Monthly Archives: August 2025

Hurricane Erin Rapidly Intensifies to Cat. 5

Hurricane Erin rapidly intensified to Category 5 on the Saffir-Simpson Scale on Saturday morning.   At 11:00 a.m. EDT on Saturday the center of Hurricane Erin was located at latitude 19.7°N and longitude 62.8°W which put the center about 105 miles (165 km) north of Anguilla.    Erin was moving toward the west at 17 m.p.h. (28 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 917 mb.

Tropical Storm Watches are in effect for  St. Martin, St. Barthelemy, and Sint Maarten.

Hurricane Erin rapidly intensified to a Category 5 hurricane on the Saffir-Simpson Scale on Saturday morning.  A small circular eye with a diameter of 6 miles (10 km) was at the center of Erin’s circulation.  A ring of thunderstorms surrounded the eye and the strongest winds winds occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Hurricane Erin.  Storms near the center of Erin 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 circulation around Hurricane Erin is small.  Winds to hurricane force extend out 30 miles (50 km) from the center of Erin’s circulation.  Winds to tropical storm force extend out 140 miles (220 km) in the northern side of Hurricane Erin.  Winds to tropical storm force extend out 60 miles in the southern half of Erin’s circulation.

The Hurricane Intensity Index (HII) is 35.0. The Hurricane Size Index (HSI) is 9.2 and the Hurricane Wind Intensity Size Index (HWISI) is 44.2. Hurricane Erin is similar in intensity to Hurricane Michael in 2018.  Erin is smaller than Michael was.

Hurricane Erin will move through an environment that will be favorable for intensification during the next 24 hours.  Erin 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 Erin is likely to continue to intensify during the next few hours.  However, it is likely that the inner end of a rainband will wrap around the existing eye and eyewall.  That would create concentric eyewalls.  It would also start an eyewall replacement cycle.  An eyewall replacement cycle would cause Hurricane Erin to weaken, at least temporarily.

Hurricane Erin will move around the southern side of a high pressure system over the Atlantic Ocean.  The high pressure system will steer Erin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Storm Erin will pass north of the Puerto Rico on Saturday night.

Bands in the southern side of Hurricane Erin are likely to bring gusty winds and locally heavy rain to the Northern Leeward Islands and to the Virgin Islands.  Heavy rain could cause flash floods in some locations.  Bands feeding into the southern side of Hurricane Erin could also drop heavy rain on Puerto Rico.

A Flood Watch is in effect for Puerto Rico.

Hurricane Erin Rapidly Intensifies to Cat. 4

Hurricane Erin rapidly intensified to Category 4 on the Saffir-Simpson Scale on Saturday morning.  At 8:00 a.m. EDT on Saturday the center of Hurricane Erin was located at latitude 19.6°N and longitude 62.0°W which put the center about 120 miles (195 km) northeast of Anguilla.   Erin was moving toward the west-northwest at 20 m.p.h. (32 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 935 mb.

Tropical Storm Watches are in effect for  St. Martin, St. Barthelemy, and Sint Maarten.

Hurricane Erin rapidly intensified to a Category 4 hurricane on the Saffir-Simpson Scale early on Saturday morning.  A circular eye with a diameter of 12 miles (19 km) was at the center of Erin’s circulation.  A ring of thunderstorms surrounded the eye and the strongest winds winds occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Hurricane Erin.  Storms near the center of Erin 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 circulation around Hurricane Erin is small.  Winds to hurricane force extend out 30 miles (50 km) from the center of Erin’s circulation.  Winds to tropical storm force extend out 130 miles (210 km) in the northern side of Hurricane Erin.  Winds to tropical storm force extend out 60 miles in the southern half of Erin’s circulation.

The Hurricane Intensity Index (HII) is 29.9.  The Hurricane Size Index (HSI) is 8.4 and the Hurricane Wind Intensity Size Index (HWISI) is 38.3.  Hurricane Erin is similar in size and intensity to Hurricane Charley in 2004.

