Island.  At 11:00 a.m. EDT on Tuesday the center of Typhoon Dolphin was located at latitude 13.6°N and longitude 170.3°E which put the center about 490 miles (790 km) southeast of Wake Island.  Dolphin was moving toward the west at 12 m.p.h. (19 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. (2350 km/h).  The minimum surface pressure was 960 mb.

Typhoon Dolphin rapidly intensified to the equivalent of a major hurricane on Tuesday morning.  A very small circular eye was present at the center of Dolphin’s circulation.  The eye was surrounded by a ring of thunderstorms.  The strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms revolved around the core of Typhoon Dolphin.  Storms near the core of Dolphin generated strong upper level divergence that pumped large amounts of mass from the typhoon.  The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The circulation around Typhoon Dolphin was small.  Winds to typhoon force extended out 20 miles (30 km) from the center of Dolphin’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Typhoon Dolphin.

Typhoon Dolphin will move through an environment that will be very favorable for intensification during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Dolphin will intensify during the next 24 hours.  Dolphin could continue to intensify rapidly during the next few hours.  Typhoon Dolphin is likely to strengthen to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale on Thursday.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will pass south of Wake Island on Wednesday.