Category Archives: Eastern and Central Pacific

TCs between Mexico and Hawaii

Tropical Storm Agatha Strengthens, Mexico Issues Hurricane Warning

Tropical Storm Agatha strengthened over the Eastern North Pacific Ocean on Saturday evening and the government of Mexico issued a Hurricane Warning for a portion of the coast. At 11:00 p.m. EDT on Saturday the center of Tropical Storm Agatha was located at latitude 13.9°N and longitude 98.7°W which put it about 190 miles (310 km) southwest of Puerto Angel, Mexico. Agatha was moving toward the northwest at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 998 mb.

A Hurricane Warning was in effect for the portion of the coast from Salina Cruz to Lagunas de Chacahua, Mexico. A Hurricane Watch was in effect for the portion of the coast from Salina Cruz to Barra de Tonala. Tropical Storm Warnings were in effect for the portions of the coast from Lagunas de Chacahua to Punta Maldonado and from Salina Cruz to Boca de Pijijiapan, Mexico.

Tropical Storm Agatha strengthened on Saturday. However, microwave satellite images suggested that the center of circulation in the middle troposphere could be a little to the northeast of the center at the surface. A ring of thunderstorms surrounded much of the center in the middle troposphere and the center at the surface could reform under the mid-tropospheric center. Thunderstorms around the center in the middle troposphere generated upper level divergence that pumped mass away from the tropical storm. Some drier air over Mexico appeared to get pulled into the northwestern part of Agatha’s circulation. Bands in the northwestern part of Tropical Storm Agatha consisted primarily of showers and lower clouds. Bands of thunderstorms were in the southern and eastern parts of Agatha. Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Storm Agatha.

Tropical Storm Agatha will move through an area favorable for intensification during the next 36 hours. Agatha will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the center of an upper level ridge over the Eastern North Pacific Ocean. The upper level winds are weak near the center of the ridge and there will be little vertical wind shear. Tropical Storm Agatha will intensify during the next 36 hours and it could strengthen to a hurricane on Sunday. Agatha could undergo a period of rapid intensification if the center at the surface reforms under the center in the middle troposphere and an inner core with an eye and an eyewall develop fully.

Tropical Storm Agatha will move around the western part of a high pressure system over Central America and the Eastern North Pacific Ocean. The high pressure system will steer Agatha toward the north during the next 12 hours. Agatha will move toward the northeast on Sunday night and Monday when it moves around the northwestern part of the high pressure system. On its anticipated track, Tropical Storm Agatha will move approach the coast of Mexico near Puerto Escondido and Puerto Angel on Monday afternoon. Tropical Storm Agatha is likely to be a hurricane when it approaches Mexico. There is a chance Agatha could be a major hurricane when it nears the coast of Mexico.

Tropical Depression One-E Strengthens to Tropical Storm Agatha, Mexico Issues Hurricane Watch

Former Tropical Depression One-E strengthened to Tropical Storm Agatha over the Eastern North Pacific Ocean south of Mexico on Saturday morning and the government of Mexico issued a Hurricane Watch for a portion of the coast. At 8:00 a.m. EDT on Saturday the center of Tropical Storm Agatha was located at latitude 13.1°N and longitude 98.4°W which put it about 220 miles (355 km) south-southwest of Puerto Angel, Mexico. Agatha was moving toward the west at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1002 mb.

The government of Mexico issued a Hurricane Watch for the portion of the coast from Punta Maldonado to Salina Cruz.

Tropical Storm Agatha strengthened on Saturday morning. More thunderstorms formed near the center of Agatha’s circulation. Microwave satellite images provided indications that a small eye was forming at the center of circulation. A partial ring of thunderstorms wrapped around the northern side of the center. Other bands of showers and thunderstorms were revolving around the center of Tropical Storm Agatha. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 35 miles (55 km) from the center of Agatha.