Hurricane Erin will move through an environment that will be very favorable for intensification during the next 24 hours.  Erin 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 Erin will intensity during the next 24 hours.  Erin could strengthen to Category 5 on the Saffir-Simpson Scale.

Hurricane Erin will move around the southern side of a high pressure system over the Atlantic Ocean.  The high pressure system will steer Erin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Storm Erin will pass north of the Puerto Rico on Sunday.

Bands in the southern side of Hurricane Erin are likely to bring gusty winds and locally heavy rain to the Northern Leeward Islands.  Heavy rain could cause flash floods in some locations.  Bands feeding into the southern side of Hurricane Erin could also drop heavy rain on Puerto Rico.

A Flood Watch is in effect for Puerto Rico.

Erin Strengthens to a Hurricane

Former Tropical Storm Erin strengthened to a hurricane east of the Northern Leeward Islands on Friday.  At 11:00 a.m. EDT on Friday the center of Hurricane Erin was located at latitude 18.2°N and longitude 56.1°W which put the center about 460 miles (740 km) east of the Northern Leeward Islands.  Erin was moving toward the west-northwest at 18 m.p.h. (30 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 996 mb.

Tropical Storm Watches are in effect for Anguilla, Barbuda, St. Martin, St. Barthelemy, Saba, St. Eustatius, and Sint Maarten.

Former Tropical Storm Erin strengthened to a hurricane east of the Northern Leeward Islands on Friday.  The inner end of a rainband wrapped around the center of Erin’s circulation.  A small eye with a diameter of 12 miles (19 km) formed at the center of Hurricane Erin.  Bands of showers and thunderstorms were revolving around the center of Erin’s circulation.  Storms near the center generated upper level divergence that was pumping mass away from the hurricane.

The strongest winds were occurring in the northeastern part of Hurricane Erin.  Winds to hurricane force extended out 25 miles (40 km) in the northeastern quadrant of Erin’s circulation.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Hurricane Erin.

Hurricane Erin will move through an environment favorable for intensification during the next 24 hours.  Erin will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southern part of an upper level ridge over the eastern Atlantic Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Erin’s circulation. The winds in the lower levels of the atmosphere will also blow from the east, but winds will be stronger in the upper troposphere.  So, there will be some vertical wind shear.  The vertical wind shear will slightly inhibit intensification, but the shear will not be enough to prevent intensification. Hurricane Erin will intensity during the next 24 hours.  Erin is likely to strengthen to a major hurricane during the weekend.

Hurricane Erin will move around the southern side of a high pressure system over the Atlantic Ocean.  The high pressure system will steer Erin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Storm Erin will pass north of the Northern Leeward Islands on Saturday.

Bands in the southern side of Hurricane Erin are likely to bring gusty winds and locally heavy rain to the Northern Leeward Islands.  Heavy rain could cause flash floods in some locations.  Bands feeding into the southern side of Hurricane Erin could also drop heavy rain on Puerto Rico.

A Flood Watch is in effect for Puerto Rico.

Erin Prompts Tropical Storm Watches for Northern Leeward Islands

The potential risk posed by Tropical Storm Erin prompted the issuance of Tropical Storm Watches for the Northern Leeward Islands on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Erin was located at latitude 16.7°N and longitude 51.2°W which put the center about 790 miles (1270 km) east of the Northern Leeward Islands.  Erin was moving toward the west at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 998 mb.

Tropical Storm Watches are in effect for Anguilla, Barbuda, St. Martin, St. Barthelemy, Saba, St. Eustatius, and Sint Maarten.

Tropical Storm Erin continued to strengthen gradually on Thursday.  Even though Tropical Storm Erin was strengthening, the distribution of thunderstorms was asymmetrical.  Thunderstorms were occurring mainly in bands in the western side of Erin’s circulation.  Bands in the eastern side of Tropical Storm Erin consisted primarily of showers and lower clouds.  Storms near the center of Erin generated upper level divergence that pumped mass away to the west of the tropical storm.  The removal of mass caused the surface pressure to decrease slowly.

