Monthly Archives: August 2025

Tropical Storm Ivo Forms South of Mexico

Tropical Storm Ivo formed over the Eastern North Pacific Ocean on Wednesday afternoon.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Ivo was located at latitude 14.2°N and longitude 99.1°W which put the center about 195 miles (310 km) south-southeast Acapulco, Mexico.  Ivo was moving toward the west-northwest at 22 m.p.h. (35 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 1008 mb.

A low pressure system over the Eastern North Pacific Ocean south of Mexico strengthened on Wednesday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Ivo.

The circulation around Tropical Storm Ivo organized quickly on Wednesday afternoon.  Thunderstorms developed near the center of Ivo’s circulation.  Thunderstorms also formed in bands revolving around the center of Tropical Storm Ivo.  Storms near the center of Ivo began to generate upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Ivo was small.  Winds to tropical storm force extended out 25 miles (40 km) in the northern side of Ivo’s circulation.  The winds in the southern side of Tropical Storm Ivo were blowing at less than tropical storm force.

Tropical Storm Ivo will move through an environment mostly favorable for intensification during the next 24 hours.  Ivo will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern side of an upper level ridge over Mexico.  The upper level ridge will produce easterly winds that will blow toward the top of Ivo’s circulation.  However, the winds in the lower atmosphere will also blow from the east.  Since the winds in the upper and lower levels of the atmosphere will blow from the same direction, there will be less vertical wind shear.  Tropical Storm Ivo is likely to strengthen during the next 24 hours.

Tropical Storm Ivo will move around the southern side of a high pressure system that is over Mexico.  The high pressure system will steer Ivo toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Ivo will move parallel to the coast of southern Mexico.

Bands in the northern side of Ivo’s circulation could drop heavy rain on parts of southern Mexico.  Heavy rain could cause flash floods in Guerrero, Michoacan, and Colima.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Henriette continued to churn toward the Central Pacific.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Henriette was located at latitude 18.1°N and longitude 131.3°W which put the center about 1555 miles (2505 km) east Hilo, Hawaii.  Henriette 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 1005 mb.

Tropical Storm Dexter Moves South of Nova Scotia

Tropical Storm Dexter moved south of Nova Scotia on Tuesday evening.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Dexter was located at latitude 38.9°N and longitude 61.3°W which put the center about 410 miles (660 km) south-southeast of Halifax, Nova Scotia.  Dexter was moving toward the east-northeast at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1005 mb.

The structure of Tropical Storm Dexter did not change much on Tuesday.  Strong westerly winds in the upper troposphere were blowing toward the top of Dexter’s circulation.  Those winds were causing strong vertical wind shear.  The vertical wind shear was making the distribution of thunderstorms asymmetrical.  Thunderstorms were still forming in bands in the eastern side of Tropical Storm Dexter.  Bands in the western side of Dexter’s circulation consisted primarily of showers and lower clouds.

Winds to tropical storm force extended out 80 miles (130 km) from the center of Tropical Storm Dexter.

Tropical Storm Dexter will move through an environment unfavorable for intensification of a tropical cyclone during the next 24 hours.  Dexter will move over water where the Sea Surface Temperatures are near 26°C. An upper level trough over eastern Canada U.S. will continue to cause strong vertical wind shear.  The strong wind shear will prevent Tropical Storm Dexter from intensifying as a tropical cyclone.  However, Tropical Storm Dexter will make a transition to and extratropical cyclone during the next day or two.  Dexter is likely to get stronger when it starts to make a transition to an extratropical cyclone.

The upper level trough over eastern Canada U.S. will steer Tropical Storm Dexter toward the east-northeast during the next 24 hours. On its anticipated track, Tropical Storm Dexter will move south of Newfoundland on Wednesday.

Tropical Storm Henriette Churns Westward

Tropical Storm Henriette churned westward over the Eastern North Pacific Ocean on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Henriette was located at latitude 17.0°N and longitude 125.6°W which put the center about 1095 miles (1765 km) west-southwest of the southern tip of Baja California.  Henriette was moving toward the west-northwest 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 1003 mb.