Tropical Storm Agatha will move through an area favorable for intensification during the next 36 hours. Agatha will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the western part of the axis of an upper level ridge over Central America and the Eastern North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear.. Tropical Storm Agatha will continue to intensify during the next 36 hours and it could strengthen to a hurricane on Sunday. Agatha could undergo a period of rapid intensification once an inner core with an eye and an eyewall are fully formed.

Tropical Storm Agatha will move around the western part of a high pressure system over Central America and the Eastern North Pacific Ocean. The high pressure system will steer Agatha toward the north during the next 36 hours. On its anticipated track, Tropical Storm Agatha will move closer to Mexico. Agatha could approach the coast of Mexico on Monday. Tropical Storm Agatha is likely to be a hurricane when it approaches Mexico. There is a chance Agatha could be a major hurricane when it nears the coast of Mexico.

Tropical Depression One-E Forms South of Mexico

Tropical Depression One-E formed over the Eastern North Pacific Ocean south of Mexico on Friday night. At 11:00 p.m. EDT on Friday the center of Tropical Depression One-E was located at latitude 12.8°N and longitude 97.9°W which put it about 220 miles (355 km) south-southwest of Puerto Angel, Mexico. Tropical Depression One-E was moving toward the west at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1006 mb.

More thunderstorms formed near the center of a low pressure system over the Eastern North Pacific Ocean south of Mexico on Friday night and the National Hurricane Center designated the system as Tropical Depression One-E. The inner end of a rainband wrapped around the northern and western sides of the center of Tropical Depression One-E. Other bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center began to generate upper level divergence that pumped mass away from the tropical depression.

Tropical Depression One-E will move through an area favorable for intensification during the next 48 hours. The depression will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the western part of the axis of an upper level ridge over Central America and the Eastern North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear.. Tropical Depression One-E will intensify to a tropical storm on Saturday and it could strengthen to a hurricane by the end of the weekend.

Tropical Depression One-E will move around the western part of a high pressure system over Central America and the Eastern North Pacific Ocean. The high pressure system will steer the tropical depression toward the north during the next 36 hours. On its anticipated track, Tropical Depression One-E will move closer to Mexico. The depression could approach the coast of Mexico on Monday. It could be a hurricane when it approaches Mexico. The government of Mexico is likely to issue watches and/or warnings for a portion of the coast on Saturday.

Tropical Depression Likely to Form South of Gulf of Tehuantepec

A tropical depression is likely to form over the Eastern North Pacific Ocean south of the Gulf of Tehuantepec. A broad area of low pressure was located south of the Gulf of Tehuantepec on Wednesday morning. At 8:00 a.m. EDT on Wednesday the center of the broad area of low pressure was located at latitude 12.0°N and longitude 96.0°W which put it about 270 miles (435 km) south of Puerto Angel, Mexico. The broad area of low pressure was moving toward the north at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1007 mb.

A broad area of low pressure over the Eastern North Pacific Ocean south of the Gulf of Tehuantepec was visible on early morning satellite images. Thunderstorms were forming in bands in the eastern and southern parts of the low pressure system. The thunderstorms were beginning to generate upper level divergence that was pumping mass away from the system. The strongest winds were occurring in the bands of thunderstorms.

The broad area of low pressure will be in an area favorable for the development of a tropical depression during the next several days. The low pressure system will move over water where the Sea Surface Temperatures are near 30˚C. It will be in an area where the upper level winds are weak and there will be little vertical wind shear.. The circulation around the low pressure system is likely to organize gradually and a tropical depression is likely to form later this week. After a tropical depression forms, it could move north toward Mexico and strengthen.

Possible Development East-Northeast of Hawaii

The National Hurricane Center (NHC) indicated that a low pressure system over the Eastern North Pacific Ocean east-northeast of Hawaii could develop into a subtropical or a tropical cyclone during the next 48 hours. The low pressure system is currently designated as Invest 90E. At 1:00 p.m. EST on Thursday the center of Invest 90E was located at latitude 21.8°N and longitude 136.1°W which put it about 1280 miles (2065 km) east-northeast of Hilo, Hawaii. It was moving toward the west-northwest 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 1006 mb.