The circulation around Tropical Storm Erin is small,  Winds to tropical storm force extend out 60 miles (95 km) from the center of Erin’s circulation.

Tropical Storm Erin will move through an environment mostly favorable for intensification during the next 24 hours.  Erin will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southern part of an upper level ridge over the eastern Atlantic Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Erin’s circulation.  The winds in the lower levels of the atmosphere will also blow from the east, but winds will be stronger in the upper troposphere.  So, there will be some vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Storm Erin will intensity during the next 24 hours.  Erin is likely to strengthen to a hurricane on Friday.

Tropical Storm Erin will move around the southern side of a high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Erin toward the west during the next 24 hours.  On its anticipated track, Tropical Storm Erin will move toward the Northern Leeward Islands.  Erin could approach the Northern Leeward Islands on Friday night.

Tropical Storm Erin is likely to bring gusty winds and locally heavy rain to the Northern Leeward Islands.  Heavy rain could cause flash floods in some locations.

Tropical Storm Erin Strengthens a Little

Tropical Storm Erin strengthened a little on Wednesday as it moved over the Atlantic Ocean east of the Northern Leeward Islands.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Erin was located at latitude 16.3°N and longitude 46.6°W which put the center about 1095 miles (17635 km) east of the Northern Leeward Islands.  Erin was moving toward the west at 16 m.p.h. (26 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 1002 mb.

Tropical Storm Erin strengthened a little on Wednesday.  More thunderstorms formed near the center of Erin’s circulation.  Thunderstorms were also occurring in bands in the western side of Tropical Storm Erin.  Bands in the eastern side of Erin’s circulation consisted primarily of showers and lower clouds.  Storms near the center of Erin generated upper level divergence that pumped mass away to the west of the tropical storm.

The strongest winds were occurring in the northern side of Tropical Storm Erin.  Winds to tropical storm force extended out 60 miles (95 km) in the northern half of Erin’s circulation.  The winds in the southern side of Tropical Storm Erin were blowing at less than tropical storm force.

Tropical Storm Erin will move through an environment somewhat favorable for intensification during the next 24 hours.  Erin will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern part of an upper level ridge over the eastern Atlantic Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Erin’s circulation.  The winds in the lower levels of the atmosphere will also blow from the east, but winds will be stronger in the upper troposphere.  So, there will be some vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Storm Erin will intensity during the next 24 hours.  Erin will move over warmer water on Friday.  Erin is likely to strengthen to a hurricane on by Friday evening.

Tropical Storm Erin will move around the southern side of a high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Erin toward the west during the next 24 hours.  On its anticipated track, Tropical Storm Erin will move toward the Northern Leeward Islands.  Erin could approach the Northern Leeward Islands on Friday night.

Typhoon Podul Nears Taiwan

Typhoon Podul was nearing southern Taiwan on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Podul was located at latitude 22.3°N and longitude 122.6°E which put the center about 100 miles (160 km) east-southeast of Taitung, Taiwan.  Podul was moving toward the west-northwest at 17 m.p.h. (28 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.

Typhoon Podul was intensifying as it approached southern Taiwan on Tuesday.  A circular eye with a diameter of 30 miles (48 km) was at the center of Podul’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 center of Typhoon Podul.  Storms near the center generated upper level divergence that pumped mass away to the south and west of the typhoon.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Typhoon Podul increased as Podul intensified on Tuesday.  Winds to typhoon force extended out 60 miles (95 km) from the center of Podul’s circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center of Typhoon Podul.

The Hurricane Intensity Index (HII) for Typhoon Podul is 16.5.  The Hurricane Size Index (HSI) is 16.7 and the Hurricane Wind Intensity Size Index (HWISI) is 33.2.  Typhoon Podul is similar in intensity to Hurricane Idalia when Idalia hit Florida in 2023.  Typhoon Podul is much larger than Idalia was.