The structure of Tropical Storm Henriette did not change much on Tuesday.  The distribution of thunderstorms in Tropical Storm Henriette continued to be asymmetrical.  Thunderstorms were occurring in bands in the western side of Henriette’s circulation.  Bands in the eastern side of Tropical Storm Henriette consisted primarily of showers and lower clouds.  Storms on the western side of the center of Henriette generated upper level divergence that pumped mass away to the west of the tropical storm.  The removal of mass in the upper levels was balanced by an inflow of mass in the lower levels of the atmosphere.  The balance of outflow and inflow of mass caused the surface pressure to remain nearly constant.

The size of the circulation around Tropical Storm Henriette increased a little on Tuesday.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Henriette’s circulation.

Tropical Storm Henriette will move through an environment marginally 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 southern side of an upper level ridge over the Eastern North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Henriette’s circulation.  Those winds will cause some vertical wind shear. The vertical wind shear will inhibit intensification.  The intensity of Tropical Storm Henriette is likely to remain nearly constant during the next 24 hours.

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

Tropical Storm Dexter Passes North of Bermuda

Tropical Storm Dexter passed north of Bermuda on Monday evening.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Dexter was located at latitude 36.8°N and longitude 65.6°W which put the center about 315 miles (415 km) north of Bermuda.  Dexter was moving toward the northeast at 13 m.p.h. (21 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 1002 mb.

An upper level trough near the east coast of the U.S. was producing strong westerly winds that were blowing toward the top of Tropical Storm Dexter.  Those winds were causing strong vertical wind shear.  The wind shear was affecting the structure of Dexter’s circulation.  Thunderstorms were occurring in bands in the eastern side of Tropical Storm Dexter.  Bands in the western side of Dexter’s circulation consisted primarily of showers and lower clouds.

The strong vertical wind shear and the asymmetrical distribution of thunderstorms were also affecting the distribution of wind speeds in Tropical Storm Dexter.  Winds to tropical storm force extended out 90 miles (145 km) in the eastern side of Dexter’s circulation.  The winds in the western side of Tropical Storm Dexter were blowing at less than tropical storm force.

Tropical Storm Dexter will move through an environment unfavorable for intensification of a tropical cyclone during the next 24 hours.  Dexter will move over water where the Sea Surface Temperatures are near 27°C.  The upper level trough near the east coast of the U.S. will continue to cause strong vertical wind shear.  The strong wind shear will prevent Tropical Storm Dexter from intensifying.  Dexter could get stronger when it starts to make a transition to an extratropical cyclone.

The upper level trough near the east coast of the U.S. will steer Tropical Storm Dexter toward the east-northeast during the next 24 hours.  On its anticipated track, Tropical Storm Dexter will move farther away from Bermuda.

Tropical Storm Henriette Forms Southwest of Baja California

Tropical Storm Henriette formed over the Eastern North Pacific Ocean southwest of Baja California on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Henriette was located at latitude 14.8°N and longitude 120.6°W which put the center about 895 miles (1440 km) southwest of the southern tip of Baja California.  Henriette was moving toward the west-northwest 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 1004 mb.

A low pressure system over the Eastern North Pacific Ocean southwest of Baja California strengthened on Monday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Henriette.

The distribution of thunderstorms in Tropical Storm Henriette was asymmetrical.  Thunderstorms were occurring in bands in the western side of Henriette’s circulation.  Bands in the eastern side of Tropical Storm Henriette consisted primarily of showers and lower clouds.  Storms near the center of Henriette 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.

The circulation around Tropical Storm Henriette was small.  Winds to tropical storm force extended out 45 miles (75 km) from the center of Henriette’s circulation.

Tropical Storm Henriette will move through an environment somewhat favorable for intensification during the next 24 hours.  Henriette will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern side of an upper level ridge over the Eastern North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Henriette’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Henriette will intensify during the next 24 hours.

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

 

Tropical Storm Dexter Forms East of North Carolina

Tropical Storm Dexter formed over the Atlantic Ocean east of North Carolina on Sunday evening.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Dexter was located at latitude 34.3°N and longitude 69.4°W which put the center about 300 miles (480km) west-northwest of Bermuda.  Dexter was moving toward the east-northeast at 12 m.p.h. (19 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 1002 mb.