The National Hurricane Center issued a Special Tropical Weather Outlook on Thursday afternoon which indicated that a low pressure system over the Eastern North Pacific Ocean had a 40% probability of development into a subtropical or a tropical cyclone during the next 48 hours. The low pressure system has been moving slowly toward the west between Baja California and Hawaii. The low pressure system currently has a hybrid structure. A well organized low level center of circulation was evident on visible satellite images. The low level center was located just to the east of a low pressure system in the middle and upper troposphere. The upper low was producing southerly winds that were blowing toward the top of the low level circulation. Those winds were causing moderate vertical wind shear and the wind shear was affecting the structure of the system. The strongest thunderstorms were occurring in bands north and east of the low level center of circulation. Bands south and west of the low level center consisted primarily of showers and lower clouds.

Invest 90E will move through an environment somewhat favorable for the formation of a subtropical or a tropical cyclone during the next 24 hours. The surface center of circulation will move over water where the Sea Surface Temperatures are near 24˚C. Since the upper low contains colder air, that water temperature is warm enough to support the development of a subtropical or a tropical cyclone. The low in the middle and upper troposphere will continue to cause moderate vertical wind shear. The wind shear will inhibit the development of a tropical cyclone. The current hybrid structure of Invest 90E and the marginally warm Sea Surface Temperatures would favor the development of a subtropical cyclone. However, if the strength of the upper level winds decreases, then a tropical cyclone could form.

Invest 90E will move south of a surface high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer the low level center of circulation toward the west-northwest during the next 24 hours. On its anticipated track Invest 90E will move slowly toward the Central Pacific Ocean.

Tropical Depression Terry Churns West

Tropical Depression Terry churned westward over the Eastern North Pacific Ocean on Wednesday. At 10:00 a.m. EST on Wednesday the center of Tropical Depression Terry was located at latitude 11.7°N and longitude 116.9°W which put it about 900 miles (1450 km) south-southwest of the southern tip of Baja California. Terry was moving toward the west at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1008 mb.

The distribution of thunderstorms around Tropical Depression Terry was asymmetrical. The strongest thunderstorms were occurring in bands in the southern half of Terry’s circulation. Bands in the northern half of the tropical depression consisted of showers and lower clouds. Sinking drier air was being pulled into the northern side of Tropical Depression Terry. The drier air was inhibiting the formation of thunderstorms in that part of the circulation. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical depression.

Tropical Depression Terry will move through an environment marginally favorable for intensification during the next 24 hours. Terry will move over water where the Sea Surface Temperatures are near 27˚C. It will move under the axis of an upper level ridge. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Drier air near the northern side of Terry’s circulation could continue to inhibit the develop of thunderstorms in that part of the tropical depression. Tropical Depression Terry is likely to maintain its intensity during the next 24 hours. Terry could strengthen if more thunderstorms develop near the center of circulation.

Tropical Depression Terry will move south of a surface high pressure system over the Eastern North Pacific Ocean during the next few days. The high pressure system will steer Terry toward the west. On its anticipated track Tropical Depression Terry will continue to move farther away from Mexico.

Tropical Storms Sandra and Terry Develop over East Pacific

Tropical Storms Sandra and Terry developed over the Eastern North Pacific Ocean on Sunday afternoon. At 4:00 p.m. EST on Sunday the center of Tropical Storm Sandra was located at latitude 14.0°N and longitude 115.2°W which put it about 705 miles (1135 km) south-southwest of the southern tip of Baja California. Sandra was moving toward the west-northwest 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 1006 mb.

At 4:00 p.m. EST on Sunday the center of Tropical Storm Terry was located at latitude 8.5°N and longitude 102.6°W which put it about 735 miles (1180 km) south of Manzanillo, Mexico. Terry was moving toward the west at 14 m.p.h. (22 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 1007 mb.

