Tag Archives: Tropical Storm Calvin

Tropical Storm Calvin Brings Gusty Winds and Rain to Hawaii

Tropical Storm Calvin brought gusty winds and rain to Hawaii on Wednesday. At 8:00 a.m. EDT on Wednesday the center of Tropical Storm Calvin was located at latitude 17.7°N and longitude 155.6°W which put it about 160 miles (260 km) south of Hilo, Hawaii. Calvin was moving toward the west at 20 m.p.h. (32 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.

A Tropical Storm Warning was in effect for Hawaii County.

After Tropical Storm Calvin strengthened late on Tuesday, it started to weaken again on Wednesday morning. An upper level trough northwest of Hawaii was producing southwesterly winds that were blowing toward the top of Calvin’s circulation. There were strong easterly winds in the lower levels of the atmosphere. The combination of southwesterly winds in the upper troposphere and easterly winds in the lower levels of the atmosphere caused strong vertical wind shear. The winds in the upper troposphere blew the top part of Tropical Storm Calvin toward the northeast. The strong easterly winds near the surface pushed the lower part of Calvin quickly toward the west.

The strong vertical wind shear caused Tropical Storm Calvin to weaken on Wednesday morning. The center of Calvin at the surface was passing south of the Big Island of Hawaii. Bands revolving around the center at the surface consisted primarily of showers and lower clouds. Thunderstorms were occurring in bands in the northern side of Tropical Storm Calvin where the wind was pushing air up the eastern slopes of the Hawaiian Islands. Winds to tropical storm force extended out 140 miles (220 km) in the northern side of Calvin’s circulation. Winds in the southern part of Calvin were blowing at less than tropical storm force.

Tropical Storm Calvin will move through an environment unfavorable for intensification during the next 24 hours. Calvin will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough northwest of Hawaii will continue to cause strong vertical wind shear. Tropical Storm Calvin will weaken to a tropical depression during the next 24 hours.

Tropical Storm Calvin will continue to produce gusty winds and locally heavy rain in Hawaii during the next 24 hours. The strongest wind gusts will occur at higher elevations. Calvin could cause isolated minor wind damage. Locally heavy rain could cause flooding in some locations. Flood Watches are in effect for the Big Island of Hawaii, Maui, Molokai, Lanai, and Kahoolawe.

Tropical Storm Calvin Speeds Toward Hawaii

Tropical Storm Calvin sped toward Hawaii on Tuesday. At 2:00 p.m. EDT on Tuesday the center of Tropical Storm Calvin was located at latitude 17.6°N and longitude 150.5°W which put it about 330 miles (640 km) east-southeast of Hilo, Hawaii. Calvin was moving toward the west at 22 m.p.h. (35 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 Tropical Storm Warning was in effect for Hawaii County.

Tropical Storm Calvin appeared to be getting stronger on Tuesday afternoon. More thunderstorms formed near the center of Calvin’s circulation. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Even though Tropical Storm Calvin appeared to be strengthening, the vertical structure of Calvin’s circulation seemed to tilt a little to the north in the middle and upper levels of the troposphere. Winds to tropical storm force extended out 105 miles (165 km) in the northern side of Tropical Storm Calvin. Winds to tropical storm force extended out 25 miles (40 km) in the southern side of Calvin.

Tropical Storm Calvin will move through an environment that will be somewhat favorable for intensification during the next 24 hours. Calvin will move over water where the Sea Surface Temperatures will increase to 26˚C. It will move through a region where the upper level winds are blowing from the south. Those winds are not very strong, but they will cause some vertical wind shear. Tropical Storm Calvin could strengthen during the next 24 hours in spite of the vertical wind shear.

Tropical Storm Calvin will move around the southern part of a subtropical high pressure system over the Eastern and Central Pacific Ocean. The high pressure system will steer Calvin toward the west during the next several days. On its anticipated track, Tropical Storm Calvin will move near the Big Island of Hawaii on Tuesday night. Calvin will bring gusty winds and locally heavy rain to Hawaii on Tuesday night and Wednesday. Flood Watches are in effect for the Big Island of Hawaii, Maui, Molokai, Lanai, and Kahoolawe.

Calvin Prompts Tropical Storm Watch for Hawaii

The potential impacts of Tropical Storm Calvin prompted the issuance of a Tropical Storm Watch for Hawaii. At 11:00 a.m. EDT on Monday the center of Tropical Storm Calvin was located at latitude 16.8°N and longitude 141.4°W which put it about 920 miles (1480 km) east of Hilo, Hawaii. Calvin was moving toward the west at 18 m.p.h. (30 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.

A Tropical Storm Watch was in effect for Hawaii County.

The U.S. Central Pacific Hurricane Center issued a Tropical Storm Watch for Hawaii County on Monday morning because of the potential effects of Tropical Storm Calvin. Former Hurricane Calvin weakened to a tropical storm on Sunday as it moved over cooler water east of Hawaii. Tropical Storm Calvin moved over water where the Sea Surface Temperatures were near 24˚C. Less energy was transported into the atmosphere from the cooler water and many of the thunderstorms in Calvin’s circulation dissipated. The bands revolving around the center of Tropical Storm Calvin consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 105 miles (165 km) in the northern side of Calvin’s circulation. Winds to tropical storm force extended out 60 miles (95 km) in the southern side of the circulation.