Typhoon Podul will move through an environment that will be mostly favorable for intensification during the next few hours.  Podul will move over water where the Sea Surface Temperatures are near 29°C.  An upper level ridge over eastern China will produce northeasterly winds that will blow toward the top of Podul’s circulation.  Those winds will cause moderate vertical wind shear. The vertical wind shear will inhibit intensification, but the shear may not be enough to prevent intensification.  Typhoon Podul could continue to intensify during the next few hours.

Typhoon Podul will move around the southern side of a high pressure system that is south of Japan.  The high pressure system will steer Podul toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Podul will make landfall in southeastern Taiwan in a few hours.

Typhoon Podul will bring strong gusty winds and heavy rain to Taiwan.  The heaviest rain will fall in southern Taiwan and on the eastern slopes of mountains in eastern Taiwan.  Heavy rain is likely to cause flash floods in some locations.

The Taiwan Central Weather Administration has issued a Land Typhoon Warning for much of Taiwan.  A Sea Typhoon Warning is in effect for much of the waters surrounding Taiwan.

The Taiwan Central Weather Administration has issued an Extremely Heavy Rain Advisory for much of southern and eastern Taiwan.

Typhoon Podul could also cause a storm surge of up to 10 feet (3 meters) along parts of the east coast of Taiwan.

Henriette Weakens Back to a Tropical Storm

Former Hurricane Henriette weakened back to a tropical storm over the Central Pacific Ocean north of Hawaii on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Henriette was located at latitude 32.8°N and longitude 161.6°W which put the center about 825 miles (1330 km) north-northwest of Honolulu, Hawaii.  Henriette was moving toward the northwest at 16 m.p.h. (26 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 994 mb.

Former Hurricane Henriette weakened back to a tropical storm over the Central Pacific Ocean north of Hawaii on Tuesday.  Henriette moved into a region of drier air that is northwest of Hawaii.  The drier air was pulled around the southern side of Tropical Storm Henriette.  The drier air affect the structure of Henriette.

Thunderstorms were still occurring near the center of Tropical Storm Henriette.  Thunderstorms were also still occurring in bands in the eastern and northern sides of Henriette’s circulation.  Bands in the southern and western sides of Tropical Storm Henriette consisted primarily of showers and lower clouds.

The circulation around Tropical Storm Henriette was small.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Henriette’s circulation.

Tropical Storm Henriette will move through an environment that will become more unfavorable for intensification during the next 24 hours.  Henriette will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the eastern side of an upper level low that is northwest of Hawaii.  The upper level low will produce southerly winds that will blow toward the top of Henriette’s circulation.  Those winds will cause the vertical wind shear to increase.  In addition, Henriette will continue to move through the region of drier air northwest of Hawaii.  More vertical wind shear and the effects of the drier will cause Tropical Storm Henriette to continue to weaken during the next 24 hours.

Tropical Storm Henriette will move around the southwestern part of a high pressure system over the central North Pacific Ocean.  The high pressure system will steer Henriette toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Henriette will continue to move farther away from Hawaii.

Tropical Storm Erin Churns Quickly Westward

Tropical Storm Erin churned quickly westward over the Atlantic Ocean between the Cabo Verde Islands and the Northern Lesser Antilles on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Erin was located at latitude 17.2°N and longitude 36.3°W which put the center about 1765 miles (2835 km) east of the Northern Lesser Antilles.  Erin was moving toward the west at 23 m.p.h. (37 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 Erin moved into a region of drier air on Monday night.  The drier air caused many of the thunderstorms in Erin’s circulation to dissipate.  The circulation around Tropical Storm Erin consisted primarily of bands of showers and lower clouds on Tuesday morning.  A few thunderstorms were still occurring in some of the rainbands.

The strongest winds were occurring in the northern half of Tropical Storm Erin.  Winds to tropical storm force extended out 35 miles (55 km) in the northern side of Erin’s circulation.  The winds in the southern side of Tropical Storm Erin were blowing at less than tropical storm force.

