Monthly Archives: July 2025

Tropical Storm Krosa Spins Southeast of Japan

Tropical Storm Krosa was still spinning over the Western North Pacific Ocean southeast of Japan on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Krosa was located at latitude 32.0°N and longitude 141.9°E which put the center about 290 miles (465 km) south-southeast of Tokyo, Japan.  Krosa was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 980 mb.

The structure of Tropical Storm Krosa started to change on Thursday as it continued to spin over the Western North Pacific Ocean southeast of Japan.  The inner end of a rainband wrapped around the eastern and northern sides of the center of Krosa’s circulation.  A large circular eye appeared to be forming at the center of Krosa, even through Krosa was just a tropical storm.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Krosa.

The circulation around Tropical Storm Krosa was relatively small for a tropical storm southeast of Japan.  Winds to tropical storm force extended out 110 miles (175 km) from the center of Krosa’s circulation.

Tropical Storm Krosa will move through an environment somewhat favorable for intensification during the next 24 hours.  Krosa will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the middle of an upper level low that is southeast of Japan.  The upper level winds are weak near the center of the upper level low and there will be little vertical wind shear.  However, the upper level low will inhibit upper level divergence.  In addition, Krosa’s circulation is surrounded by drier air.  Tropical Storm Krosa could intensify during the next 24 hours in spite of the effects of the upper level low and the drier air.

Tropical Storm Krosa will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Krosa toward the north during the next 24 hours.  On its anticipated track, the center of Tropical Storm Krosa could pass to the east of Tokyo on Friday.

Tropical Storm Gil Forms South of Baja California

Tropical Storm Gil formed over the Eastern North Pacific Ocean south of Baja California on Wednesday night.  At 5:00 a.m. EDT on Thursday the center of Tropical Storm Gil was located at latitude 12.7°N and longitude 115.1°W which put the center about 785 miles (1260 km) south-southwest of the southern tip of Baja California.  Gil was moving toward the west 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 south of Baja California strengthened on Wednesday night and the U.S. National Hurricane Center designated the system as Tropical Storm Gil.

The circulation around Tropical Storm Gil was organizing quickly on Thursday morning.  Numerous thunderstorms formed near the center of Gil’s circulation.  Thunderstorms also developed in bands revolving around the center of Tropical Storm Gil.  Storms near the center of Gil generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speed in Tropical Storm Gil was asymmetrical.  Winds to tropical storm force extended out 160 miles (260 km) in the eastern side of Gil’s circulation.  Winds to tropical storm force extended out 60 miles (95 km) in the western side of Tropical Storm Gil.

Tropical Storm Gil will move through an environment very favorable for intensification during the next 24 hours.  Gil will move over water where the Sea Surface Temperatures are near 28°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 Gil’s circulation.  However, the winds in the lower atmosphere will also blow from the east.  So, there will be little vertical wind shear.  Tropical Storm Gil will intensify during the next 24 hours.  Gil could intensify rapidly,  Tropical Storm Gil could strengthen to a hurricane by Friday.

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 away from Baja California.

Elsewhere, Tropical Storm Iona moved quickly away from Hawaii.  At 5:00 a.m. EDT on Thursday the center of Tropical Storm Iona was located at latitude 12.3°N and longitude 166.9°W which put the center about 860 miles (1385 km) southwest of Honolulu, Hawaii.  Iona was moving toward the west at 23 m.p.h. (37 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 1001 mb.

Iona Rapidly Weakens to a Tropical Storm

Former Hurricane Iona rapidly weakened to a tropical storm over the Central Pacific Ocean southwest of Hawaii on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Iona was located at latitude 11.7°N and longitude 162.6°W which put the center about 730 miles (1180 km) south-southwest of Honolulu, Hawaii.  Iona was moving toward the west at 22 m.p.h. (35 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 994 mb.

Former Hurricane Iona rapidly weakened to a tropical storm southwest of Hawaii on Wednesday.  Iona moved into a region of drier air.  The drier air caused many of the thunderstorms in Iona’s circulation to dissipate.  A few thunderstorms were still occurring in bands in the southern and eastern periphery of Tropical Storm Iona.  An upper level trough southwest of Hawaii was producing southwesterly winds that were blowing toward the top of Iona’s circulation.  Those winds were causing moderate vertical wind shear.  The vertical wind shear was also contributing to the weakening of Tropical Storm Iona.