Based on data from a scatterometer on a satellite, the National Hurricane Center upgraded former Tropical Depression Nineteen-E to Tropical Storm Sandra on Sunday afternoon. It appeared from later satellite images that Tropical Storm Sandra might already be weakening. A large upper level trough approaching the west coast of the U.S. was producing strong southerly winds that were blowing across the top of Sandra’s circulation. Those winds were causing moderate vertical wind shear. The strong upper level winds blew the tops off thunderstorms near the center of Sandra. The strongest remaining thunderstorms were occurring in bands east of the center. Bands in other parts of Tropical Storm Sandra consisted primarily of showers and lower clouds. The strongest winds were in the eastern half of Sandra. Winds to tropical storm force extended out 90 miles in the eastern half of Sandra. The winds in the western half of the circulation were blowing at less than tropical storm force.

Tropical Storm Sandra will move through an environment mostly unfavorable for intensification during the next several days. Sandra will move over water where the Sea Surface Temperatures are near 27˚C. However, the large upper level trough will continue to produce strong vertical wind shear. The wind shear is likely to prevent Tropical Storm Sandra from strengthening. The strong shear could blow the top off of Sandra’s circulation and Tropical Storm Sandra is more likely to weaken during the next several days. Sandra will move south of a surface high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Sandra toward the west. On its anticipated track Tropical Storm Sandra will move farther away from Mexico.

More thunderstorms developed near the center of former Tropical Depression Eighteen-E on Sunday afternoon and the National Hurricane Center upgraded the system to Tropical Storm Terry. The circulation around Tropical Storm Terry exhibited more organization on satellite images. More thunderstorms also formed in bands revolving around the center of Terry. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 60 miles (95 km) on the eastern side of Terry’s circulation. The winds in the western half of Terry were blowing at less than tropical storm force.

Tropical Storm Terry will move through an environment somewhat favorable for intensification during the next 24 hours. Terry will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level wind are weak and there will be little vertical wind shear. Tropical Storm Terry could slowly intensify during the next 24 hours.

Tropical Storm Terry will move around the southern side of a surface high pressure system over the Eastern North Pacific Ocean. The high will steer Terry toward the west during the next few days. On its anticipated track Tropical Storm Terry will move farther away from Mexico.

Tropical Depression Forms South of El Salvador

Tropical Depression Eighteen-E formed over the Eastern North Pacific Ocean south of El Salvador in Thursday morning. At 11:00 a.m. EDT on Thursday the center of Tropical Depression Eighteen-E was located at latitude 9.4°N and longitude 90.0°W which put it about 300 miles (485 km) south of San Salvador, El Salvador. The tropical depression was moving toward the west at 8 m.p.h. (13 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 1007 mb.

Thunderstorms formed closer to the center of a small low pressure system south of El Salvador on Thursday morning and the National Hurricane Center designated the system as Tropical Depression Eighteen-E. The strongest thunderstorms were occurring in a band a little to the east of the center of circulation. Storms in that band began to generate upper level divergence that pumped mass away from the tropical depression. Bands in the western half of the depression consisted of showers and lower clouds.

Tropical Depression Eighteen-E will move through an environment somewhat favorable for intensification during the next 48 hours. The depression will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the northern part of an upper level ridge west of Central America. The northern part of the upper level ridge will produce weak westerly winds that will blow toward the top of the depression’s circulation. Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but it will not be strong enough to prevent the tropical depression from getting stronger. Tropical Depression Eighteen-E is likely to slowly intensify to a tropical storm during the next several days.

Tropical Depression Eighteen-E will move around the southern side of a surface high pressure system over the Eastern North Pacific Ocean. The high will steer the tropical depression toward the west during the next few days. On its anticipated track Tropical Depression Eighteen-E will move farther away from Central America.