A low pressure system over the Atlantic Ocean east of North Carolina strengthened on Sunday evening and the U.S. National Hurricane Center designated the system as Tropical Storm Dexter.

The appearance of the low pressure system that became Tropical Storm Dexter began to look much more like a tropical storm on Sunday evening.  More thunderstorms formed near the center of Dexter’s circulation.  There was also a well developed band of thunderstorms in the eastern side of Tropical Storm Dexter.  Bands in the western side of Dexter’s circulation still consisted primarily of showers and lower clouds.  Storms near the center of Dexter began to generate upper level divergence that pumped mass away to the east of the tropical storm.  The removal of mass caused the surface pressure to decrease.

Most of the stronger winds were occurring in the eastern side of Tropical Storm Dexter.  Winds to tropical storm force extended out 140 miles (225 km) in the eastern side of Dexter’s circulation.  Winds to tropical storm force extended out 35 miles (55 km) in the western side of Tropical Storm Dexter.

Tropical Storm Dexter will move through an environment somewhat favorable for intensification during the next 24 hours.  Dexter will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the eastern side of an upper level trough over the eastern U.S.  The upper level trough will produce southwesterly winds that will blow toward the top of Dexter’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification.  Tropical Storm Dexter is likely to intensify on Monday.

Tropical Storm Dexter will move around the northwestern part of a subtropical high pressure over the Atlantic Ocean.  The high pressure system will steer Dexter toward the east-northeast during the next 24 hours.  On its anticipated track, Tropical Storm Dexter will pass north of Bermuda during Monday night.

Gil Weakens Back to a Tropical Storm

Former Hurricane Gil weakened back to a tropical storm on Saturday over the Eastern North Pacific Ocean east of Hawaii.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Gil was located at latitude 19.5°N and longitude 132.0°W which put the center about 1500 miles (2415 km) east of Hilo, Hawaii.  Gil was moving toward the west-northwest at 21 m.p.h. (33 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 997 mb.

Former Hurricane Gil weakened back to a tropical storm on Saturday when it moved over cooler water.  Many of the thunderstorms in the western side of Gil’s circulation weakened when it moved over cooler water.  Thunderstorms were still occurring in bands in the eastern side of Tropical Storm Gil.  The thunderstorms in the eastern side of Gil’s circulation still generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass meant that Tropical Storm Gil weakened slowly.

The distribution of wind speeds in Tropical Storm Gil was relatively symmetrical.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Gil’s circulation.

Tropical Storm Gil will move through an environment mostly unfavorable for intensification during the next 24 hours.  Gil will move over water where the Sea Surface Temperatures are near 24°C.  It will move through a region where there will be little vertical wind shear.  Even though Tropical Storm Gil will move through a region where there will be little vertical wind shear, Gil is likely to continue to weaken because of the cooler water.

Tropical Storm Gil will move around the southern side of a high pressure system over the Eastern North Pacific Ocean.  The high pressure system will steer Gil toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gil will move toward Hawaii as it weakens.

Tropical Storm Bailu Forms South of Japan

Tropical Storm Bailu formed over the Western North Pacific Ocean south of Japan on Saturday.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Bailu was located at latitude 33.9°N and longitude 142.6°E which put the center about 185 miles (295 km) south of Tokyo, Japan.  Bailu was moving toward the north-northeast at 29 m.p.h. (46 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 Saturday and the Japan Meteorological Agency designated the system as Tropical Storm Bailu.

The distribution of thunderstorms in Tropical Storm Bailu was asymmetrical.  Thunderstorms were occurring in bands in the northern part of Bailu’s circulation.  Thunderstorms were also occurring in bands in the southwestern part of Tropical Storm Bailu.  Bands in the other parts of Bailu’s circulation consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Bailu was also asymmetrical.  Winds to tropical storm force extended out 175 miles (280 km) in the southern half of Bailu’s circulation.  The winds in the northern side of Tropical Storm Bailu were blowing at less than tropical storm force.