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

Tropical Storm Iona will move through an environment that will be mostly unfavorable for intensification during the next 24 hours.  Iona will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southeastern part of the upper level trough southwest of Hawaii.  The upper level trough will continue to produce southwesterly winds that will blow toward the top of Iona’s circulation.  Those winds will continue to cause moderate vertical wind shear.  In addition, Iona will also continue to move through the region of drier air that is located southwest of Hawaii.  The combination of moderate vertical wind shear and drier air will cause Tropical Storm Iona to start to continue to weaken during the next 24 hours.

Tropical Storm Iona will move around the southern side of a high pressure system over the Central Pacific Ocean.  The high pressure system will steer Iona toward the west during the next 24 hours.  On its anticipated track, Hurricane Iona will move farther away from of Hawaii on Thursday.

Elsewhere over the Central Pacific Ocean, the upper level trough southwest of Hawaii caused former Tropical Storm Keli to weaken to a tropical depression.  At 5:00 p.m. EDT on Wednesday the center of Tropical Depression Keli was located at latitude 13.9°N and longitude 156.6°W which put the center about 520 miles (835 km) south of Honolulu, Hawaii.  Keli was moving toward the west 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 1006 mb.

Tropical Storm Co-may Moves Inland Near Shanghai

Tropical Storm Co-may moved inland over eastern China near Shanghai on Wednesday.  At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Co-may was located at latitude 31.4°N and longitude 121.1°E which put the center about 5 miles (10 km) west of Shanghai, China.  Co-may was moving toward the northwest at 7 m.p.h. (11 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 979 mb.

The center of Tropical Storm Co-may made landfall on the coast of eastern China near Shanghai on Wednesday.  Co-may was weakening as it made landfall.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Co-may’s circulation.

Tropical Storm Co-may will move around the southwestern part of a high pressure system over northeastern China.  The high pressure system will steer Co-may toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Tropical Storm Co-may will move inland west of Shanghai during the next 24 hours.

Tropical Storm Co-may will bring gusty winds and rain to the region around Shanghai.  Locally heavy rain could cause floods in Zhejiang and Jiangsu.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Krosa was stalled southeast of Japan.  At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Krosa was located at latitude 29.2°N and longitude 143.2°E which put the center about 475 miles (765 km) south-southeast of Tokyo, Japan.  Krosa was moving toward the northwest at 2 m.p.h. (3 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 985 mb.

Hurricane Iona Passes South of Hawaii

Hurricane Iona was passing well to the south of Hawaii on Tuesday afternoon.  At 5:00 p.m. EDT on Tuesday the center of Hurricane Iona was located at latitude 10.9°N and longitude 155.7°W which put the center about 735 miles (11800 km) south-southeast of Honolulu, Hawaii.  Iona was moving toward the west at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 957 mb.

Hurricane Iona strengthened a little more on Tuesday afternoon as it passed well to the south of Hawaii.  A small circular eye was still visible at the center of Iona’s circulation on satellite images.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Hurricane Iona.  Storms near the center of Iona generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Hurricane Iona increased a little on Tuesday afternoon, but Iona was still a small hurricane.  Winds to hurricane force extended out 30 miles (50 km) from the center of Iona’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Hurricane Iona.

Hurricane Iona will move through an environment that will become unfavorable for intensification during the next 24 hours.  Iona will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southeastern part of an upper level trough centered north of Hawaii.  The upper level trough will produce southwesterly winds that will blow toward the top of Iona’s circulation.  Those winds will cause the vertical wind shear to increase.  In addition, Iona will move into a region of drier air that is located southwest of Hawaii.  The combination of more vertical wind shear and drier air will cause Hurricane Iona to start to weaken during the next 24 hours.

Hurricane Iona will move around the southern side of a high pressure system over the Central Pacific Ocean.  The high pressure system will steer Iona toward the west during the next 24 hours.  On its anticipated track, Hurricane Iona will move southwest of Hawaii on Wednesday.