Tropical Storm Calvin will move through an environment that will be mostly unfavorable for intensification during the next 24 hours. Calvin will move over water where the Sea Surface Temperatures are near 25˚C. It will move through a region where then upper level winds that are weak and there will be little vertical wind shear. Tropical Storm Calvin could continue to weaken during the next 24 hours because of the cooler water even though there will be little vertical wind shear. Calvin will move over slightly warmer water when it gets closer to Hawaii.

Tropical Storm Calvin will move around the southern part of a subtropical high pressure system over the Eastern and Central Pacific Ocean. The high pressure system will steer Calvin toward the west during the next several days. On its anticipated track, Tropical Storm Calvin will move near Hawaii on Tuesday night. Calvin could still be a tropical storm when it approaches Hawaii. Tropical Storm Calvin will bring gusty winds and locally heavy rain to Hawaii on Tuesday night and Wednesday.

Tropical Storm Calvin Forms South of Baja California

Tropical Storm Calvin formed over the Eastern North Pacific Ocean south of Baja California on Wednesday morning. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Calvin was located at latitude 10.4°N and longitude 110.6°W which put it about 725 miles (1170 km) south of the southern tip of Baja California. Calvin 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. (105 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 morning and the U.S. National Hurricane Center designated the system as Tropical Storm Calvin. The distribution of thunderstorms in Tropical Storm Calvin was asymmetrical. Most thunderstorms were occurring in bands in the western side of Calvin’s circulation. Bands in the eastern side of Calvin consisted primarily of showers and lower clouds. The inner end of a rainband wrapped around the southern side of the center of Tropical Storm Calvin. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. The circulation around Calvin was small. Winds to tropical storm force extended out 45 miles (75 km) from the center of Calvin’s circulation.

Tropical Storm Calvin will move through an environment that will be mostly favorable for intensification during the next 36 hours. Calvin will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the southwestern part of an upper level ridge over Mexico and the southwestern U.S. The upper level ridge will produce easterly winds that will blow toward the top of Calvin’s circulation. Those winds will cause vertical wind shear. The wind shear will inhibit intensification, but the shear will not be enough to prevent Calvin from getting stronger. Tropical Storm Calvin will intensify during the next 36 hours. Calvin could strengthen to a hurricane by Friday.

Tropical Storm Calvin will move around the southern part of a subtropical high pressure system over the Eastern North Pacific Ocean. The high pressure system will Calvin toward the west during the next few days. On its anticipated track, Tropical Storm Calvin will move farther away from Mexico. Calvin could move over the Central Pacific Ocean early next week.

TD 03E Strengthens Into Tropical Storm Calvin

Tropical Depression 03E strengthened into Tropical Storm Calvin on Monday as it lingered south of Mexico.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Calvin was located at latitude 15.5°N and longitude 95.5°W which put it about 70 miles (110 km) east-southeast of Puerto Angel, Mexico.  Calvin was moving toward the west-northwest at 2 m.p.h. (3 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.  A Tropical Storm Warning remains in effect for the portion of the coast from Boca De Pijijiapan to Punta Maldonado.

A band of thunderstorms wrapped tightly around the southern side of the center of circulation of former Tropical Depression 03E and the National Hurricane Center upgraded the system to Tropical Storm Calvin in its 5:00 p.m. EDT advisory on Monday.  Calvin is a small tropical storm and winds to tropical storm force only extend out about 60 miles (95 km) from the center of circulation.  Additional bands of showers and thunderstorms are occurring in the outer portions of the circulation which are over the Pacific Ocean.

Tropical Storm Calvin is in an environment that is marginally favorable for intensification.  It is over water where the Sea Surface Temperature is near 30°C.  However, Calvin is also very near the coast of Mexico and it could start to pull drier air into the western part of the circulation at any time.  Calvin is under the eastern end of an upper level ridge which is producing northerly winds which are blowing toward the top of the tropical storm.  The northerly winds are producing moderate vertical wind shear and the shear may be contributing to the location of the main band thunderstorms south of the center of circulation.

The future intensity of Tropical Storm Calvin will depend on whether or not it remains over the Pacific Ocean.  If Calvin stays over the open water, then further intensification is possible.  If Calvin moves closer to the coast, then further intensification is much less likely.  If Calvin moves inland, it will dissipate quickly.

Tropical Storm Calvin is in an area where the steering currents are weak and it moved very slowly toward the west-northwest during the past 18 hours.  A subtropical ridge north of Calvin is forecast to begin to steer the tropical storm more quickly toward the west-northwest.  If that happens, Calvin could make landfall on the coast of Mexico near Puerto Angel in 12 to 24 hours.  Locally heavy rainfall remain the biggest risks with Tropical Storm Calvin.