Tropical Storm Erin will move through an environment marginally favorable for intensification during the next 24 hours.  Erin will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the southern part of an upper level ridge over the eastern Atlantic Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Erin’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.  Erin will continue to move through the region of drier air today.  The drier air will inhibit intensification in the short term.  Tropical Storm Erin is likely to maintain its intensity during the next 24 hours.  Erin will move over warmer water later this week.  Tropical Storm Erin is likely to strengthen to a hurricane later this week.

Tropical Storm Erin will move around the southern side of a high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Erin toward the west during the next 24 hours.  On its anticipated track, Tropical Storm Erin will move toward the Northern Lesser Antilles.  Erin could approach the Northern Lesser Antilles at the end of this week.

Podul Strengthens to a Typhoon

Former Tropical Storm Podul strengthened to a typhoon over the Western North Pacific Ocean east-southeast of Taiwan on Monday.  At 5:00 p.m. EDT on Monday the center of Typhoon Podul was located at latitude 20.8°N and longitude 128.6°E which put the center about 510 miles (825 km) east-southeast of Taipei, Taiwan.  Podul was moving toward the west at 16 m.p.h. (26 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 984 mb.

The circulation around Typhoon Podul became more symmetrical on Monday.  A circular eye appeared at the center of Podul’s circulation.  The eye was surrounded by a broken ring of thunderstorms.  The strongest winds were occurring in that broken ring of storms.  Bands of showers and thunderstorms were revolving around the center of Typhoon Podul.  Storms near the center of Podul generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the eastern side of Typhoon Podul.  Winds to typhoon force extended out 35 miles (55 km) in the eastern side of Podul’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Typhoon Podul.

Typhoon Podul will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Podul will move over water where the Sea Surface Temperatures are near 29°C.  However, an upper level ridge over eastern China and Japan will produce northeasterly winds that will blow toward the top of Podul’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear may not be enough to prevent intensification.  Typhoon Podul could intensify during the next 24 hours if the wind shear does not get any stronger.

Typhoon Podul will move around the southern side of a high pressure system that is south of Japan.  The high pressure system will steer Podul toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Podul will approach Taiwan in 24 hours.

Typhoon Podul will bring strong winds and heavy rain to Taiwan.  Heavy rain is likely to cause flash floods in some locations.

Hurricane Henriette Moves North of Hawaii

Hurricane Henriette moved north of Hawaii on Monday.  At 5:00 p.m. EDT on Monday the center of Hurricane Henriette was located at latitude 29.8°N and longitude 157.8°W which put the center about 585 miles (945 km) north of Honolulu, Hawaii.  Henriette was moving toward the northwest at 18 m.p.h. (30 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 986 mb.

Hurricane Henriette strengthened slightly as it moved north of Hawaii on Monday.  A small clear area appeared intermittently at the center of Henriette’s circulation.  The clear area could be evidence that an eye may form at the center of Hurricane Henriette.  The clear area 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 center of Henriette’s circulation.  Storms near the center of Henriette generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Henriette was small.  Winds to tropical storm force extended out 20 miles (30 km) from the center of Henriette’s circulation.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Hurricane Henriette.

Hurricane Henriette will move through an environment mostly favorable for intensification during the next 24 hours.  Henriette will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the eastern side of an upper level low that is northwest of Hawaii.  Henriette will move north of a smaller upper level low that is north of Hawaii.  The upper level winds are weak in the zone between the two upper level lows and there will be little vertical wind shear.  Hurricane Henriette could intensify during the next 24 hours.  The upper level winds will get stronger when Henriette moves closer to the upper level low northwest of Hawaii later on Tuesday.  Henriette could start to weaken by Tuesday night.

Hurricane Henriette will move around the southwestern part of a high pressure system over the central North Pacific Ocean.  The high pressure system will steer Henriette toward the northwest during the next 24 hours.  On its anticipated track, Hurricane Henriette will move farther away from Hawaii.