Elsewhere over the Central Pacific Ocean, Tropical Storm Keli continue to move toward the west behind Hurricane Iona.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Keli was located at latitude 12.8°N and longitude 149.9°W which put the center about 790 miles (1270 km) southeast of Honolulu, Hawaii.  Keli was moving toward the west at 15 m.p.h. (24 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 1006 mb.

Tropical Storm Co-may Nears Eastern China

Tropical Storm Co-may neared the coast of eastern China on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Co-may was located at latitude 28.9°N and longitude 123.1°E which put the center about 215 miles (345 km) south-southeast of Shanghai, China.  Co-may was moving toward the northwest at 9 m.p.h. (15 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 982 mb.

After meandering around Okinawa for several days Tropical Storm Co-may started to move toward the coast of eastern China south of Shanghai on Tuesday.  The distribution of thunderstorms in Tropical Storm Co-may was asymmetrical.  Thunderstorms were occurring in bands in the northern and western parts of Co-may’s circulation.  Bands in the eastern and southern parts of Tropical Storm Co-may consisted primarily of showers and lower clouds.

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

Tropical Storm Co-may will move through an environment somewhat favorable for intensification during then ext 12 hours.  Co-may will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the eastern side of an upper level trough that is over eastern Asia.  The upper level trough will produce southwesterly winds that will blow toward the top of Co-may’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification but the wind shear may not be enough to prevent intensification.  Tropical Storm Co-may could intensify during the next 12 hours.

Tropical Storm Co-may will move around the western end of a high pressure system over Japan.  The high pressure system will steer Co-may toward the northwest during the next 24 hours.  On its anticipated track, the center of Tropical Storm Co-may will be near Shanghai in less than 24 hours.

Tropical Storm Co-may will bring wind and rain to the region around Shanghai.  Heavy rain could cause floods in Zhejiang and Jiangsu.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Krosa was meandering south of Japan.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Krosa was located at latitude 28.6°N and longitude 142.9°E which put the center about 500 miles (805 km) south-southeast of Tokyo, Japan.  Krosa was moving toward the north at 2 m.p.h. (3 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 980 mb.

Iona Rapidly Intensifies to a Major Hurricane

Hurricane Iona rapidly intensified to a major hurricane over the Central Pacific Ocean south-southeast of Hawaii on Monday night.  At 5:00 a.m. EDT on Tuesday the center of Hurricane Iona was located at latitude 10.8°N and longitude 153.2°W which put the center about 790 miles (1270 km) south-southeast of Honolulu, Hawaii.  Iona was moving toward the west at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 964 mb.

Hurricane Iona continued to intensify rapidly during Monday night.  A small circular eye formed at the center of Iona’s circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Hurricane Iona.  Storms near the center of Iona generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease rapidly.

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

Hurricane Iona will move through an environment favorable for intensification during the next 24 hours.  Iona 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 Central Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Iona’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.  Hurricane Iona could continue to intensify during the next 24 hours.

Hurricane Iona will move around the southern side of a high pressure system over the Central Pacific Ocean.  The high pressure system will steer Iona toward the west during the next 24 hours.  On its anticipated track, Hurricane Iona will pass south of Hawaii on Tuesday.

Elsewhere over the Central Pacific Ocean, Tropical Storm Keli continue to move toward the west behind Hurricane Iona.  At 5:00 a.m. EDT on Tuesday the center of Tropical Storm Keli was located at latitude 12.5°N and longitude 146.6°W which put the center about 960 miles (1550 km) southeast of Honolulu, Hawaii.  Keli 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 1006 mb.

Iona Rapidly Intensifies to a Hurricane

Former Tropical Storm Iona rapidly intensified to a hurricane over the Central Pacific Ocean southeast of Hawaii on Monday.  At 11:00 a.m. EDT on Monday the center of Hurricane Iona was located at latitude 10.7°N and longitude 150.1°W which put the center about 895 miles (1440 km) southeast of Honolulu, Hawaii.  Iona was moving toward the west at 10 m.p.h. (16 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 994 mb.