Hurricane Rick Makes Landfall on West Coast of Mexico

Hurricane Rick made landfall on the west coast of Mexico on Monday morning. At 8:00 a.m. EDT on Monday the center of Hurricane Rick was located at latitude 18.2°N and longitude 102.1°W which put it about 15 miles (25 km) north-northeast of Lazaro Cardenas, Mexico. Rick was moving toward the north at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 977 mb.

A Hurricane Warning was in effect for the portion of the coast from Tecpan De Galeana to Punta San Telmo, Mexico. Tropical Storm Warnings were in effect for the portions of the coast from Punta San Telmo to Manzanillo and from Tecpan de Galeana to Acapulco, Mexico.

Hurricane Rick made landfall on the west coast of Mexico between Zihuatenajo and Lazaro Cardenas on Monday morning. Rick intensified before it made landfall. The maximum sustained wind speed increased to 105 m.p.h. (165 km/h) which made Rick a Category 2 hurricane on the Saffir-Simpson Scale. Even though Hurricane Rick intensified, the circulation remained relative small. Winds to hurricane force extended out 25 miles (40 km) from the center of Rick. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation.

The Hurricane Intensity Index (HII) for Hurricane Rick was 17.8. The Hurricane Size Index (HSI) was 8.2 and the Hurricane Wind Intensity Size Index (HWISI) was 26.0. Hurricane Rick was capable of causing regionalized serious damage.

Hurricane Rick was bringing strong winds and locally heavy rain to the portion of the coast between Lazaro Cardenas and Zihuatenajo. There were reports of damage in Ixtapa. Winds blowing water toward the coast were causing a storm surge. Heavy rain was falling over parts of Guerrero and Michoacan. The heavy rain could cause flash floods in some locations. Hurricane Rick will weaken steadily now that the center is inland. However, heavy rain will spread over inland sections of Guerrero and Michoacan and flash floods could occur in those areas.

Hurricane Rick Moves Toward Mexico

Hurricane Rick moved slowly toward the west coast of Mexico on Sunday afternoon. At 2:00 p.m. EDT on Sunday the center of Hurricane Rick was located at latitude 16.4°N and longitude 101.7°W which put it about 85 miles (135 km) south of Zihuatenajo, Mexico. Rick was moving toward the north at 6 m.p.h. (10 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 980 mb.

A Hurricane Warning was in effect for the portion of the coast from Tecpan De Galeana to Punta San Telmo, Mexico. Tropical Storm Warnings were in effect for the portions of the coast from Punta San Telmo to Manzanillo and from Tecpan de Galeana to Acapulco, Mexico.

The intensity of Hurricane Rick was steady during the past few hours. The inner core of Rick’s circulation was not as well organized as it was on Saturday afternoon. There were breaks in the ring of thunderstorms surrounding the center of Hurricane Rick. Storms near the center of circulation continued to generate upper level divergence that pumped mass away from the hurricane. Bands of showers and thunderstorms revolved around the center of Rick. The circulation around Hurricane Rick was small. Winds to hurricane force extended out 15 miles (25 km) from the center of Rick. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Hurricane Rick will move through an environment favorable for intensification during the next 12 hours. Rick will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Rick could intensify during the next 12 hours. However, the less organized core of Rick will limit intensification. An upper level trough near the west coast of the U.S. will produce strong southwesterly winds that will blow toward the top of Rick’s circulation on Monday. Those winds will cause vertical wind shear and the shear could cause Hurricane Rick to weaken as it nears the coast of Mexico.

Hurricane Rick will move around the western part of a high pressure system over Mexico during the next 24 hours. A large upper level trough near the west coast of the U.S. will cause the high pressure system to weaken. As the high pressure system weakens, the southern part of the upper level trough will steer Rick toward the north. On its anticipated track Hurricane Rick could make landfall on the west coast of Mexico on Sunday night. Hurricane Rick will bring strong winds and locally heavy rain to the portion of the coast near Zihuatanejo. Heavy rain could cause flash floods in parts of Guerrero and Michoacan on Sunday night and Monday.