Tropical Storm Bailu will move through an environment marginally favorable for intensification during the next 24 hours.  Bailu will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the eastern side of an upper level trough that is north of Japan.  The upper level trough will produce southwesterly winds that will blow toward the top of Bailu’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification.  Tropical Storm Bailu could intensify during the next 24 hours, if the vertical wind shear does not increase.

The upper level trough north of Japan will steer Tropical Storm Bailu quickly toward the east-northeast during the next 24 hours.  On its anticipated track, Tropical Storm Bailu will move quickly away from Honshu on Sunday.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Krosa was moving rapidly away from Japan.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Krosa was located at latitude 40.2°N and longitude 152.2°E which put the center about 505 miles (820 km) east of Misawa, Japan.  Krosa was moving toward the east-northeast at 28 m.p.h. (45 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 977 mb.

Gil Strengthens to a Hurricane

Former Tropical Storm Gil strengthened to a hurricane over the Eastern North Pacific Ocean southwest of Baja California on Friday.  At 11:00 p.m. EDT on Friday the center of Hurricane Gil was located at latitude 16.5°N and longitude 125.1°W which put the center about 1080 miles (1740 km) west-southwest of the southern tip of Baja California.  Gil was moving toward the west-northwest at 20 m.p.h. (32 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 Gil strengthened to a hurricane on Friday.  The inner end of a rainband wrapped around the western and southern sides of the center of Gil’s circulation.  Bands of showers and thunderstorms were revolving around the center of Hurricane Gil.  Storms near the center of Gil generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the northeastern part of Hurricane Gil.  Winds to hurricane force extended out 25 miles (40 km) in the northeastern quadrant of Gil’s circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Hurricane Gil.

Hurricane Gil will move through an environment somewhat favorable for intensification during the next 24 hours.  Gil will move over water where the Sea Surface Temperatures are near 27°C.  It will move through a region where there will be little vertical wind shear.  However, Gil will move into a region where there is very dry air.  The dry air will inhibit intensification.  Hurricane Gil could intensify during the next 24 hours if the dry air does not penetrate to the core of Gil’s circulation.

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

Elsewhere, former Tropical Storm Iona weakened to a tropical depression as it approached the International Date Line.  At 11:00 p.m. EDT on Friday the center of Tropical Depression Iona was located at latitude 15.8°N and longitude 179.5°W which put the center about 1465 miles (2355 km) west of Honolulu, Hawaii.  Iona was moving toward the west-northwest at 17 m.p.h. (28 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 1008 mb.

Tropical Storm Krosa Passes East of Japan

Tropical Storm Krosa passed east of Japan on Friday.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Krosa was located at latitude 36.8°N and longitude 143.4°E which put the center about 130 miles (210 km) east-northeast of Tokyo, Japan.  Krosa was moving toward the north-northeast at 16 m.p.h. (26 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 972 mb.

Tropical Storm Krosa passed east of Japan on Friday.  Even though Krosa was a tropical storm, there was a clear area at the center of its circulation.  The clear area was surrounded by a broken ring of thunderstorms.  The strongest winds were occurring in that broken ring of storms.  Thunderstorms were occurring in bands in the eastern side of Tropical Storm Krosa. Bands in the western side of Krosa’s circulation consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Krosa was more symmetrical on Friday.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Krosa’s circulation.

Tropical Storm Krosa will move through an environment unfavorable for the intensification of a tropical cyclone during the next 24 hours.  Krosa will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the eastern side of an upper level trough that is north of Japan.  The upper level trough will produce southwesterly winds that will cause moderate vertical wind shear.  Cooler Sea Surface Temperatures and moderate vertical wind shear will cause Tropical Storm Krosa to start a transition to an extratropical cyclone during the next 24 hours.

The upper level trough north of Japan will steer Tropical Storm Krosa toward the east-northeast during the next 24 hours.  On its anticipated track, Tropical Storm Krosa will move away from Japan.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 13W formed south of Japan.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 13W was located at latitude 28.1°N and longitude 137.5°E which put the center about 325 miles (520 km) west-northwest of Iwo To.  Tropical Depression 13W was moving toward the northeast at 7 m.p.h. (11 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 998 mb.