Former Tropical Storm Iona rapidly intensified to a hurricane over the Central Pacific Ocean southeast of Hawaii on Monday.  The inner end of a rainband wrapped around the center of Hurricane Iona.  An eye appeared to be developing at the center of Iona’s circulation.  Bands of showers and thunderstorms were revolving around the center of Hurricane Iona.  Storms near the center of Iona generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

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

Hurricane Iona will move through an environment favorable for intensification during the next 24 hours.  Iona 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 Central Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Iona’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.  Hurricane Iona will intensify during the next 24 hours.

Hurricane Iona will move around the southern side of a high pressure system over the Central Pacific Ocean.  The high pressure system will steer Iona toward the west during the next 24 hours.  On its anticipated track, Hurricane Iona will pass south of Hawaii on Tuesday.

Elsewhere over the Central Pacific Ocean, Tropical Depression Two-C formed east-northeast of Hurricane Iona.  At 11:00 a.m. EDT on Monday the center of Tropical Depression Two-C was located at latitude 12.0°N and longitude 143.6°W which put the center about 1140 miles (1840 km) east-southeast of Honolulu, Hawaii.  Tropical Depression Two-C was moving toward the west at 13 m.p.h. (21 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.

Depression Strengthens to Tropical Storm Iona

Former Tropical Depression One-C strengthened to Tropical Storm Iona over the Central Pacific Ocean southeast of Hawaii on Sunday.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Iona was located at latitude 10.9°N and longitude 148.3°W which put the center about 965 miles (1545 km) southeast of Honolulu, Hawaii.  Iona was moving toward the west at 10 m.p.h. (16 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.

Former Tropical Depression One-C strengthened to Tropical Storm Iona over the Central Pacific Ocean southeast of Hawaii on Sunday.  More stronger thunderstorms formed near the center of Iona’s circulation.  Thunderstorms were also occurring in bands revolving around the center of Tropical Storm Iona.  Storms near the center of Iona started to generate upper level divergence that pumped mass away from the tropical storm.

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

Tropical Storm Iona will move through an environment favorable for intensification during the next 24 hours.  Iona 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 Central Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Iona’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 Iona will intensify during the next 24 hours.

Tropical Storm Iona will move around the southern side of a high pressure system over the Central Pacific Ocean.  The high pressure system will steer Iona toward the west during the next 24 hours.  On its anticipated track, Tropical Storm Iona will pass south of Hawaii on Tuesday.

Krosa Strengthens to a Typhoon

Former Tropical Storm Krosa strengthened to a typhoon over the Western North Pacific Ocean north of the Marianas on Sunday.  At 11:00 a.m. EDT on Sunday the center of Typhoon Krosa was located at latitude 23.3°N and longitude 145.4°E which put the center about 270 miles (435 km) north of Agrihan.  Krosa was moving toward the north-northeast at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 971 mb.

Former Tropical Storm Krosa strengthened to a typhoon north of the Marianas on Sunday.  The inner end of a rainband wrapped around the northern and western sides of the center of Typhoon Krosa.  Other bands of showers and thunderstorms were revolving around the center of Krosa’s circulation.  Storms near the center of Krosa generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The circulation around Typhoon Krosa became more symmetrical on Sunday.  Winds to typhoon force extended out 45 miles (75 km) from the center of Krosa’s circulation.  Winds to tropical storm force extended out 195 miles (315 km) from the center of Typhoon Krosa.

Tropical Storm Krosa will move through and environment somewhat favorable for intensification during the next 24 hours.  Krosa will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the eastern side of an upper level low centered southeast of Japan.  The upper level low will produce southerly winds that will blow toward the top of Krosa’s circulation.  Those winds will cause some vertical wind shear. The vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification. Typhoon Krosa could intensify during the next 24 hours.

Typhoon Krosa will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Krosa toward the north during the next 24 hours. On its anticipated track, the center of Typhoon Krosa will pass east of Iwo To.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Co-may strengthened back to a tropical storm near Okinawa.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Co-may was located at latitude 26.8°N and longitude 127.6°E which put the center about 15 miles (25 km) northeast of Okinawa.  Co-may was moving toward the west 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 986 mb.